Interactions between dislocations and twins in deformed titanium aluminide crystals. Issue 3 (March 2019)

• Record Type: Journal Article
• Authors: Yang, Guang; Ma, Shang-Yi; Du, Kui; Xu, Dong-Sheng; Chen, Sen; Qi, Yang; Ye, Heng-Qiang
• Is Part Of: Journal of materials science & technology. Volume 35:Issue 3(2019)
• Page Start: 402
• Page End: 408
• Publication Date: 2019-03
• Subjects: TiAl -- Dynamic deformation -- Twins -- Dislocations -- Abnormal stacking fault; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2018.09.031
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: Using scanning, transmission electron microscopy and aberration-corrected scanning transmission electron microscopy, we have studied the interactions between dislocations and twins in impact deformed polysynthetic twinned TiAl crystal. The 1/3 < 1 1 ¯ 1 ¯ ] and 1/6 < 211] step dislocations on coherent twin boundaries reveal the interactions of glissile 1/2 < 101> dislocations with the coherent twin boundaries. An abnormal stacking fault was found adjacent to the coherent twin boundary. It has the same stacking sequence but different atom species in the [ 1 ¯ 10] direction with an additional displacement of 1/4[ 1 ¯ 10] in two neighboring {111} layers, and is likely induced by the slip of a 1/12[112] (i.e. 1/4[ 1 ¯ 10] + 1/6[2 1 ¯ 1]) dislocation.