Structural stability and the alloying effect of TiB polymorphs in TiAl alloys

IMR OpenIR

	Structural stability and the alloying effect of TiB polymorphs in TiAl alloys
	Liu, B. G.; Liu, L. H.; Xing, W. D.; Liu, R. C.; Yang, R.; Withey, P. A.; Zhu, J.; Yu, R.; Yu, R (reprint author), Tsinghua Univ, Sch Mat Sci & Engn, Natl Ctr Electron Microscopy Beijing, Beijing 100084, Peoples R China.
	2017-11-01
发表期刊	ELSEVIER SCI LTD
ISSN	0966-9795
卷号	90 页码:97-102
摘要	Borides have been widely used in cast TiAl alloy for grain refinement and a variety of stoichiometry and crystal structure of borides were reported. Here the effects of alloying elements Nb, Ta, and Mn on the structural stability of fine boride precipitates in TiAl alloys have been studied combining transmission electron microscopy (TEM) and first-principles calculations. The results show that most boride particles have the TiB stoichiometry. In the alloy containing Nb and Mn, all the TiB particles have the B27 structure and are highly enriched with Nb but depleted with Mn. In the alloy containing Nb and Ta, however, the intergrowth of B-f and B27 structure has been observed, and the TiB particles are enriched with both Nb and Ta. First-principles calculations reveal different effects of Nb, Ta, and Mn on the structural stability of TiB polymorphs. Nb stabilizes B27 but destabilizes B-f. Ta strongly stabilizes both B27 and B-f structures. Mn strongly destabilizes both B27 and B-f structures.; Borides have been widely used in cast TiAl alloy for grain refinement and a variety of stoichiometry and crystal structure of borides were reported. Here the effects of alloying elements Nb, Ta, and Mn on the structural stability of fine boride precipitates in TiAl alloys have been studied combining transmission electron microscopy (TEM) and first-principles calculations. The results show that most boride particles have the TiB stoichiometry. In the alloy containing Nb and Mn, all the TiB particles have the B27 structure and are highly enriched with Nb but depleted with Mn. In the alloy containing Nb and Ta, however, the intergrowth of B-f and B27 structure has been observed, and the TiB particles are enriched with both Nb and Ta. First-principles calculations reveal different effects of Nb, Ta, and Mn on the structural stability of TiB polymorphs. Nb stabilizes B27 but destabilizes B-f. Ta strongly stabilizes both B27 and B-f structures. Mn strongly destabilizes both B27 and B-f structures.
部门归属	[liu, b. g. ; liu, l. h. ; xing, w. d. ; zhu, j. ; yu, r.] tsinghua univ, sch mat sci & engn, natl ctr electron microscopy beijing, beijing 100084, peoples r china ; [liu, b. g. ; liu, l. h. ; xing, w. d. ; zhu, j. ; yu, r.] tsinghua univ, sch mat sci & engn, key lab adv mat, minist educ china, beijing 100084, peoples r china ; [liu, b. g. ; liu, l. h. ; xing, w. d. ; zhu, j. ; yu, r.] tsinghua univ, sch mat sci & engn, state key lab new ceram & fine proc, beijing 100084, peoples r china ; [liu, r. c. ; yang, r.] chinese acad sci, inst met res, shenyang 110016, liaoning, peoples r china ; [withey, p. a.] rolls royce plc, derby de24 8bj, england
关键词	Titanium Aluminides Borides Structural Stability Transmission Electron Microscopy First-principles Calculations
学科领域	Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
资助者	NSFC [51525102, 51390475, 51371102]; National Basic Research Program of China [2015CB654902]
收录类别	SCI
语种	英语
WOS记录号	WOS:000411547100014
引用统计	被引频次：37[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/79022
专题	中国科学院金属研究所
通讯作者	Yu, R (reprint author), Tsinghua Univ, Sch Mat Sci & Engn, Natl Ctr Electron Microscopy Beijing, Beijing 100084, Peoples R China.
推荐引用方式 GB/T 7714	Liu, B. G.,Liu, L. H.,Xing, W. D.,et al. Structural stability and the alloying effect of TiB polymorphs in TiAl alloys[J]. ELSEVIER SCI LTD,2017,90:97-102.
APA	Liu, B. G..,Liu, L. H..,Xing, W. D..,Liu, R. C..,Yang, R..,...&Yu, R .(2017).Structural stability and the alloying effect of TiB polymorphs in TiAl alloys.ELSEVIER SCI LTD,90,97-102.
MLA	Liu, B. G.,et al."Structural stability and the alloying effect of TiB polymorphs in TiAl alloys".ELSEVIER SCI LTD 90(2017):97-102.