liu.seSearch for publications in DiVA
Change search
Refine search result
12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 1.
    Alemon, B.
    et al.
    University of Guadalajara, Mexico .
    Flores, M.
    University of Guadalajara, Mexico .
    Canto, C.
    Instituto de Física, UNAM, Coyoacán, Mexico.
    Andrade, E.
    Instituto de Física, UNAM, Coyoacán, Mexico.
    de Lucio, O.G.
    Instituto de Física, UNAM, Coyoacán, Mexico.
    Rocha, M.F.
    ESIME-Z, Instituto Politécnico Nacional, Mexico.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Ion beam analysis, corrosion resistance and nanomechanical properties of TiAlCN/CNx multilayer grown by reactive magnetron sputtering2014In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, ISSN 0168-583X, E-ISSN 1872-9584, Vol. 331, p. 134-139Article in journal (Refereed)
    Abstract [en]

    A novel TiAlCN/CNx, multilayer coating, consisting of nine TiAlCN/CNx periods with a top layer 0.5 mu m of CNx, was designed to enhance the corrosion resistance of CoCrMo biomedical alloy. The multilayers were deposited by dc and RF reactive magnetron sputtering from Ti0.5Al0.5 and C targets respectively in a N-2/Ar plasma. The corrosion resistance and mechanical properties of the multilayer coatings were analyzed and compared to CoCrMo bulk alloy. Ion beam analysis (IBA) and X-ray diffraction tests were used to measure the element composition profiles and crystalline structure of the films. Corrosion resistance was evaluated by means of potentiodynamic polarization measurements using simulated body fluid (SBF) at typical body temperature and the nanomechanical properties of the multilayer evaluated by nanoindentation tests were analyzed and compared to CoCrMo bulk alloy. It was found that the multilayer hardness and the elastic recovery are higher than the substrate of CoCrMo. Furthermore the coated substrate shows a better general corrosion resistance than that of the CoCrMo alloy alone with no observation of pitting corrosion.

  • 2.
    Alemon, B.
    et al.
    University of Guadalajara, Mexico; Tecnol Monterrey, Mexico.
    Flores, M.
    University of Guadalajara, Mexico.
    Ramirez, W.
    University of Guadalajara, Mexico.
    Huegel, J. C.
    Tecnol Monterrey, Mexico.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Tribocorrosion behavior and ions release of CoCrMo alloy coated with a TiAlVCN/CNx multilayer in simulated body fluid plus bovine serum albumin2015In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 81, p. 159-168Article in journal (Refereed)
    Abstract [en]

    While the CoCrMo biomaterial is currently employed in artificial joints, there are medical concerns regarding its metal ion release and material loss caused by tribocorrosion. In this work, a TiAlVCN/CNx multilayer coating has been employed to improve the tribocorrosion-resistance of the CoCrMo substrate. During the tribocorrosion test, with the sample immersed in a simulated body fluid containing bovine serum albumin, open-circuit potential measurements showed more noble potential as well as a reduction of both the friction coefficient and wear-rate during the sliding phase. Inductive coupled plasma results demonstrate that the multilayer coating effectively blocked the emigration of metallic ions.

  • 3.
    Ali, Sharafat
    et al.
    Linnaeus University, Sweden; Corning Inc, NY 14831 USA.
    Paul, Biplab
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Roger
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Jonson, Bo
    Linnaeus University, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Birch, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Synthesis and characterization of the mechanical and optical properties of Ca-Si-O-N thin films deposited by RF magnetron sputtering2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 315, p. 88-94Article in journal (Refereed)
    Abstract [en]

    Ca-Si-O-N thin films were deposited on commercial soda-lime silicate float glass, silica wafers and sapphire substrates by RF magnetron co-sputtering from Ca and Si targets in an Ar/N-2/O-2 gas mixture. Chemical composition, surface morphology, hardness, reduced elastic modulus and optical properties of the films were investigated using X-ray photoelectron spectroscopy, scanning electron microscopy, nanoindentation, and spectroscopic ellipsometry. It was found that the composition of the films can be controlled by the Ca target power, predominantly, and by the reactive gas flow. Thin films in the Ca-Si-O-N system are composed of N and Ca contents up to 31 eq. % and 60 eq. %, respectively. The films thickness ranges from 600 to 3000 nm and increases with increasing Ca target power. The films surface roughness varied between 2 and 12 nm, and approximately decreases with increasing power of Ca target. The hardness (4-12 GPa) and reduced elastic modulus (65-145 GPa) of the films increase and decrease with the N and Ca contents respectively. The refractive index (1.56-1.82) is primarily dictated by the N content. The properties are compared with findings for bulk glasses in the Ca-Si-(Al)-O-N systems, and it is concluded that Ca-Si-O-N thin films have higher values of hardness, elastic modulus and refractive index than bulk glasses of similar composition. (C) 2017 Elsevier B.V. All rights reserved.

    The full text will be freely available from 2019-02-13 13:58
  • 4.
    Ali, Sharafat
    et al.
    Linnaeus University, Sweden.
    Paul, Biplab
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Roger
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Jonson, Bo
    Linnaeus University, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Birch, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Novel transparent Mg-Si-O-N thin films with high hardness and refractive index2016In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 131Article in journal (Refereed)
    Abstract [en]

    There is an increasing demand for glass materials with better mechanical and optical properties for display and electronic applications. This paper describes the deposition of novel thin films of Mg-circle divide-Si-O-N onto float glass substrates. Amorphous thin films in the Mg-Si-O-N system with high nitrogen and magnesium contents were deposited by reactive RF magnetron co-sputtering from Mg and Si targets in Ar/N-2/O-2 gas mixtures. The thin films studied span an unprecedented range of compositions up to 45 at% Mg and 80 at% N out of cations and anions respectively. Thin films in the Mg-Si-O-N system were found to be homogeneous and transparent in the visible region. Mechanical properties like hardness (H) and reduced elastic modulus (Er) show high values, up to 21 GPa and 166 GPa respectively. The refractive index (1.87-2.00) increases with increasing magnesium and nitrogen contents. (C) 2016 Elsevier Ltd. All rights reserved.

  • 5. Aouadi, S
    et al.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Stuber, M.
    Veprek, S.
    Franz, R.
    ICMCTF 2014 : Preface2014In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 572, p. 1-1Article in journal (Refereed)
    Abstract [en]

