标题
作者
作者:Liu, HW (Liu, H. W.)[1 ]; Xian, MF (Xian, M. F.)[1 ]; Huang, JY (Huang, J. Y.)[1 ]; Su, GC (Su, G. C.)[1 ]; Liu, JW (Liu, J. W.)[2,3,4 ]; Ouyang, LZ (Ouyang, L. Z.)[2,3,4 ]
期刊信息
摘要
Based on TiAl alloys bearing high levels of Nb, which are prospective high-temperature intermetallics, a new dual-phase alloy (Ti-40Al-10Fe (at%)) with precipitate growth direction close to the slipping plane normal of the matrix was developed. Transmission electron microscopy revealed that the annealed alloy was composed of equiaxed grains of tau(2)-TiAl2Fe and gamma-TiAl phases. Aging treatment at 1000 degrees C produced polygon-shaped gamma-TiAl precipitate from the tau(2)-TiAl2Fe matrix. The precipitation reaction of the face-centered cubic structure of tau(2)-TiAl2Fe into the ordered face-centered tetragonal structure of gamma-TiAl phase was systematically investigated in terms of crystallographic features, including mutual orientation relationship, growth direction, habit plane, side facets, and interfacial dislocation structure. The observed growth direction < 973 > was close to the normal of the slip plane {111}, with a discrepancy angle of similar to 20 degrees. Thus, the observed two-phase microstructure might significantly improve strengthening. It could also be quantitatively controlled by selection of precipitate and matrix with phase structures and lattice parameters that meet a certain requirement. (c) 2015 Elsevier Ltd. All rights reserved.
关键词
作者关键词:intermetallics (titanium aluminides); phase transformation (crystallographic aspects kinetics and mechanisms); heat treatment; microstructure; electron microscopy, transmission
作者信息
通讯作者地址:Liu, HW (通讯作者)
 | Guangxi Univ, Sch Mat Sci & Engn, Nanning 530004, Peoples R China. |
地址:
出版商
类别分类
研究方向:Chemistry; Materials Science; Metallurgy & Metallurgical Engineering
Web of Science 类别:Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering