Microstructure and Elevated Temperature Tensile Behavior of Directionally Solidified Ni-rich NiAl-Mo(Hf) Alloy

作     者：Ping Han Yihui Qi Jianting Guo 

作者机构：Department of Physics Bohai University Jinzhou 121013 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2011年第27卷第5期

页      面：437-442页

核心收录：

学科分类：0817[工学-化学工程与技术] 0806[工学-冶金工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the Dr.Start Fund of Liaoning Science and Technology Agency(No. 20021071) the Program of the Innovation Team of Liaoning Office of Education (No. 2006T078) 

主　　题：NiA1 alloy Directional solidification Superplasticity Creep 

摘      要：The microstructure, high strain rate superplasticity and tensile creep behavior of directionally solidified （DS） NiAI-Mo（Hf） alloy have been investigated. The alloy exhibits dendritic structure, where dendritic arm is NiAI phase, interdendritic region is Ni3AI phase, and Mo-rich phase distributes in the NiAI and Ni3AI phases. The alloy exhibits high strain rate superplastic deformation behavior, and the maximum elongation is 104.2% at 1373 K and strain rate of 1.04xi0-2 s-I. The balance between strain hardening （by dislocation glide） and strain softening （by dynamic recovery and recrystallization） is responsible for the superplastic deformation. All the creep curves of the DS NiAI-Mo（Hf） alloy have similar shape of a short primary creep and dominant steady creep stages, and the creep strain is great. The possible creep deformation mechanism was also discussed. The creep fracture data follow the Monkman-Grant relationship.