    The 41st International Conference on Metallurgical Coatings andThin Films (ICMCTF), sponsored by the Advanced Surface EngineeringDivision (ASED) of the American Vacuum Society (AVS), was heldfrom April 28 to May 2, 2014 in San Diego, California, USA.The week's technical program consisted of 37 technical sessions,which were organized into 13 symposia. The conference opened witha Plenary Lecture by Prof. Sybrand van der Zwaag, Materials Scienceand Engineering at the faculty of Aerospace Engineering at the TUDelft, The Netherlands, on “Self-healing Materials: an Alternative Approachto Create More Durable/Reliable Materials and Products”. TheExhibition Keynote Lecture was presented by Prof. Timothy P. Weihs,Department of Materials Science and Engineering at the Johns HopkinsUniversity, Baltimore, MD, USA, on “Driving Commercial Applicationsand Exploring Scientific Questions with Reactive Multilayer Foils”.During the conference week, a well subscribed poster session wasattended by a large and appreciative attendee audience. An expansivelarge two-day interactive industrial exhibition, with more than 50booths,was held inwhich companies displayed theirmost recent developmentsin vacuumscience and plasma-based deposition technologies.In addition to the technical symposia sessions, there were threefocused topical sessions, and six specialized short courses offered.Professor Jindrich Musil from the faculty of Applied Sciences atthe University of Bohemia, Plzeň, Czech Republic, was the recipientof the 2014 ASED R.F. Bunshah Annual Award; he presented the HonoraryLecture, “Advanced Hard Nanocomposite Coatings with UniqueProperties”. The award recognizes and honors Prof. Musil's seminalcontributions to the development of advanced nanocomposite coatingswith enhanced hardness, oxidation resistance, toughness, and crackresistance.The ASED Annual ICMCTF Graduate Student Awards werepresented to Shiyu Liu (Gold Medal), University of Cambridge, UK;Samantha K. Lawrence (Silver Medal), Purdue University, WestLafayette, IN, USA; and Trevor Hardcastle (Bronze Medal), Universityof Leeds, UK.The electronic submission and handling of manuscripts via theElsevier Editorial System (EES), including the selection of reviewersand evaluation ofmanuscripts,were identical to the procedures appliedto manuscripts submitted as regular contributions for publication ininternational scientific journals. Following the tradition practiced since1987, the accepted manuscripts are published in the archival journalsSurface and Coatings Technology and Thin Solid Films. ICMCTF 2014proceedings are open-access to the participants for one year via theElsevier journals' web sites.The organization of this conference and the preparation of proceedingsvolumes would have been impossible without the tremendouseffort and dedication of many individuals, including the General Chair,Yip-Wah Chung, Northwestern University, USA, and the ProgramChair, Claus Rebholz, the University of Cyprus, the team of symposiaand session chairs that made possible the realization of an exciting technicalprogram. We especially thank all the authors and presenters fortheir contributions; we also thank the hundreds of reviewers for theirtimely submission of high quality reports. To our sponsors,we acknowledge,appreciate, and thank these companies for their most generousand continuing support.The 42nd International Conference on Metallurgical Coatings andThin Films (ICMCTF 2015) will be held in San Diego, California, April20–24, 2015, with Claus Rebholz, University of Cyprus, as the GeneralChair and Suneel Kodambaka, the University of California at Los Angeles, as the Program Chair.

  • 6.
    Aouadi, Samir
    et al.
    University of North Texas, TX 76203 USA.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Figueroa, Carlos A.
    University of Caxias do Sul, Brazil.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Muratore, Christopher
    University of Dayton, OH 45469 USA.
    Stueber, Michael
    Karlsruhe Institute Technology, Germany.
    ICMCTF 2017-Preface2017In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 644Article in journal (Other academic)
    Abstract [en]

    n/a

  • 7.
    Bakoglidis, Konstantinos D.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Schmidt, Susann
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Nanotribological properties of wear resistant a-CNx thin films deposited by mid-frequency magnetron sputteringManuscript (preprint) (Other academic)
    Abstract [en]

    The nanotribological properties of amorphous carbon nitride (a-CNx) thin films deposited with mid-frequency magnetron sputtering (MFMS) were investigated at the nanoscale using an in-situ technique in a Hysitron Triboindenter TI 950. The friction coefficient, wear rate, track roughness, and the track profiles were recorded as a function of the number of linear reciprocal cycles, revealing the manner that the nanotribological and surface properties change during the wear test. The surface composition of  the films was evaluated by x-ray photoelectron spectroscopy (XPS). The friction coefficient ranges between 0.05 – 0.07, while the wear coefficient ranges from 9.4 x 10-8 up to 1.5 x 10-4 mm3/Nm. Debris particles and surface modifications characterize the friction and lubrication behavior in the track. The friction and main lubrication mechanism on the modified surface changes after the removal of debris particles, while this change appears at different cycle for each CNx film depending on the substrate bias voltage. Films grown at higher bias are modified earlier than films grown at lower bias. The wear behavior can be divided into two, track roughnessdependent, regimes; (1) films with track roughness > 1 nm showed wear with obvious tracks and (2) the films with roughness < 1 nm showed negative wear at the nanometer scale with a volume of material projected in the area of the wear track. This material volume is believed to be result of a surface modification, where the molar volume of the modified surface is larger than the molar volume of the surface before the wear test.

  • 8.
    Bakoglidis, Konstantinos
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Glenat, Herve
    Technosud, France.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Schmidt, Susann
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Grillo, Stefano
    Technosud, France; University of Perpignan, France.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Comparative study of macro- and microtribological properties of carbon nitride thin films deposited by HiPIMS2017In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 370Article in journal (Refereed)
    Abstract [en]

    The macro- and microtribological properties of carbon nitride thin films deposited by high power impulse magnetron sputtering at different substrate bias voltages (V-b) were investigated. V-b of -100, -150, -200, and-300 V were used. A Hysitron Triboindenter TI950 and a reciprocating Tribotechnic tribometer with diamond counterparts were used in order to assess the tribological performance of the films at the micro- and macroscale, respectively. Initial Hertzian contact pressures of 2.5 GPa, 3.3 GPa and 3.9 GPa were chosen for the comparative measurements at both scales. At the macroscale, films with higher initial roughness present an increased wear. Debris creation and asperity deformation takes place causing abrasive wear. At the microscale, compression of the surface material occurs. The run-in friction shows similar trends at both scales; an initial decrease and an increase thereafter. Steady-state friction is not reached at the microscale, attributed to the absence of a graphitic tribolayer in the contact. At the macroscale, all films show abrasive wear and debris creation. Here, the changes in friction coefficients are attributed to the debris loss from the contact during the tribotests. The CN film tested at 2.5 GPa shows a continuous increase of friction, due to the continuous loss of debris from the contact. The other films reach a steady-state friction coefficient, since most of the debris is lost before the end of the tribotests. (C) 2016 Elsevier B.V. All rights reserved.

  • 9.
    Bofelli, Daniel
    et al.
    University of Buenos Aires, Argentina.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology. University of Buenos Aires, Argentina.
    Zimmerman, Rosa
    University of Buenos Aires, Argentina.
    Electrical and Piezoresistive Properties of Thick Film Resistors (Propiedades Eléctricas y Piezorresistivas de Resistores de Película Gruesa)1997In: Anales AFA, ISSN 1850-1158, Vol. 8, no 1, p. 198-200Article in journal (Refereed)
    Abstract [en]

    Thick film cermet resistors, adjusted by conventional trimming methods, undergo irreversible changes in successive deformation cycles. In this work the stability of resistors adjusted by laser irradiation is evaluated. Resistance, thermal coefficient of resistance, and strain gauge factor in resistors with and without surface treatment are studied. The irradiated surface was characterized by Auger spectroscopy.

  • 10.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    A new method for in-situ measurement of nano-friction and nano-wear of thin films by using the Triboindenter TI-9502014In: Nanobrucken 2014, Saarbrucken, Germany: INM - Leibniz Institute for New Materials , 2014, p. 24-Conference paper (Other academic)
    Abstract [en]

    The Triboindenter present many advantages for the measurement of friction and wear at the nanoscale. A reciprocating multi-cycle linear test can be programmed, from where it is possible to obtain simultaneously the friction force and wear rate from the lateral force and vertical displacement sensors, respectively. The friction values have high precision but the wear data is usually wrong in long duration tests because the drift rate is only measured just before the test start. Alternatively, one can program the SPM scanning mode of the instrument with a high load in order to produce the wear of the surface. At the end of the experiment, a squared hole is produced which can be measured using the SPM facility of the system. However, this wear experiment does not allow the simultaneous measurement of the friction coefficient.In this talk I will present a new methodology to measure in-situ the friction and wear of thin films using a Triboindenter TI-950 from Hysitron. I will show how the possible changes of drift rate during long-time tests can be overcome, obtaining simultaneous precise values of friction and wear rate as a function of time. I will discuss how the Triboimage® software can be adapted to this methodology in order to get realistic values of friction and wear. Finally I will show some results for soft (H < 1GPa) Pb films and very hard (H ~ 35 GPa) nitride coatings

