TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy

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	TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy; TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy
	J. G. Wang; L. C. Zhang; G. L. Chen; H. Q. Ye
	1998 ; 1998
发表期刊	Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing ; Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing
ISSN	0921-5093 ; 0921-5093
卷号	252 期号:2 页码:222-231
摘要	Two types of {111} [11 (2) over bar] twins in a hot-deformed Ti-45Al-10Nb alloy were investigated by high resolution transmission electron microscopy (HREM). Type P ((111) [11 (2) over bar]) twins can be formed either through dislocation mechanisms or at grain boundary. The former can be further described by two mechanisms. One is the pole mechanism and the other is the dissociation of a perfect dislocation mechanism. For the formation of twins at the grain boundary, twins can be nucleated by bowing out of twinning dislocations at the grain boundary and propagated by the sequential emission of twinning dislocations on every adjacent twinning plane. 1/3[111] Frank partial dislocations can be observed at steps on the incoherent twin boundary of some twins. A mechanism has been proposed to illustrate the propagation of the twins with or without 1/3[111] Frank partials at the steps on the incoherent twin boundary. Type Q (((1) over bar 11)[(1) over bar 1 (2) over bar]) twins usually formed at the lamellar interfaces. The steps on these lamellar interfaces are the common sites for the nucleation of type Q twins. Deformation twinning in lamellar TiAl alloys was suggested as a stress relaxation process for the pile-up of interfacial dislocations. Possible dislocation mechanisms for the generation of twinning dislocations on the lamellar interface are discussed. (C) 1998 Elsevier Science S.A. All rights reserved.; Two types of {111} [11 (2) over bar] twins in a hot-deformed Ti-45Al-10Nb alloy were investigated by high resolution transmission electron microscopy (HREM). Type P ((111) [11 (2) over bar]) twins can be formed either through dislocation mechanisms or at grain boundary. The former can be further described by two mechanisms. One is the pole mechanism and the other is the dissociation of a perfect dislocation mechanism. For the formation of twins at the grain boundary, twins can be nucleated by bowing out of twinning dislocations at the grain boundary and propagated by the sequential emission of twinning dislocations on every adjacent twinning plane. 1/3[111] Frank partial dislocations can be observed at steps on the incoherent twin boundary of some twins. A mechanism has been proposed to illustrate the propagation of the twins with or without 1/3[111] Frank partials at the steps on the incoherent twin boundary. Type Q (((1) over bar 11)[(1) over bar 1 (2) over bar]) twins usually formed at the lamellar interfaces. The steps on these lamellar interfaces are the common sites for the nucleation of type Q twins. Deformation twinning in lamellar TiAl alloys was suggested as a stress relaxation process for the pile-up of interfacial dislocations. Possible dislocation mechanisms for the generation of twinning dislocations on the lamellar interface are discussed. (C) 1998 Elsevier Science S.A. All rights reserved.
部门归属	univ calif lawrence livermore natl lab, livermore, ca 94551 usa. univ sci & technol beijing, state key lab adv met & mat, beijing 100083, peoples r china. acad sinica, inst met res, atom imaging solids lab, shenyang 110015, peoples r china.;wang, jg (reprint author), univ calif lawrence livermore natl lab, pob 808,l-370, livermore, ca 94551 usa ; univ calif lawrence livermore natl lab, livermore, ca 94551 usa. univ sci & technol beijing, state key lab adv met & mat, beijing 100083, peoples r china. acad sinica, inst met res, atom imaging solids lab, shenyang 110015, peoples r china.;wang, jg (reprint author), univ calif lawrence livermore natl lab, pob 808,l-370, livermore, ca 94551 usa
关键词	Intermetallic Compounds Intermetallic Compounds Tial Alloys Tial Alloys Mechanical Twinning Mechanical Twinning Tem Tem Resolution Electron-microscopy Resolution Electron-microscopy Interfacial Boundaries Interfacial Boundaries Deformation Deformation Twins Twins Intersections Intersections Temperatures Temperatures Propagation Propagation Aluminides Aluminides Ti Ti
URL	查看原文 ; 查看原文
WOS记录号	WOS:000075629000009 ; WOS:000075629000009
引用统计	被引频次：21[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/321006/37800
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	J. G. Wang,L. C. Zhang,G. L. Chen,et al. TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy, TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy[J]. Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing,1998, 1998,252, 252(2):222-231, 222-231.
APA	J. G. Wang,L. C. Zhang,G. L. Chen,&H. Q. Ye.(1998).TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy.Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing,252(2),222-231.
MLA	J. G. Wang,et al."TEM observations of mechanical twins in a hot-deformed Ti-45Al-10Nb alloy".Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing 252.2(1998):222-231.