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Fager, Hanna
Publications (10 of 10) Show all publications
Fager, H., Howe, B. M., Greczynski, G., Jensen, J., Mei, A. B., Lu, J., . . . Petrov, I. (2015). Novel hard, tough HfAlSiN multilayers, defined by alternating Si bond structure, deposited using modulated high-flux, low-energy ion irradiation of the growing film. Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, 33(5), 05E103-1-05E103-9
Open this publication in new window or tab >>Novel hard, tough HfAlSiN multilayers, defined by alternating Si bond structure, deposited using modulated high-flux, low-energy ion irradiation of the growing film
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2015 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 33, no 5, p. 05E103-1-05E103-9Article in journal (Refereed) Published
Abstract [en]

Hf1-x-yAlxSiyN (0 less than= x less than= 0.14, 0 less than= y less than= 0.12) single layer and multilayer films are grown on Si(001) at 250 degrees C using ultrahigh vacuum magnetically unbalanced reactive magnetron sputtering from a single Hf0.6Al0.2Si0.2 target in mixed 5%-N-2/Ar atmospheres at a total pressure of 20 mTorr (2.67 Pa). The composition and nanostructure of Hf1-x-yAlxSiyN films are controlled by varying the energy Ei of the ions incident at the film growth surface while maintaining the ion-to-metal flux ratio constant at eight. Switching E-i between 10 and 40 eV allows the growth of Hf0.78Al0.10Si0.12N/Hf0.78Al0.14Si0.08N multilayers with similar layer compositions, but in which the Si bonding state changes from predominantly Si-Si/Si-Hf for films grown with E-i = 10 eV, to primarily Si-N with E-i = 40 eV. Multilayer hardness values, which vary inversely with bilayer period Lambda, range from 20 GPa with Lambda = 20 nm to 27 GPa with Lambda = 2 nm, while fracture toughness increases directly with Lambda. Multilayers with Lambda = 10nm combine relatively high hardness, H similar to 24GPa, with good fracture toughness. (C) 2015 American Vacuum Society.

Place, publisher, year, edition, pages
A V S AMER INST PHYSICS, 2015
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:liu:diva-121905 (URN)10.1116/1.4920980 (DOI)000361229000003 ()
Note

Funding Agencies|U.S. Department of Energy [DE-FG02-07ER46453, DE-FG02-07ER46471]; Swedish Foundation for Strategic Research project Designed Multicomponent Coatings, MultiFil; U.S. Department of Defense Science, Mathematics, and Research for Transformation program; Swedish Government Strategic Research Area Grant (SFO MAT-LiU) on Advanced Functional Materials; Swedish Research Council (VR) [2009-00971]

Available from: 2015-10-13 Created: 2015-10-12 Last updated: 2017-12-01
Fager, H. (2014). Growth and Characterization of Amorphous Multicomponent Nitride Thin Films. (Doctoral dissertation). Linköping: Linköping University Electronic Press
Open this publication in new window or tab >>Growth and Characterization of Amorphous Multicomponent Nitride Thin Films
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis explores deposition of amorphous thin films based on the two transition metal nitride systems, TiN and HfN. Additions of Si, Al and B have been investigated using three different deposition techniques: dc magnetron sputtering, cathodic arc evaporation, and high power impulse magnetron sputtering (HIPIMS). The effect of elemental composition, bonding structure, growth temperature, and low-energy ion bombardment during growth has been investigated and correlated to the resulting microstructure and mechanical properties of the films. The thermal stability has been investigated by annealing experiments.

Deposition by cathodic arc evaporation yields dense and homogeneous coatings with essentially fully electron-diffraction amorphous structures with additions of either Al+Si, B+Si or B+Al+Si to TiN. The B-containing coatings have unusually few macroparticles. Annealing experiments show that Ti-Al-Si-N coatings have an age hardening behavior, which is not as clear for B-containing coatings. Compositional layering, due to rotation of the sample fixture during deposition, is present but not always visible in the as-deposited state. The layering acts as a template for renucleation during annealing. The coatings recrystallize by growth of TiN-rich  domains.

Amorphous growth by conventional dc magnetron sputtering is possible over a wide range of compositions for Ti-B-Si-N thin films. The Ti content in the films is reduced compared to the content in the sputtering target. Without Si, the films consist of a BN onion-like structure surrounding TiN nanograins. With additions of Si the films eventually grows fully amorphous. The growth temperature has only minor effect on the microstructure, due to the limited surface diffusion at the investigated temperature range (100-600 °C). Ion assisted growth leads to nanoscale densification of the films and improved mechanical properties.