  • 11.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Advances in science and technology of polymers and composite materials2018In: E-Polymers, ISSN 1618-7229, E-ISSN 1618-7229, Vol. 18, no 1Article in journal (Other academic)
    Abstract [en]

    n/a

  • 12.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Editorial Material: INTRODUCTION in POLYMERS and POLYMER COMPOSITES, vol 22, issue 8, pp2014In: Polymers & polymer composites, ISSN 0967-3911, E-ISSN 1478-2391, Vol. 22, no 8Article in journal (Other academic)
    Abstract [en]

    n/a

  • 13.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Editorial Material: Novel insights in polymer and composite materials in E-POLYMERS, vol 15, issue 5, pp 285-2862015In: E-Polymers, ISSN 1618-7229, E-ISSN 1618-7229, Vol. 15, no 5, p. 285-286Article in journal (Other academic)
    Abstract [en]

    n/a

  • 14.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Indentation Hardness Measurements at Macro-, Micro-, and Nanoscale: A Critical Overview2017In: Tribology letters, ISSN 1023-8883, E-ISSN 1573-2711, Vol. 65, no 1Article, review/survey (Refereed)
    Abstract [en]

    The Brinell, Vickers, Meyer, Rockwell, Shore, IHRD, Knoop, Buchholz, and nanoindentation methods used to measure the indentation hardness of materials at different scales are compared, and main issues and misconceptions in the understanding of these methods are comprehensively reviewed and discussed. Basic equations and parameters employed to calculate hardness are clearly explained, and the different international standards for each method are summarized. The limits for each scale are explored, and the different forms to calculate hardness in each method are compared and established. The influence of elasticity and plasticity of the material in each measurement method is reviewed, and the impact of the surface deformation around the indenter on hardness values is examined. The difficulties for practical conversions of hardness values measured by different methods are explained. Finally, main issues in the hardness interpretation at different scales are carefully discussed, like the influence of grain size in polycrystalline materials, indentation size effects at micro-and nanoscale, and the effect of the substrate when calculating thin films hardness. The paper improves the understanding of what hardness means and what hardness measurements imply at different scales.

  • 15.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Innovations in polymers and composite materials2017In: E-Polymers, ISSN 1618-7229, E-ISSN 1618-7229, Vol. 17, no 1Article in journal (Other academic)
    Abstract [en]

    n/a

  • 16.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Preface in POLYMERS and POLYMER COMPOSITES2017In: Polymers & polymer composites, ISSN 0967-3911, E-ISSN 1478-2391, Vol. 25, no 1Article in journal (Other academic)
    Abstract [en]

    n/a

  • 17.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    The nature of the frictional force at the macro-, micro-, and nano-scales2014In: Friction, E-ISSN 2223-7690, Vol. 2, no 1, p. 40-46Article in journal (Refereed)
    Abstract [en]

    Nowadays it is accepted that the friction force is a combined effect arising from various phenomena: adhesive forces, capillary forces, contact elasticity, topography, surface chemistry, and generation of a third body, etc. Any of them can dominate depending on the experimental force and length scales of the study. Typical forces in macro-tribology are in the Newtons, while are reduced to milli-/micro-Newtons, and nano-Newtons in micro- and nano-tribology, respectively. In this paper, experimental friction results from fullerene like CN x films and single-crystal Si at the three scales will be discussed. The complex and broad variety of processes and phenomena connected with the dry friction coefficient at the macro-, micro-, and nano-scale point of view will be highlighted.

  • 18.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Becker, Richard
    Studsvik Nuclear AB.
    Dozaki, Koji
    The Japan Atomic Power Company.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    A Novel Oxide Characterization Method of Nickel Base Alloy 600 Used in Nuclear Plant Reactors2013In: / [ed] F. Marquis, Hoboken, NJ, USA: John Wiley & Sons, 2013, p. 415-Conference paper (Refereed)
    Abstract [en]

    The Alloy 600 is a polycrystalline nickel base alloy used in pressurized water reactors (PWR) of nuclear power plants. Long term exposure of the alloy to primary water of PWR generates an oxide film that strongly influences the stress corrosion cracking behavior of the alloy. Recently, it has been shown that the oxide film structure, composition and thickness depend on the dissolved hydrogen content in the primary water. In this work we have explored a novel approach which enables a high spatial resolution oxide thickness measurement by nanomechanical testing. Oxide films have been grown on Alloy 600 specimens exposed between 5000 and 35000 hours at 320-330°C with hydrogen levels in the range 5 to 25 mL H2/kg H2O. A Triboindenter TI-950 from Hysitron was used to measure the change of nanomechanical properties in polished cross-sections. The increase of hardness has been correlated to the presence of oxides.

  • 19.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Bojorge, C
    CINSO, Argentina.
    Elhordoy, F
    Instituto de Física & CINQUIFIMA, Uruguay.
    Kent, V.
    Instituto de Física & CINQUIFIMA, Uruguay.
    Zanini Gadioli, G
    Instituto de Física Gleb Wataghin, Brazil.
    Marotti, R.
    Instituto de Física & CINQUIFIMA, Uruguay.
    Canepa, H
    CINSO, Argentina.
    Dalchiele, E. A.
    Instituto de Física & CINQUIFIMA, Uruguay.
    Comparative study on the properties of ZnO nanowires and nanocrystalline thin films2012In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 213, p. 59-64Article in journal (Refereed)
    Abstract [en]

    The microstructural, morphological, optical and water-adsorption properties of nanocrystalline ZnO thin films and ZnO nanowires were studied and compared. The ZnO thin films were obtained by a sol–gel process, while the ZnO nanowires were electrochemically grown onto a ZnO sol–gel spin-coated seed layer. Thin films and nanowire samples were deposited onto crystalline quartz substrates covered by an Au electrode, able to be used in a quartz crystal microbalance. X-ray diffraction measurements reveal in both cases a typical diffraction pattern of ZnO wurtzite structure. Scanning electron microscopic images of nanowire samples show the presence of nanowires with hexagonal sections, with diameters ranging from 30 to 90 nm. Optical characterization reveals a bandgap energy of 3.29 eV for the nanowires and 3.35 eV for the thin films. A quartz crystal microbalance placed in a vacuum chamber was used to quantify the amount and kinetics of water adsorption onto the samples. Nanowire samples, which have higher surface areas than the thin films, adsorb significantly more water.

  • 20.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Czigany, Zs.
    Res Inst Tech Phys and Mat Sci,Budapest.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Bohlmark, J.
    Sandvik Tooling RandD.
    Cremer, R.
    CemeCon AG.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Industrial-scale deposition of highly adherent CNx films on steel substrates2010In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 204, no 21-22, p. 3349-3357Article in journal (Refereed)
    Abstract [en]

    Highly adherent carbon nitride (CNx) films were deposited using a novel pretreatment with two high power impulse magnetron sputtering (HIPIMS) power supplies in a master-slave configuration: one to establish the discharge and one to produce a pulsed substrate bias. During the pretreatment, SKF3 (AISI 52100) steel substrates were pulse-biased in the environment of a HIPIMS Cr plasma in order to sputter clean the surface and to implant Cr metal ions. Subsequently. CNx films were prepared at room temperature by DC unbalanced magnetron sputtering from a high purity graphite target in a N-2/Ar discharge at 3 mTorr. All processing was done in an industrial CemeCon CC800 system. A series of depositions were obtained with samples at different bias voltages (DC and pulsed) in the range of 0-800 V. Scanning transmission microscopy (STEM) and high resolution transmission electron microscopy (HRTEM) show the formation of an interface comprising a polycrystalline Cr layer of 100 nm and an amorphous transition layer of 5 nm. The adhesion of CNx films evaluated by the Daimler-Benz Rockwell-C reach strength quality HF1, and the scratch tests gives critical loads of 84 N. Adhesion results are correlated to the formation of an optimal interfacial mixing layer of Cr and steel.

