Effect of Heat Treatment on the Microstructure of Multiphase NiAl-based Alloy

作     者：Yi XIE Lanzhang ZHOU Jianting GUO Hengqiang YE 

作者机构：Superalloys Division Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Shenyang National Laboratory for Materials Science 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：2008年第24卷第2期

页      面：245-250页

核心收录：

学科分类：0817[工学-化学工程与技术] 08[工学] 

主　　题：NiAl Intermetallics Microstructure Solution and aging treatments 

摘      要：The alloy Ni-Al26.6-Cr13.4-Co8.1-Ti4.3-W1.3-Mo0.9 （at. pct） was fabricated from superalloy K44 and Al element using vacuum induction and casting technique. Investigations to this alloy reveal that a new phase Cr3Ni2 possessing low melting point and poor ductility is formed, which is distributed as a network along NiAI matrix grain boundaries. Subsequent different solution and aging treatments are carried out and lead to microstructural changes to various extents. Rapid cooling after solution at 1250℃ for 20 h gives rise to macrocracks in the specimen while slow cooling after the same treatment results in the formation of spheric α-Cr solid solution and needle-like Ni3Al phase, which are embedded in NiAl matrix. It is comfirmed that aging treatments initiate lath-shaped Ni3Al phase and pearl-shaped α-Cr phase to precipitate from the NiAl matrix, which own orientation relationships with these precipitates.