Ti-B-Si-N thin films are also deposited by a hybrid technique where dc magnetron sputtering is combined with HIPIMS. Here, the Ti:B ratio remains equal to the target composition. Films with low Si content are porous with TiN nanograins separated by BN-rich amorphous channels and have low hardness. Increasing Si contents yield fully electron-amorphous films with higher hardness.

Finally, Hf-Al-Si-N single-layer and multilayer films are grown by dc magnetron sputtering from a single Hf-Al-Si target. Amorphous growth is achieved when the growth temperature was kept at its minimum. Low-energy substrate bias modulation is used to grow nanocomposite/nanocolumnar multilayers from the single Hf-Al-Si target, where the layers has essentially the same composition but different Si bonding structure, and different degree of crystallinity.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2014. p. 92
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1595
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-106576 (URN)10.3384/diss.diva-106576 (DOI)978-91-7519-337-3 (ISBN)
Public defence
2014-05-28, Planck, Fysikhuset, Campus Valla, Linköping, 10:00 (English)
Opponent
Supervisors
Available from: 2014-05-12 Created: 2014-05-12 Last updated: 2016-08-31Bibliographically approved
Fager, H., Greczynski, G., Jensen, J., Lu, J. & Hultman, L. (2014). Growth and properties of amorphous Ti-B-Si-N thin films deposited by hybrid HIPIMS/DC-magnetron co-sputtering from TiB2 and Si targets. Surface & Coatings Technology, 259, 442-447
Open this publication in new window or tab >>Growth and properties of amorphous Ti-B-Si-N thin films deposited by hybrid HIPIMS/DC-magnetron co-sputtering from TiB2 and Si targets
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2014 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 259, p. 442-447Article in journal (Refereed) Published
Abstract [en]

Amorphous nitrides are explored for their homogenous structure and potential use as wear-resistant coatings, beyond their much studied nano-and microcrystalline counterparts. (TiB2)1−xSixNy thin films were deposited on Si(001) substrates by a hybrid technique of high power impulse magnetron sputtering (HIPIMS) combined with dc magnetron sputtering (DCMS) using TiB2 and Si targets in a N2/Ar atmosphere. By varying the sputtering dc power to the Si target from 200 to 2000 W while keeping the average power to the TiB2-target, operated in HIPIMS mode, constant at 4000 W, the Si content in the films increased gradually from x=0.01 to x=0.43. The influence of the Si content on the microstructure, phase constituents, and mechanical properties were systematically investigated. The results show that the microstructure of as-deposited (TiB2)1−xSixNy films changes from nanocrystalline with 2-4 nm TiN grains for x=0.01 to fully electron diffraction amorphous for x=0.22. With increasing Si content, the hardness of the films increases from 8.5 GPa with x=0.01 to 17.2 GPa with x=0.43.

Place, publisher, year, edition, pages
Elsevier, 2014
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-106574 (URN)10.1016/j.surfcoat.2014.10.053 (DOI)000347605200010 ()
Available from: 2014-05-12 Created: 2014-05-12 Last updated: 2017-12-05Bibliographically approved
Fager, H., Howe, B., Greczynski, G., Jensen, J., Mei, A. R., Lu, J., . . . Hultman, L. (2014). Hf-Al-Si-N multilayers deposited by reactive magnetron sputtering from a single Hf0.6Al0.2Si0.2 target using high-flux, low-energy modulated substrate bias: film growth and properties.
Open this publication in new window or tab >>Hf-Al-Si-N multilayers deposited by reactive magnetron sputtering from a single Hf0.6Al0.2Si0.2 target using high-flux, low-energy modulated substrate bias: film growth and properties
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2014 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Hf1−x−yAlxSiyN (0≤x≤0.14, 0≤y≤0.13) single layers and multilayer films are grown on Si(001) at a substrate temperature Ts=250 °C using ultrahigh vacuum magnetically-unbalanced reactive magnetron sputtering from a single Hf0.6Al0.2Si0.2 target in a 5%-N2/Ar atmosphere at a total pressure of 20 mTorr (2.67 Pa). The composition and nanostructure of Hf1−x−yAlxSiyN is controlled during growth by varying the ion energy (Ei) of the ions incident at the film surface, keeping the ion-to-metal flux ratio (Ji/JMe) constant at 8. By sequentially switching Ei between 10 and 40 eV, Hf0.77Al0.10Si0.13N/Hf0.78Al0.14Si0.08N multilayers with bilayer periods Λ = 2-20 nm are grown, in which the Si2p bonding state changes from predominantly Si-Si bonds for films grown at Ei = 10 eV, to mainly Si-N bonds at Ei = 40 eV. Multilayer hardness values increase monotonically from 20 GPa with Λ = 20 nm to 27 GPa with Λ = 2 nm, while multilayer fracture toughness increases with increasing Λ. Multilayers with Λ = 10 nm have the optimized property combination of being bothrelatively hard, H∼24 GPa, and fracture tough.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-106575 (URN)
Available from: 2014-05-12 Created: 2014-05-12 Last updated: 2016-08-31Bibliographically approved
Fager, H., Eriksson, F., Lu, J., Jensen, J. & Hultman, L. (2014). Reactive DC magnetron sputtering of amorphous (Ti0.25B0.75)1−xSixNy thin films from TiB2 and Si targets.
Open this publication in new window or tab >>Reactive DC magnetron sputtering of amorphous (Ti0.25B0.75)1−xSixNy thin films from TiB2 and Si targets
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2014 (English)Manuscript (preprint) (Other academic)
Abstract [en]