  • 21.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Flores-Ruiz, Francisco
    Centro de Investigacion y de Estudios Avanzados del I.P.N., Unidad Queretaro.
    Novel method for in-situ and simultaneous nanofriction and nanowear characterization of materials2015In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 34, article id 043201Article in journal (Refereed)
    Abstract [en]

    Nowadays, there is an increased need to know the nanotribological properties of protectivecoatings used in part devices operating under nano- and microcontact situations, e.g., hard diskdrives, magnetic heads, microelectromechanical systems and microsensors, etc. Therefore, there isa demand for instruments and methods testing friction and wear at the nano- and microscales. Inthis work, the authors present a new methodology to measure simultaneously the friction, and wearof a surface. The authors have designed an experiment, where a probe is permanently scanning a10 lm track in a reciprocal movement. Different loads are applied in order to obtain thetopographic information which is used to calculate the wear rate and roughness evolution. Forcelateral sensors register simultaneously the friction force variations. The experimental input data areinformation vectors that contain: load (lN), friction force (lN), vertical Z displacement (nm),lateral X displacement (nm), and time (s). The data are processed using a simple program runningin MathLabVR which eliminates the thermal drift. The software output gives the resulting frictioncoefficient, track roughness, and wear rate as a function of the running cycles of the probe. Thenew method builds a novel bridge to relate tribological mechanisms at different scales

  • 22.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Flores-Ruiz, Francisco J.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. IPN, Mexico.
    Di Giulio, Massimo
    University of Salento, Italy.
    Gontad, Francisco
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Lorusso, Antonella
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Perrone, Alessio
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Microstructural, nanomechanical, and microtribological properties of Pb thin films prepared by pulsed laser deposition and thermal evaporation techniques2016In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 34, no 2, p. 021505-Article in journal (Refereed)
    Abstract [en]

    In this work, the authors compare the morphological, structural, nanomechanical, and microtribological properties of Pb films deposited by thermal evaporation (TE) and pulsed laser deposition (PLD) techniques onto Si (111) substrates. Films were investigated by scanning electron microscopy, surface probe microscopy, and x-ray diffraction in theta-2 theta geometry to determine their morphology, root-mean-square (RMS) roughness, and microstructure, respectively. TE films showed a percolated morphology with densely packed fibrous grains while PLD films had a granular morphology with a columnar and tightly packed structure in accordance with the zone growth model of Thornton. Moreover, PLD films presented a more polycrystalline structure with respect to TE films, with RMS roughness of 14 and 10 nm, respectively. Hardness and elastic modulus vary from 2.1 to 0.8 GPa and from 14 to 10 GPa for PLD and TE films, respectively. A reciprocal friction test has shown that PLD films have lower friction coefficient and wear rate than TE films. Our study has demonstrated for first time that, at the microscale, Pb films do not show the same simple lubricious properties measured at the macroscale. (C) 2015 American Vacuum Society.

  • 23.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Furlan, Andrej
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Geuorguiev, G. K.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Czigany, Zsolt
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Högberg, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Structural and Mechanical Properties of CNx and CPx Thin Solid Films2012In: Key Engineering Materials, ISSN 1013-9826, E-ISSN 1662-9795, Vol. 488-489, p. 581-584Article in journal (Refereed)
    Abstract [en]

    The inherent resiliency, hardness and relatively low friction coefficient of the fullerene-like (FL) allotrope of carbon nitride (CNx) thin solid films give them potential in numerous tribological applications. In this work, we study the substitution of N with P to grow FL-CPx to achieve better cross- and inter-linking of the graphene planes, improving thus the materials mechanical and tribological properties. The CNx and CPx films have been synthesized by DC magnetron sputtering. HRTEM have shown the CPx films exhibit a short range ordered structure with FL characteristics for substrate temperature of 300 degrees C and for a phosphorus content of 10-15 at.%. These films show better mechanical properties in terms of hardness and resiliency compared to those of the FL-CNx films. The low water adsorption of the films is correlated to the theoretical prediction for low density of dangling bonds in both, CNx and CPx. First-principles calculations based on Density Functional Theory (DFT) were performed to provide additional insight on the structure and bonding in CNx, CPx and a-C compounds.

  • 24.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Adhesion improvement of carbon-based coatings through a high ionization deposition technique2012In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 370, no 012009Article in journal (Refereed)
    Abstract [en]

    The deposition of highly adherent carbon nitride (CNx) films using a pretreatment with two high power impulse magnetron sputtering (HIPIMS) power supplies in a master-slave configuration is reviewed. SKF3 (AISI 52100) steel substrates were pretreated in the environment of a high ionized Cr+Ar plasma in order to sputter clean the surface and implant Cr metal ions. CNx films were subsequently deposited at room temperature by DC magnetron sputtering from a high purity C target in a N-2/Ar plasma discharge. All processing was done in an industrial-scale CemeCon CC800 coating system. A series of depositions were obtained with samples pretreated at different bias voltages (DC and pulsed). The adhesion of CNx films, evaluated by the Daimler-Benz Rockwell-C test, reaches strength quality HF1. Adhesion results are correlated to high resolution transmission electron microscopy observations confirming the formation of an optimal interfacial mixing layer of Cr and steel. The throwing power increase for HIPIMS coatings is associated to the higher ionization in the plasma discharge.

  • 25.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Advanced Carbon-Based Coatings2014In: Comprehensive Materials Processing, Elsevier, 2014, 4, p. 389-412Chapter in book (Refereed)
    Abstract [en]

    This chapter focuses on the development of alloyed diamondlike coatings, in particular a new class of fullerene-like (FL) materials. We describe unique resilient FL compounds by self-organization of nano-curved sp2-hybridized carbon features, with tuned mechanical and surface energy properties. These unique resilient materials consist of bent and intersecting hexagonal basal planes, fabricated by the incorporation of odd-member rings. Cross-linking enables the material to extend the strength of the covalently 2D hexagonal graphene network into 3D. The microstructural properties of three types of coatings, which have the possibility to be applied on a large scale, are described: carbon nitride, phosphorous carbide, and carbon fluoride.

  • 26.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Beschichtungsverfahren und Vorrichtung zum Beschichten2009Patent (Other (popular science, discussion, etc.))
  • 27.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Tribology of Carbon-Based Coatings: Past, Present, and Future2013In: Proceeding of the 2nd International Workshop of Tribology Tribaries 2013, 2013, p. 7-10Conference paper (Other academic)
    Abstract [en]

    In this talk, the development of carbon-based coatings will be reviewed. The most recent findings in the synthesis, characterization and application of carbon-based coatings will be highlighted. Future perspectives of new fullerene-like carbon-based tribological coatings will be discussed. Novel applications of fullerene-like CNx, CPx, and CFx will be envisioned.

