Effects of decomposition route and microstructure on h-AlN formation rate in TiCrAlN alloys
2017 (English)In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 691, 1024-1032 p.Article in journal (Refereed) Published
The phase evolution of cubic (c), solid solution TixCr-0.37Al1-0.37-x N alloys with x = 0.03 and 0.16, and the kinetics of the hexagonal (h)-AlN formation are studied via in situ wide angle x-ray scattering experiments during high temperature (1000-1150 degrees C) annealing. Spinodal decomposition was observed in Ti0.16Cr0.36Al0.48N while Ti0.03Cr0.38Al0.59N decomposes through nucleation and growth of h-AlN, c-TiN and c-CrAlN. h-AlN is formed from c-CrAlN domains in both cases and the formation rate of h-AlN depends on the stability of the c-CrAlN domains. In Ti0.16Cr0.36Al0.48N, the c-CrAlN domains are stabilized by crystallographic coherency with the surrounding c-TiCrN in a microstructure originating from spinodal decomposition. This results in lower formation rates of h-AlN for this composition. These differences are reflected in higher activation energy for h-AlN formation in Ti0.16Cr0.36Al0.48N compared to Ti0.03Cr0.38Al0.59N. It also points out different stabilities of the intermediate phase c-CrAlN during phase decomposition of TiCrAlN alloys. Additional contributions to the low activation energy for formation of h-AlN in Ti0.03Cr0.38Al0.59N stems from precipitation at grain boundaries. (C) 2016 Elsevier B.V. All rights reserved.
Place, publisher, year, edition, pages
ELSEVIER SCIENCE SA , 2017. Vol. 691, 1024-1032 p.
Coating materials; Phase transitions; Kinetics; Synchrotron radiation
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:liu:diva-132647DOI: 10.1016/j.jallcom.2016.08.299ISI: 000386227900124OAI: oai:DiVA.org:liu-132647DiVA: diva2:1048400
Funding Agencies|EUs Erasmus-Mundus graduate school in Material Science and Engineering (DocMASE); Swedish Research Council VR [621- 2012-4401]; Rontgen-Angstrom Cluster grant [VR 2011-6505]; Swedish Foundation for Strategic Research, SSF [RMA08-0069]; Swedish government strategic research area grant AFM - SFO MatLiU [2009-00971]; VINNOVA (M - Era.net project) [2013-02355]2016-11-212016-11-182016-11-21