(Ti0.25B0.75)1−xSixNy, 0≤x≤0.89, 0.9≤y≤1.25, thin films were reactively grown on Si(001) substrates by dc magnetron sputtering from compound TiB2 and elemental Si targets. The films can be grown in a fully electron-diffraction amorphous state with x>0.46, as evidenced by XRD and HR-TEM investigations. With x=0, BN form onion-like sheets surrounding TiNnanograins. Substrate temperatures, Ts=100-600 ◦C, has a minor effect of the film structure and properties, due to limited surface diffusion.

Ion-assisted growth with substrate bias voltages, Vb, between -50 V and -200 V, favors densification of amorphous structures over nanocrystalline formation, and improves mechanical properties. A maximum hardness value of 26.8±0.7 GPa is found for an amorphous (Ti0.25B0.75)0.39Si0.61N1.15 film grown with substrate temperature Ts=400 °C and substrate bias voltage Vb=-100 V.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-106572 (URN)
Available from: 2014-05-12 Created: 2014-05-12 Last updated: 2016-08-31Bibliographically approved
Fager, H., Andersson, J., Jensen, J., Lu, J. & Hultman, L. (2014). Thermal stability and mechanical properties of amorphous arc evaporated Ti-B-Si-N and Ti-B-Si-Al-N coatings grown by cathodic arc evaporation from TiB2, Ti33Al67, and Ti85Si15 cathodes. Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, 32(6), 061508
Open this publication in new window or tab >>Thermal stability and mechanical properties of amorphous arc evaporated Ti-B-Si-N and Ti-B-Si-Al-N coatings grown by cathodic arc evaporation from TiB2, Ti33Al67, and Ti85Si15 cathodes
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2014 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 32, no 6, p. 061508-Article in journal (Refereed) Published
Abstract [en]

Ti-B-Al-N, Ti-B-Si-N, and Ti-B-Si-Al-N coatings were grown on cemented carbide substrates in an industrial scale cathodic arc evaporation system using Ti33Al67, Ti85Si15, and TiB2 cathodes in a reactiveN2 atmosphere. The microstructure of the as-deposited coatings changes from nanocrystalline to amorphous with addition of (B+Si+Al), or high amounts of (B+Si) to TiN. In the as-deposited state, the 4 μm-thick amorphous coatings are dense and homogenous, besides slight compositional modulation with Ti-rich layers induced by rotation of the substrate holder fixture during deposition, and have unusually few macroparticles. Annealing at temperatures ranging from 700 °C to 1100 °C results in that the coatings crystallize by clustering of TiN grains. The hardness of as-deposited amorphous coatings is 17-18 GPa, and increases to 21 GPa following annealing at 800 °C. At annealing temperatures of 1000 °C and above the hardness decreases due to inter-diffusion of Co from the substrate to the coating.

Place, publisher, year, edition, pages
American Vacuum Society, 2014
National Category
Physical Sciences
Identifiers
urn:nbn:se:liu:diva-106573 (URN)10.1116/1.4897170 (DOI)000345215500021 ()
Available from: 2014-05-12 Created: 2014-05-12 Last updated: 2017-12-05Bibliographically approved
Fager, H., Andersson, J. M., Johansson, M., Odén, M. & Hultman, L. (2013). Growth of Hard Amorphous Ti-Al-Si-N Thin Films by Cathodic Arc Evaporation. Surface & Coatings Technology, 235(25), 376-385
Open this publication in new window or tab >>Growth of Hard Amorphous Ti-Al-Si-N Thin Films by Cathodic Arc Evaporation
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2013 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 235, no 25, p. 376-385Article in journal (Refereed) Published
Abstract [en]