  • 28.
    Broitman, Esteban
    et al.
    Departamento Fisica, Facultad de Ingenieria, Universidad de Buenos Aries, Buenos Aries, Argentina.
    Latorre, D.
    Departamento Fisica, Facultad de Ingenieria, Universidad de Buenos Aries, Buenos Aries, Argentina.
    Zimmeman, Rosa
    Departamento Fisica, Facultad de Ingenieria, Universidad de Buenos Aries, Buenos Aries, Argentina.
    Resistividad Eléctrica de Películas Delgadas de Oro Obtenidas por Ion-Plating [Electrical Resistivity of Au Thin Films Deposited by Ion-Plating]1992In: Anales AFA, ISSN 1850-1158, Vol. 3, no 1, p. 357-360Article in journal (Refereed)
    Abstract [en]

    Es sabido que la resistividad eléctrica de las películas delgadas es mayor que la del material en volumen aún para espesores para los cuales el efecto Fuchs-Sondheimer es despreciable. En este caso, la mayor contribución a la resistividad se debe a impurezas y defectos cristalinos. Por eso es interesante hacer mediciones eléctricas en películas en que se pueda establecer la variación de la resistividad con la concentración de defectos, en especial bordes de grano. Esto puede lograrse comparando películas depositadas en vacío y por ion-plating porque esta última produce películas con tamaño de grano significativamente menor que las evaporadas en vacío. En este trabajo se presentan mediciones de la resistividad de películas continuas de oro obtenidas por ambas técnicas, antes y después de tratamientos técnicos. El tamaño de grano de las películas fue observado por microscopía electrónica. Se discuten los resultados en función de la contribución a la resistividad del scattering en los bordes de grano.

  • 29.
    Broitman, Esteban
    et al.
    University of Buenos Aires, Argentina.
    Latorre, Daniel
    University of Buenos Aires, Argentina.
    Sendra, Claudia
    University of Buenos Aires.
    Zimmerman, Rosa
    University of Buenos Aires.
    Thin Film Humidity Sensors (Sensores de Humedad de Película Delgada)1991In: Anales AFA, ISSN 1850-1158, Vol. 2, no 1, p. 277-279Article in journal (Refereed)
    Abstract [en]

    In this paper the construction and characterization of a humidity sensor with an alumina thin film responsive element is described. The capacitive sensor, made by thin film technology, consists of a dielectric layer of Al2O3 film deposited between metal electrodes.

  • 30.
    Broitman, Esteban
    et al.
    University of Buenos Aires, Argentina.
    Latorre, Daniel
    University of Buenos Aires, Argentina.
    Zimmerman, Rosa
    University of Buenos Aires, Argentina.
    Thin Film Temperature Sensors (Sensores de Temperatura de Película Delgada)1990In: Anales AFA, ISSN 1850-1158, Vol. 1, no 1, p. 336-338Article in journal (Refereed)
    Abstract [en]

    Ni thin films of 1800 Å thick were deposited by ion-plating and designed by photolithography to be used as temperature sensors. The resistive paths were finished with contact Cu welding terminals. After being coated with a protective layer of SiOx, they were subjected to heat stabilization treatments. Small, stable and accurate sensors were obtained.

  • 31.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Nedelcu, Dumitru
    Gheorghe Asachi Tech Univ Iasi, Romania.
    Special Issue on: Modern Technologies as Future Solutions for Performance Products Introduction2018In: International journal of materials & product technology, ISSN 0268-1900, E-ISSN 1741-5209, Vol. 56, no 1-2Article in journal (Other academic)
    Abstract [en]

    n/a

  • 32.
    Broitman, Esteban
    et al.
    Carnegie Mellon University, Pittsburgh, PA, USA .
    Neihardt, Jörg
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Fullerene-like Carbon Nitride: A New Carbon-based Tribological Coating2008In: Tribology of Diamond-Like Carbon Films: Fundamentals and Applications, Springer, 2008, 1, p. 620-653Chapter in book (Refereed)
    Abstract [en]

    In 1994, researchers at Linköping University discovered the fullerene-like allotrope of carbon nitride (FL-CNx) by using reactive magnetron sputtering in a nitrogen-containing atmosphere at rather low ion energy assistance. FL-CNx is a predominantly sp2-hybridized material with nitrogen structurally incorporated either substitutionally in a graphite sheet or in a pyridine-like manner, which initiates bending by formation of pentagons and cross-linking, respectively. The assumed nitrogen-induced cross-linkage between the sheets contributes considerably to the strength of FL-CNx by preventing interplanar slip. This results in an extremely fracture tough, elastic, and compliant material, which deforms by reversible bond rotation and bond angle deflection rather than slip and bond breaking.

  • 33.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Tengdelius, Lina
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Hangen, Ude D.
    Hysitron Inc., Minneapolis, Minnesota, USA.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Högberg, Hans
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    High-temperature nanoindentation of epitaxial ZrB2 thin films2016In: Scripta Materialia, ISSN 1359-6462, E-ISSN 1872-8456, Vol. 124, p. 117-120Article in journal (Refereed)
    Abstract [en]

    We use in-situ heated nanoindentation to investigate the high-temperature nanomechanical properties of epitaxial and textured ZrB2 films deposited by magnetron sputtering. Epitaxial films deposited on 4H-SiC(0001) show a hardness decrease from 47 GPa at room temperature to 33 GPa at 600 °C, while the reduced elastic modulus does not change significantly. High resolution electron microscopy (HRTEM) with selected area electron diffraction of the indented area in a 0001-textured film reveals a retained continuous ZrB2 film and no sign of crystalline phase transformation, despite massive deformation of the Si substrate. HRTEM analysis supports the high elastic recovery of 96% in the films.

    The full text will be freely available from 2018-07-13 14:36
  • 34.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Yousuf Soomro, Muhammad
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Nanoscale piezoelectric response of ZnO nanowires measured using a nanoindentation technique2013In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 15, no 26, p. 11113-11118Article in journal (Refereed)
    Abstract [en]

    We report the piezoelectric properties of ZnO nanowires (NWs) obtained by using a nanoindenter with a conductive boron-doped diamond tip. The direct piezoelectric effect was measured by performing nanoindentations under load control, and the generated piezoelectric voltage was characterized as a function of the applied loads in the range 0.2-6 mN. The converse piezoelectric effect was measured by applying a DC voltage to the sample while there was a low applied force to allow the tip being always in physical contact with the NWs. Vertically aligned ZnO NWs were grown on inexpensive, flexible, and disposable paper substrates using a template-free low temperature aqueous chemical growth method. When using the nanoindenter to measure the direct piezoelectric effect, piezopotential values of up to 26 mV were generated. Corresponding measurement of the converse piezoelectric effect gave an effective piezoelectric coefficient d(33)(eff) of similar to 9.2 pm V-1. The ZnO NWs were also characterized using scanning electron microscopy, X-ray diffraction, and high-resolution transmission electron microscopy. The new nanoindentation approach provides a straightforward method to characterize piezoelectric material deposited on flexible and disposable substrates for the next generation of nanodevices.

  • 35.
    Broitman, Esteban
    et al.
    University of Buenos Aires, Argentina .
    Zimmerman, Rosa
    University of Buenos Aires, Argentina .
    Influence of deposition parameters on the microstructure of ion-plated films1996In: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 378, p. 356-359Article in journal (Refereed)
    Abstract [en]

    Ion plating is essentially vapor deposition onto a substrate which is the cathode of a glow discharge. The most important characteristic of the technique is that the growing film is subjected to a flux of high energy particles (neutrals and ions). In this study we report information about the effect of ion plating parameters on grain diameter and crystallite size distribution. At a constant potential grain size remains constant with the increase of ion density. On the other hand, at a constant ion density the grain size decreases with the substrate potential increment. Ion bombardment also has an effect on the crystallite size distribution. The ion plated films show a higher degree of uniformity in grain size than vacuum evaporated films. In contrast with vacuum evaporated films, where the grain size is proportional to the thickness, no variation of grain size with film thickness has been observed for the ion‐plated films. Electron diffraction patterns have shown that the orientation remains near random over the entire J and V range studied.

