Lamellar orientation control in TiAl base alloys by a two-step compression process at high temperature
Lamellar orientation control in TiAl base alloys by a two-step compression process at high temperature
复制标题
DOI：
10.1016/j.msea.2008.12.027
复制
发表时间：
2009-05
期刊：
影响因子：
6.4
通讯作者：
M. Hasegawa;H. Fukutomi
中科院分区：
文献类型：
--
作者：
M. Hasegawa;H. Fukutomi
为了实现全层TiAl基合金片层的有序排列，在α单相区和（α+γ）两相区进行了高温压缩。在α单相区进行压缩，观察到动态再结晶（DRX）的发生和纤维织构的形成。压缩轴的最大极密度在远离[公式：见正文]平面法线约35°的方向上。织构随真应变速率的降低而发展。这是因为在低Zener-Hollomon参数变形条件下，DRX主要通过应变诱导晶界迁移机制进行。在（α+γ）两相区压缩时，通过压缩观察到软化现象。这可归因于几何软化和动态再结晶的发生。在（α+γ）两相区压缩后，片层界面几乎平行于压缩面。
In order to arrange the lamellar plates of a fully lamellar TiAl base alloy, high temperature compression in the α single-phase region and (α+γ) two-phase region was applied. The occurrence of dynamic recrystallization (DRX) and the formation of fiber texture were observed by compression in the α single-phase region. The maximum pole density of the compression axis was in a direction about 35° away from the [Formula: see text] plane normal. Texture developed with decreasing true strain rate. This is because DRX proceeds mainly through a strain-induced grain boundary migration mechanism at low Zener–Hollomon parameter deformation conditions. Under compression in the (α+γ) two-phase region, softening was observed through compression. This can be attributed to the occurrence of geometrical softening and DRX. The lamellar interface became almost parallel to the compression plane after compression in the (α+γ) two-phase region.