Ti(1−x−y)AlxSiyNz (0.02≤x≤0.46, 0.02≤y≤0.28, and 1.08≤z≤1.29) thin films were grown on cemented carbide substrates in an industrial scale cathodic arc evaporation system using Ti-Al-Si compound cathodes in a N2 atmosphere. The microstructure of the as-deposited films changes from nanocrystalline to amorphous by addition of Al and Si to TiN. Upon incorporation of 12 at% Si and 18 at% Al, the films assume an x-ray amorphous state. Post-deposition anneals show that the films are thermally stable up to 900 ◦C. The films exhibit age hardening up to 1000 ◦C with an increase in hardness from 21.9 GPa for as-deposited films to 31.6 GPa at 1000 ◦C. At 1100 ◦C severe out-diffusion of Co and W from the substrate occur, and the films recrystallize into c-TiN and w-AlN.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-80199 (URN)10.1016/j.surfcoat.2013.07.014 (DOI)000329596100048 ()
Available from: 2012-08-22 Created: 2012-08-22 Last updated: 2018-01-03Bibliographically approved
Fallqvist, A., Ghafoor, N., Fager, H., Hultman, L. & Persson, P. O. (2013). Self-organization during Growth of ZrN/SiNx Multilayers by Epitaxial Lateral Overgrowth. Journal of Applied Physics, 114(224302)
Open this publication in new window or tab >>Self-organization during Growth of ZrN/SiNx Multilayers by Epitaxial Lateral Overgrowth
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2013 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 114, no 224302Article in journal (Refereed) Published
Abstract [en]

ZrN/SiNx nanoscale multilayers were deposited on ZrN seed layers grown on top of MgO(001) substrates by dc magnetron sputtering with a constant ZrN thickness of 40 Å and with an intended SiNx thickness of 2, 4, 6, 8, and 15 Å at a substrate temperature of 800 °C and 6 Å at 500 °C. The films were investigated by X-ray diffraction, high-resolution scanning transmission electron microscopy, and energy dispersive X-ray spectroscopy. The investigations show that the SiNx is amorphous and that the ZrN layers are crystalline. Growth of epitaxial cubic SiNx – known to take place on TiN(001) – on ZrN(001) is excluded to the monolayer resolution of this study. During the course of SiNx deposition, the material segregates to form surface precipitates in discontinuous layers for SiNx thicknesses ≤ 6 Å that coalesce into continuous layers for 8 and 15 Å thickness at 800 °C, and for 6 Å at 500 °C. The SiNx precipitates are aligned vertically. The ZrN layers in turn grow by epitaxial lateral overgrowth on the discontinuous SiNx in samples deposited at 800 °C with up to 6 Å thick SiNx layers. Effectively a self-organized nanostructure can be grown consisting of strings of 1-3 nm large SiNx precipitates along apparent column boundaries in the epitaxial ZrN.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-102173 (URN)10.1063/1.4838495 (DOI)000329090400072 ()
Available from: 2013-12-02 Created: 2013-12-02 Last updated: 2017-12-06Bibliographically approved
Fager, H. (2012). Growth and Characterization of Amorphous TiAlSiN and HfAlSiN Thin Films. (Licentiate dissertation). Linköping: Linköping University Electronic Press
Open this publication in new window or tab >>Growth and Characterization of Amorphous TiAlSiN and HfAlSiN Thin Films
2012 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

This Thesis explores amorphous transition metal nitrides for cutting tool applications. The aim is to extend the knowledge on amorphous nitride thin lms, to describe the growth process, and to explore ways of characterizing these novel complex materials.

Thin lms of Ti-Al-Si-N and Hf-Al-Si-N were fabricated using industrial cathodic arc evaporation and magnetically-unbalanced reactive magnetron sputtering, respectively. The microstructure of the lms was studied using x-ray diraction (XRD) and transmission electron microscopy (TEM), while compositional analysis of the lms was performed by spectroscopic techniques (EDS, SIMS, and RBS). The mechanical properties were investigated by nanoindentation.

The Ti-Al-Si-N lms were grown on cemented carbide substrates using Ti-Al-Si compound cathodes in an N2 atmosphere. High Al and Si concentrations in the lms (i.e., 12 at% Si and 18 at% Al) promote renucleation and result in x-ray amorphous lms. High resolution TEM (HRTEM) reveals isolated grains, ~2 nm in size, embedded in an amorphous matrix. Annealing experiments show that the lms are thermally stable up to 900 oC. They exhibit age hardening, with an increase in hardness from 21.9 GPa for as-deposited lms to 31.6 GPa at 1000 oC. At 1100 oC severe out-diusion of Co and W from the substrate occurs, and the lms recrystallize into c-TiN and w-AlN.