  • 36.
    Broitman, Esteban
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology. Laboratorio de Peliculas Delgudas, Facultad de Ingenieria, Universidad de Buenos Aires, Buenos Aires, Argentilta.
    Zimmerman, Rosa
    Laboratorio de Peliculas Delgudas, Facultad de Ingenieria, Universidad de Buenos Aires, Buenos Aires, Argentilta.
    Resistividad Eléctrica Residual en Péliculas Delgadas [Residual Electrical Resistivity in Thin Metal Films]1994In: Anales AFA, ISSN 1850-1158, Vol. 5, no 1, p. 280-282Article in journal (Refereed)
    Abstract [es]

    Ha sido bien establecido que la resistividad de las películas, delgadas depende fuertemente de su estructura. Para entender mejor dicha influencia se comparó la resistividad residual (0°K) de películas obtenidas por evaporación en vacío y por ion-plating. Las películas obtenidas por esta última técnica se caracterizan por tener un diámetro de grano menor y mayor uniformidad en tamaño y forma de los granos. La resistividad residual fue determinada midiendo la resistividad a distintas temperaturas para muestras de distintos espesores. El tamaño de grano se obtuvo por microscopía electrónica de transmisión.

  • 37.
    De Bona, J.
    et al.
    INTEMA Institute of Materials Science and Technology, University of Mar del Plata, Argentina.
    Laino, S.
    INTEMA Institute of Materials Science and Technology, University of Mar del Plata, Argentina.
    Pettarin, V.
    INTEMA Institute of Materials Science and Technology, University of Mar del Plata, Argentina.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Dommarco, R.
    INTEMA Institute of Materials Science and Technology, University of Mar del Plata, Argentina.
    Frontini, P.
    INTEMA Institute of Materials Science and Technology, University of Mar del Plata, Argentina.
    Differences in the Sliding Wear Track Patterns Between UHMWPE/Steel and UHMWPE/CNx Pairs2012In: Procedia Materials Science, ISSN 2211-8128, Vol. 1, p. 329-336Article in journal (Refereed)
    Abstract [en]

    This work explores the effect of surface modification of stainless steel with a carbon nitride (CNx) film, under sliding wear of the UHMWPE/steel. Wettatibility of CNx coatings is assessed by means of the sessile drop method using two different liquid media. Microhardness and stiffness of CNx coatings are estimated by depth-sensing indentation. The sliding performance of UHMWPE against stainless steel and CNx was evaluated using a pin on disk tribometer. It is demonstrated that CNx surface properties are quite different from those of stainless steel, with a concomitant substantial reduction of the coefficient of friction of UHMWPE/CNx in comparison with the one of UHMWPE/steel under sliding conditions. Even tough imposed sliding conditions do not conduct to wear mass loss in UHMWPE, wear track patterns against steel and CNx are quite different.

  • 38.
    De Feudis, M.
    et al.
    University of Salento, Italy; INFN National Institute Nucl Phys, Italy.
    Caricato, A. P.
    University of Salento, Italy; INFN National Institute Nucl Phys, Italy.
    Taurino, A.
    CNR IMM Institute Microelect and Microsyst, Italy.
    Ossi, P. M.
    Politecn Milan, Italy.
    Castiglioni, C.
    Politecn Milan, Italy.
    Brambilla, L.
    Politecn Milan, Italy.
    Maruccio, G.
    NNL CNR Nanotec, Italy.
    Monteduro, A. G.
    NNL CNR Nanotec, Italy.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Chiodini, G.
    INFN National Institute Nucl Phys, Italy.
    Martino, M.
    University of Salento, Italy; INFN National Institute Nucl Phys, Italy.
    Diamond graphitization by laser-writing for all-carbon detector applications2017In: Diamond and related materials, ISSN 0925-9635, E-ISSN 1879-0062, Vol. 75, p. 25-33Article in journal (Refereed)
    Abstract [en]

    The surface of a detector grade CVD polycrystalline diamond sample (5 x 5 x 0.05 mm(3)) was irradiated by an ArF excimer laser (lambda = 193 nm, T = 20 ns) to produce graphitic conductive layers. In particular, two sets of four parallel graphitic strip-like contacts, with 1 mm pitch, were created along the whole sample on the top and on the rear surfaces of the sample respectively. The two series of stripes lie normally to each other. Such a grid allows to obtain a segmented all-carbon device capable of giving bi-dimensional information on particle detection processes in nuclear applications. Afterwards, an extensive characterization of the samples was performed: SEM and micro-Raman investigations to study the morphological and structural evolution of the irradiated areas, EDS measurements to individuate any absorption phenomena from environment associated to laser treatment, and nanoindentation mapping to understand how the hard-soft transformation occurred depending on the locally transferred energy. Finally, current-voltage analyses were carried out checking the ohmic behavior of the diamond-graphite contact. By comparing the results of the different characterization analyses, a strong periodidty of the modified surface properties was found, confirming the reliability and reproducibility of the laser-induced graphitization process. The results demonstrate that the laser-writing technique is a good and fast solution to produce graphitic contacts on diamond surface and therefore represents a promising way to fabricate segmented all-carbon devices. (C) 2016 Elsevier B.V. All rights reserved.

  • 39.
    De Rosa, Horacio
    et al.
    Laboratorio de metulografia, Facultad de Ingenieria UBA, Buenos Aries, Argentina.
    Cardus, Gustavo
    Laboratorio de metulografia, Facultad de Ingenieria UBA, Buenos Aries, Argentina.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Zimmerman, Rosa
    Laboratorio de Peliculas Delgudas, Facultad de IngenieriLaboratorio de Peliculas Delgadas, Facultad de Ingenieria UBA, Buenos Aries, Argentina.
    Propiedades Tribológicas de Películas de AlSn Depositadas por Magnetron Sputtering [Tribological Properties of AlSn Thin Films Deposited by Magnetron Sputtering]2000In: Anales AFA, ISSN 1850-1158, Vol. 11, no 1, p. 195-198Article in journal (Refereed)
    Abstract [en]

    In this paper structural and tribological properties of thin films, made with the bimetal 20AlSn used as solid lubricant in the automotive industry, were studied. Films with thicknesses in the range 150 nm to 3μm were deposited by magnetron sputtering. It is found that in the thinner films predominates a diffusion growth mechanism, while for larger thicknesses it is observed an aggregation growth mechanism. A finely dispersed structure of uniform particle size and shape, vital for good tribological behavior, is obtained.

  • 40.
    Diliegros-Godines, C. J.
    et al.
    CINVESTAV, Querétaro, Mexico.
    Flores-Ruiz, Francisco
    CINVESTAV, Querétaro, Mexico.
    Castanedo-Pérez, R.
    CINVESTAV, Querétaro, Mexico.
    Torres-Delgado, G.
    CINVESTAV, Querétaro, Mexico.
    Espinoza-Beltrán, F. J.
    CINVESTAV, Querétaro, Mexico.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Mechanical and tribological properties of CdO + SnO2 thin films prepared by sol–gel2015In: Journal of Sol-Gel Science and Technology, ISSN 0928-0707, E-ISSN 1573-4846, Vol. 74, no 1, p. 114-120Article in journal (Refereed)
    Abstract [en]

    We report the mechanical and tribological properties of transparent conductive oxide CdO + SnO2 coatings. The films were deposited on glass substrates by the sol–gel technique using, as precursor solution, a mixture of CdO and SnO2 solutions obtained at room temperature. Depending on the Sn atomic concentration percentage values the X-ray diffraction patterns show three types of films constituted of (1) CdO + Cd2SnO4, (2) Cd2SnO4 and (3) Cd2SnO4 + CdSnO3 crystals. Reciprocal microfriction tests revealed that films with Cd2SnO4 phase have friction values in the range 0.48–0.51 and a low wear rate of ~5 × 10−5 mm3 N−1 m−1. Nanoindentation tests have shown an increment of the elastic modulus from 50 GPa for CdO + Cd2SnO4 films to 90 GPa for Cd2SnO4 films, while the hardest coating was the one constituted by Cd2SnO4 crystals with H = 5.7 GPa, comparable to the hardness and elastic modulus reported for ITO films.

