Glide mechanism of ordinary dislocations in the γ phase of TiAl

被引：17
作者：
Couret, A [1 ]
机构：
[1] CNRS, CEMES, F-31055 Toulouse 4, France
来源：
INTERMETALLICS | 2001年 / 9卷 / 10-11期
关键词：
titanium aluminides; based on TiAl; plastic deformation mechanisms; defects : dislocation geometry; arrangement; electron microscopy; transmission;
D O I：
10.1016/S0966-9795(01)00088-7
中图分类号：
O64 [物理化学（理论化学）、化学物理学];
学科分类号：
070304 ; 081704 ;
摘要：
Glide mechanism of ordinary dislocations in the gamma phase of TiAl alloys is studied by in situ straining experiments. A polar source and several dynamic sequences showing moving dislocations are presented. It is shown that the deformation is due to rectilinear screw dislocations anchored at many pinning points. The origin of the frictional force opposing to the dislocation movements and that of these pinning points are analysed and discussed. Experimental observations show also that an increase of temperature leads to a fast deformation by bursts of dislocations. This temperature effect is interpreted by dynamic strain ageing. (C) 2001 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码：899 / 906
页数：8
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