Microstructural refinement and enhanced mechanical properties of suction-cast NiTi-Al alloy for structural use  

作　　者：Li-Jing Zheng Ling Guo Fang-Fang Wang Ming-Zhen Ma Hu Zhang 

机构地区：[1]Key Laboratory of Aerospace Advanced Materials and Performance of Ministry of Education,School of Materials Science and Engineering,Beihang University,Beijing,100191,China [2]School of Materials Science and Engineering,Yanshan University,Qinhuangdao,066004,China

出　　处：《Rare Metals》2022年第8期2739-2744,共6页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos.51101003 and 51471012)

摘　　要：A significant refinement of the microstructure of structural NiTi alloy was achieved through a combination of Al addition and fabrication by suction casting.This is attributed to the change from a layer-by-layer to volume solidification mode with Al content increasing,which causes a change in grain shape from columnar to equiaxed.Furthermore,when compared with conventional casting,suction casting optimizes the microstructure of the alloy by refining the grain size and ensuring a homogeneous distribution of Ti2 Ni and Ni_(2)TiAl phases.The high cooling rate of suction casting also delays the formation ofβ'-Ni_(2)TiAl phase.Finally,this fine microstructure and uniform distribution of intermetallic phases result in the ultimate compressive strength of up to 2463.7 MPa,representing an improvement of 370 MPa over conventionally cast NiTi-Al alloy.

关 键 词：NiTi-Al intermetallic compound Suction casting Microstructure Compressive strength 

分 类 号：TG146.15[一般工业技术—材料科学与工程]