  • 41.
    Eriksson, Robert
    et al.
    Siemens Industrial Turbomachinery AB, Berlin, Germany.
    Gupta, Mohit
    University West, Trollhättan, Sweden.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Jonnalagadda, Krisha Praveen
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    Nylén, Per
    University West, Trollhättan, Sweden.
    Peng, Ru
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, Faculty of Science & Engineering.
    Stresses and Cracking During Chromia-Spinel- NiO Cluster Formation in TBC Systems2015In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 24, no 6, p. 1002-1014Article in journal (Refereed)
    Abstract [en]

    Thermal barrier coatings (TBC) are used in gas turbines to reduce the temperatures in the underlying substrate. There are several mechanisms that may cause the TBC to fail; one of them is cracking in the coating interface due to extensive oxidation. In the present study, the role of so called chromia-spinel-NiO (CSN) clusters in TBC failure was studied. Such clusters have previously been found to be prone to cracking. Finite element modeling was performed on a CSN cluster to find out at which stage of its formation it cracks and what the driving mechanisms of cracking are. The geometry of a cluster was obtained from micrographs and modeled as close as possible. Nanoindentation was performed on the cluster to get the correct Young’s moduli. The volumetric expansion associated with the formation of NiO was also included. It was found that the cracking of the CSN clusters is likely to occur during its last stage of formation as the last Ni-rich core oxidizes. Furthermore, it was shown that the volumetric expansion associated with the oxidation only plays a minor role and that the main reason for cracking is the high coefficient of thermal expansion of NiO.

  • 42.
    Eriksson, Robert
    et al.
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Johansson, Sten
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Brodin, Håkan
    Linköping University, Department of Management and Engineering, Engineering Materials. Linköping University, The Institute of Technology.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Östergren, Lars
    GKN Aerospace Engine Systems, Trollhättan, Sweden.
    Li, Xin-Hai
    Siemens Industrial Turbomachinery AB, Finspång, Sweden.
    Influence of substrate material on the life of atmospheric plasmas prayed thermal barrier coatings2013In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 232, no 15, p. 795-803Article in journal (Refereed)
    Abstract [en]

    Thermal barrier coatings (TBCs) are used in gas turbines to prolong the life of the underlying substrates and to increase the efficiency of the turbines by enabling higher combustion temperatures. TBCs may fail during service due to thermal fatigue or through the formation of non-protective thermally grown oxides (TGOs). This study compares two atmospheric plasma sprayed (APS) TBC systems comprising of two identical TBCs deposited on two different substrates (Haynes 230 and Hastelloy X). The thermal fatigue life was found to differ between the two TBC systems. The interdiffusion of substrate elements into the coating was more pronounced in the TBC system with shorter life, however, very few of the substrate elements (only Mn and to some extent Fe) formed oxides in the bond coat/top coat interface. Fractography revealed no differences in the fracture behaviour of the TBCs; the fracture occurred, in both cases, to about 60% in the top coat close to the interface and the remainder in the interface. Nanoindentation revealed only small differences in mechanical properties between the TBC systems and a finite element crack growth analysis showed that such small differences did not cause any significant change in the crack driving force. The oxidation kinetics was found to be similar for both TBC systems for the formation of Al2O3 but differed for the kinetics of non-Al2O3 TGOs where the TBC system with shortest life had a faster formation of non-Al2O3 TGOs caused by a faster Al depletion. The difference in non-Al2O3 TGO growth kinetics was considered to be the main reason for the difference in life.

  • 43.
    Gervacio-Arciniega, J. J.
    et al.
    University of Nacl Autonoma Mexico, Mexico.
    Flores-Ruiz, F. J.
    University of Nacl Autonoma Mexico, Mexico.
    Diliegros-Godines, C. J.
    University of Nacl Autonoma Mexico, Mexico.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Enriquez-Flores, C. I.
    CINVESTAV, Mexico.
    Espinoza-Beltran, F. J.
    CINVESTAV, Mexico.
    Siqueiros, J.
    University of Nacl Autonoma Mexico, Mexico.
    Cruz, M. P.
    University of Nacl Autonoma Mexico, Mexico.
    Nanofrictional behavior of amorphous, polycrystalline and textured Y-Cr-O films2016In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 378, p. 157-162Article in journal (Refereed)
    Abstract [en]

    Differences in friction coefficients (mu) of ferroelectric YCrO3, textured and polycrystalline films, and non-ferroelectric Y-Cr-O films are analyzed. The friction coefficient was evaluated by atomic force microscopy using a simple quantitative procedure where the dependence of friction force with the applied load is obtained in only one topographical image. A simple code was developed with the MATLAB (R) software to analyze the experimental data. The code includes a correction of the hysteresis in the forward and backward scanning directions. The quantification of load exerted on the sample surface was obtained by finite element analysis of the AFM cantilever starting from its experimental dynamic information. The results show that the ferroelectric YCrO3 film deposited on a Pt(150 nm)/TiO2(30 nm)/SiO2/Si (100) substrate is polycrystalline and has a lower friction coefficient than the deposited on SrTiO3 (110), which is highly textured. From a viewpoint of industrial application in ferroelectric memories, where the writing process is electrical or mechanically achieved by sliding AFM tips on the sample, polycrystalline YCrO3 films seem to be the best candidates due to their lower mu, (C) 2016 Elsevier B.V. All rights reserved.

  • 44.
    Gontad, F
    et al.
    University of Salento, Department of Mathematics and Physics.
    Lorusso, A
    University of Salento, Department of Mathematics and Physics.
    Panareo, M
    University of Salento, Department of Mathematics and Physics.
    Monteduro, A
    University of Salento, Department of Mathematics and Physics.
    Maruccio, G
    University of Salento, Department of Mathematics and Physics.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Perrone, A
    University of Salento, Department of Mathematics and Physics.
    Nanomechanical and electrical properties of Nb thin films deposited on Pb substrates by pulsed laser deposition as a new concept photocathode for superconductor cavities2015In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 804, p. 132-136Article in journal (Refereed)
    Abstract [en]

    We report a design of photocathode, which combines the good photoemissive properties of lead (Pb) and the advantages of superconducting performance of niobium (Nb) when installed into a superconducting radio-frequency gun. The new configuration is obtained by a coating of Nb thin film grown on a disk of Pb via pulsed laser deposition. The central emitting area of Pb is masked by a shield to avoid the Nb deposition. The nanomechanical properties of the Nb film, obtained through nanoindentation measurements, reveal a hardness of 2.8±0.3 GPa, while the study of the electrical resistivity of the film shows the appearance of the superconducting transitions at 9.3 K and 7.3 K for Nb and Pb, respectively, very close to the bulk material values. Additionally, morphological, structural and contamination studies of Nb thin film expose a very low droplet density on the substrate surface, a small polycrystalline orientation of the films and a low contamination level. These results, together with the acceptable Pb quantum efficiency of 2×10−5 found at 266 nm, demonstrate the potentiality of the new concept photocathode.

