Effect of Orientation on Stress-Rupture Property and Related Deformation Microstructure of a Ni-Base Re-containing Single-Crystal Superalloy at 900℃

• 作者: Guang-Lei Wang Jin-Lai Liu Ji-De Liu Yi-Zhou Zhou Xu-Dong Sun Hai-Feng Zhang Xiao-Feng Sun
• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2021,（5）
• 页码范围: 719-728
• 页数: 10页
• 语种: 英文

摘要

Stress-rupture properties of a Ni-base Re-containing single-crystal superalloy with three orientations have been tested under 900℃/445 MPa.An obvious anisotropy of stress-rupture property is attributed to orientation reliant deformation micro-structure.The good strength in[001]orientation is attributed to the rapid multiplication of dislocations active in horizontal channels and later γ' cutting via dislocations pair coupled with anti-phase boundary.The microtwin formation largely limits the strength and plasticity as a result of the continuous shearing across γ/γ' microstructure by{111}〈112〉slip activated in[011]orientation.The property in[111]orientation results mainly from the lateral cross-slip movements of the screw disloca-tions within connected matrix channels as well as the precipitate shearing by coplanar dislocations.Microcracks all initially originate from the interdendritic micropores in three orientations.The critical temperature of stress-rupture anisotropy could be increased by a high level of refractory solutes especially Re.