The single layer Hf-Al-Si-N and multilayer Hf-Al-Si-N/HfN lms were grown on Si(001) substrates from a single Hf0:60Al0:20Si0:20 alloy target in an N2/Ar atmosphere. The composition and nanostructure of the lms was controlled during growth by independently varying the ion energy (Ei) and the ion-to-metal flux ratio (Ji=JMe). With Ji/JMe=8, the nanostructure and composition of the lms changes from x-ray amorphous with a Hf content of 0.6, to an amorphous matrix with encapsulated nanocrystals with 0.66≤Hf≤0.84, to nanocrystalline with 0.96≤Hf≤1.00, when increasing Ei from 15 to 65 eV. Varying Ji=JMe with Ei=13 eV yields electron-diraction amorphous lms at substrate temperatures of 100 oC. Hf-Al-Si-N/HfN multilayers with periods Λ=2-20 nm exhibit enhanced fracture toughness compared to polycrystalline VN, TiN, and Ti0:5Al0:5N reference samples; multilayer hardness values increase from 20 GPa with Λ=20 nm to 27 GPa with Λ=2 nm.

̴

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2012. p. 44
Series
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1542
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-80211 (URN)LIU-TEK-LIC-2012:27 (Local ID)978-91-7519-843-9 (ISBN)LIU-TEK-LIC-2012:27 (Archive number)LIU-TEK-LIC-2012:27 (OAI)
Presentation
2012-09-07, Jordan/Fermi, Fysikhuset, Campus Valla, Linköpings universitet, Linköping, 10:15 (Swedish)
Opponent
Supervisors
Available from: 2012-08-22 Created: 2012-08-22 Last updated: 2016-08-31Bibliographically approved
Fager, H., Andersson, J. M., Mei, A., Howe, B., Greene, J. E., Petrov, I. & Hultman, L.Growth and Properties of Amorphous Hf1−x−yAlxSiyN (0≤x≤0.2; 0≤y≤0.2) and a-Hf0.6Al0.2Si0.2N/nc-HfN Multilayers by DC Reactive Magnetron Sputtering from a Single Hf0.60Al0.20Si0.20 Target.
Open this publication in new window or tab >>Growth and Properties of Amorphous Hf1−x−yAlxSiyN (0≤x≤0.2; 0≤y≤0.2) and a-Hf0.6Al0.2Si0.2N/nc-HfN Multilayers by DC Reactive Magnetron Sputtering from a Single Hf0.60Al0.20Si0.20 Target
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(English)Manuscript (preprint) (Other academic)
Abstract [en]

Amorphous (a) and nanocrystalline (nc) Hf1−x−yAlxSiyN and multilayer a-Hf0.6Al0.2Si0.2N/nc-HfN films are grown on Si(001) at temperatures Ts = 100-450 ◦C using ultrahigh vacuum magnetically-unbalanced reactive magnetron sputtering from a single Hf0.60Al0.20Si0.20 target in a 5%-N2/Ar atmosphere at a total pressure of 20 mTorr (2.67 Pa). The composition and nanostructure of Hf1−x−yAlxSiyN is controlled during growth by independently varying the ion energy (Ei) and the ion-to-metal flux ratio (Ji/JMe) incident at the film surface. With Ji/JMe = 8, the composition and nanostructure of the films ranges from x-ray amorphous with 1-x-y = 0.60 at Ei = 15 eV, to an amorphous matrix with encapsulated nanocrystals with 1-x-y = 0.66-0.84 at Ei = 25-35 eV, to nanocrystalline with 1-x-y = 0.96-1.00 at Ei = 45-65 eV. Varying Ji/JMe with Ei = 13 eV yields amorphous alloy films at Ts = 100 ◦C. a-Hf0.6Al0.6Si0.6N/nc-HfN multilayers with periods Λ = 2-20 nm exhibit enhanced fracture toughness compared to polycrystalline VN, TiN, and Ti0.5Al0.5N reference samples; multilayer hardness values increase monotonically from 20 GPa with Λ = 20 nm to 27 GPa with Λ = 2 nm.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-80207 (URN)
Available from: 2012-08-22 Created: 2012-08-22 Last updated: 2016-08-31Bibliographically approved
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