  • 45.
    Gontad, Francisco
    et al.
    University of Salento, Italy.
    Lorusso, Antonella
    University of Salento, Italy.
    Di Giulio, Massimo
    University of Salento, Italy.
    Eriksson, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Perrone, Alessio
    University of Salento, Italy.
    Growth of lead thin films on silicon and niobium substrates by sputtering technique2017In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 35, no 3, article id 031502Article in journal (Refereed)
    Abstract [en]

    In this paper, the authors report the growth of Pb thin films on both Si and Nb substrates by radio-frequency sputtering technique. Deposited films were characterized and tested to deduce the structure, the morphology, the nanomechanical properties, and also the quantum efficiency. Granular structures and large presence of voids were observed by scanning electron microscopy; moreover, the roughness and grain size of the film surface, investigated by surface probe microscopy, increased with the film thickness. Crystallographic orientation, studied by x-ray diffraction, showed the growth of polycrystalline Pb thin films and the presence of weak diffraction peaks related to penta-lead oxide (Pb5O8). The nanomechanical analysis reveals a film hardness with a value (similar to 1.5GPa) well beyond the hardness of Pb bulk (0.04GPa). Finally, twin Pb thin films deposited on Nb substrates were tested as photocathodes showing its great potentiality to be used in superconducting radio-frequency guns with a quantum efficiency of 5 x 10(-5). (C) 2017 American Vacuum Society.

  • 46.
    Gontad, Francisco
    et al.
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Lorusso, Antonella
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Klini, Argyro
    Fdn Research and Technology Hellas FORTH, Greece.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Perrone, Alessio
    University of Salento, Italy; Ist Nazl Fis Nucl, Italy.
    Fotakis, Costas
    Fdn Research and Technology Hellas FORTH, Greece.
    Fabrication of Nb/Pb structures through ultrashort pulsed laser deposition2016In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 34, no 4, article id 041501Article in journal (Refereed)
    Abstract [en]

    This work reports the fabrication of Nb/Pb structures with an application as photocathode devices. The use of relatively low energy densities for the ablation of Nb with ultrashort pulses favors the reduction of droplets during the growth of the film. However, the use of laser fluences in this ablation regime results in a consequent reduction in the average deposition rate. On the other hand, despite the low deposition rate, the films present a superior adherence to the substrate and an excellent coverage of the irregular substrate surface, avoiding the appearance of voids or discontinuities on the film surface. Moreover, the low energy densities used for the ablation favor the growth of nanocrystalline films with a similar crystalline structure to the bulk material. Therefore, the use of low ablation energy densities with ultrashort pulses for the deposition of the Nb thin films allows the growth of very adherent and nanocrystalline films with adequate properties for the fabrication of Nb/Pb structures to be included in superconducting radiofrequency cavities. (C) 2016 American Vacuum Society.

  • 47.
    Gåård, Anders
    et al.
    Karlstad University.
    Karlsson, Patrik
    Karlstad University.
    Krakhmalev, Pavel
    Karlstad University.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Nano-scale friction of multi-phase powder metallurgy tool steels2015In: Advanced Materials Research, ISSN 1022-6680, E-ISSN 1662-8985, Vol. 1119, p. 70-74Article in journal (Refereed)
    Abstract [en]

    Friction is a fundamental phenomenon in tribology involving complex mechanisms between thecontacting surfaces. Measurements of friction are often made using devices with substantially largercontact area than dimensions corresponding to microstructural features of the materials. Hence, for multi-phase materials,influence of particular microstructural constituents is not resolved. In the present work, a tribometerwith a contact area in the nano-scale range was used to map friction for different types of tool steelswith different chemical- and phase composition. Owing to the small tip radius, frictionalcharacteristics of primary carbides and the steel matrix were measured and compared. Dependingon chemical composition, a difference was observed where the coefficient of friction wasapproximately twice higher for the steel possessing highest coefficient of friction, including bothcarbides and the steel matrix.

  • 48.
    Hussain, Mushtaque
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Khan, Azam
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Educational Sciences.
    Nur, Omer
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    The effect of oxygen-plasma treatment on the mechanical andpiezoelectrical properties of ZnO nanorods2014In: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 608, p. 235-238Article in journal (Refereed)
    Abstract [en]

    We have studied the effect of oxygen plasma treatment on piezoelectric response and on the mechanical stability of ZnO nanorods synthesized on FTO by using ACG method. XRD and SEM techniques have shown highly dense and uniformly distributed nanorods. The piezoelectric properties and mechanical stability of as-grown and oxygen plasma treated samples were investigated by using nanoindentation technique. The comparison of load–displacement curves showed that the oxygen plasma treated samples are much stiffer and show higher generated piezo-voltage. This study demonstrates that the oxygenplasma treatment is a good option to fabricate reliable and efficient nanodevices for enhanced generation of piezoelectricity.

  • 49.
    Högberg, Hans
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Tengdelius, Lina
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Samuelsson, Mattias
    Impact Coatings AB, Linköping, Sweden .
    Eriksson, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Arts and Sciences.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Reactive sputtering of delta-ZrH2 thin films by high power impulse magnetron sputtering and direct current magnetron sputtering2014In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 32, no 4, p. 041510-Article in journal (Refereed)
    Abstract [en]

    Reactive sputtering by high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) of a Zr target in Ar/H-2 plasmas was employed to deposit Zr-H films on Si(100) substrates, and with H content up to 61 at.% and O contents typically below 0.2 at.% as determined by elastic recoil detection analysis. X-ray photoelectron spectroscopy reveals a chemical shift of similar to 0.7 eV to higher binding energies for the Zr-H films compared to pure Zr films, consistent with a charge transfer from Zr to H in a zirconium hydride. X-ray diffraction shows that the films are single-phase delta-ZrH2 (CaF2 type structure) at H content greater thansimilar to 55 at.% and pole figure measurements give a 111 preferred orientation for these films. Scanning electron microscopy cross-section images show a glasslike microstructure for the HiPIMS films, while the DCMS films are columnar. Nanoindentation yield hardness values of 5.5-7 GPa for the delta-ZrH2 films that is slightly harder than the similar to 5 GPa determined for Zr films and with coefficients of friction in the range of 0.12-0.18 to compare with the range of 0.4-0.6 obtained for Zr films. Wear resistance testing show that phase-pure delta-ZrH2 films deposited by HiPIMS exhibit up to 50 times lower wear rate compared to those containing a secondary Zr phase. Four-point probe measurements give resistivity values in the range of similar to 100-120 mu Omega cm for the delta-ZrH2 films, which is slightly higher compared to Zr films with values in the range 70-80 mu Omega cm.

  • 50.
    Javier Flores-Ruiz, Francisco
    et al.
    Benemerita University of Autonoma Puebla, Mexico.
    Janani Diliegros-Godines, Carolina
    Benemerita University of Autonoma Puebla, Mexico.
    Alejandro Hernandez-Garcia, F.
    IPN, Mexico.
    Castanedo-Perez, Rebeca
    IPN, Mexico.
    Torres-Delgado, Gerardo
    IPN, Mexico.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Mechanical and tribological behavior of sol-gel TiO2-CdO films measured at the microscale levels2017In: Journal of Sol-Gel Science and Technology, ISSN 0928-0707, E-ISSN 1573-4846, Vol. 82, no 3, p. 682-691Article in journal (Refereed)
    Abstract [en]

    In this work, we present a mechanical and tribological study at the microscale of sol-gel TiO2-CdO films, which are used in photocatalytic applications. The films were deposited as a good-quality polycrystalline material with majority of CdO or CdTiO3 phases depending on their Ti/Cd concentration ratios. Films with the majority of CdTiO3 phase presented the highest hardness and lowest plastic deformation during the indentation tests. The evolution of wear, friction coefficient, and roughness on the films was quantitatively studied by multiple-passes measurements on a depth-sensing instrumented indentation system. These measurements allowed us to observe the films wear mechanisms and correlate them with their microstructure and mechanical properties. To compare the crystal structure, mechanical properties and tribological behavior of these films, we also analyzed sol-gel CdO and TiO2 films deposited under similar conditions.

12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf