First-principles investigations of omega variant selection during athermal beta -> omega transformation of binary Ti-xMo alloy

doi:10.1016/j.commatsci.2018.09.028

CORC > 金属研究所 > 中国科学院金属研究所

	First-principles investigations of omega variant selection during athermal beta -> omega transformation of binary Ti-xMo alloy
	Zhu, JL ; Cao, S 2; Wang, YZ ; Yang, R ; Hu, QM
刊名	COMPUTATIONAL MATERIALS SCIENCE
	2018-12-01
卷号	155 页码:524-533
关键词	Titanium alloys Phase transformation Variant selection First-principles calculation
ISSN号	0927-0256
DOI	10.1016/j.commatsci.2018.09.028
英文摘要	Variant selection during solid-solid phase transformation in titanium alloys affects greatly the microstructure and mechanical properties of the alloys. Theoretical investigations of the variant selection were generally performed by using phase field simulation that considers solely the elastic coherency strain energy. In the present work, we develop a model to determine the variant selection directly from first-principles calculations. The source of the variant selection is considered to be the varying free energy gains (including both bulk and interface contributions) induced by the transformation from the parent phase to different variants of the product phase. This model is applied to investigate the effects of shear stress and alloy composition on omega variant selection during athermal beta -> omega transformation in binary Ti-xMo (x <= 25 at. %) alloys. The random distribution of the atoms in the alloy is described by using virtual crystal approximation (VCA). We show that the tendency of variant selection becomes stronger with increasing shear stress. With increasing Mo concentration, the favorable omega variant transfers from one to another, except for the w phase with very small particle size (e.g., radius R <= 1 nm) where one variant is always selected. The critical Mo concentration for the transfer of the favorable omega variant approaches to 5 at.% with increasing size of the omega phase particles and remains almost unchanged against the shear stress. At the critical Mo concentration, the considered variants have equal free energy gains and there is no variant selection. This finding opens the possibility of controlling the variant selection and the associated microstructure by changing the composition of the alloys.
学科主题	Materials Science, Multidisciplinary
语种	英语
WOS记录号	WOS:000447748900059
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/79796]
专题	金属研究所_中国科学院金属研究所
作者单位	1.Chinese Acad Sci, Inst Met Res, 72 Wenhua Rd, Shenyang 110016, Liaoning, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Jinzhai Rd 96, Hefei 230026, Anhui, Peoples R China 3.Univ Chinese Acad Sci, Yuquan Rd 19, Beijing 100049, Peoples R China 4.Ohio State Univ, Dept Mat Sci & Engn, 2041 Coll Rd, Columbus, OH 43210 USA 5.Xi An Jiao Tong Univ, Frontier Inst Sci & Technol, Ctr Microstruct Sci, State Key Lab Mech Behav Mat, Xian 710049, Shaanxi, Peoples R China
推荐引用方式 GB/T 7714	Zhu, JL,Cao, S,Wang, YZ,et al. First-principles investigations of omega variant selection during athermal beta -> omega transformation of binary Ti-xMo alloy[J]. COMPUTATIONAL MATERIALS SCIENCE,2018,155:524-533.
APA	Zhu, JL,Cao, S,Wang, YZ,Yang, R,&Hu, QM.(2018).First-principles investigations of omega variant selection during athermal beta -> omega transformation of binary Ti-xMo alloy.COMPUTATIONAL MATERIALS SCIENCE,155,524-533.
MLA	Zhu, JL,et al."First-principles investigations of omega variant selection during athermal beta -> omega transformation of binary Ti-xMo alloy".COMPUTATIONAL MATERIALS SCIENCE 155(2018):524-533.