A high-Nb-TiAl alloy with ultrafine-grained structure fabricated by cryomilling and spark plasma sintering  

作　　者：Hao Deng Yong-Qiang Wei Jun Tang Ai-Jun Chen Long-Qing Chen Zu-Xi Xia 

机构地区：[1]Key Laboratory of Radiation Physics and Technology of Ministry of Education,Institute of Nuclear Science and Technology,Sichuan University,Chengdu,610064,China [2]The Second Research Institute of Civil Aviation Administration of China(CAAC),Chengdu,610064,China

出　　处：《Rare Metals》2023年第5期1678-1685,共8页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.11475118)。

摘　　要：In this work,an ultrafine-grained high-Nb-TiAl alloy with a nominal composition of Ti-45Al-8Nb-0.2W-0.2B(at%)was prepared by cryomilling and subsequent spark plasma sintering(SPS)technique.The chemical composition,particle size,morphology and crystallite size of cryomilled powder were studied.It is found that cryomilling can effectively reduce the particle size and enhance grain refinement.The ingots sintered at 900 and 1000℃ show an equiaxed near-γmicrostructure with grain sizes<700 nm,while the sample sintered at 1100℃exhibits duplex microstructure.Especially,the one sintered at 1000℃ has excellent mechanical properties,whose compression yield strength,fracture strength,bending strength and plastic strain achieve 1310,2174,578 MPa and 16.8%,respectively.The reasons for the effect of cryomilling and the mechanical behavior of sintered ingots were discussed.It is suggested that cryomilling in combination with SPS is an effective way to synthesize high-NbTiAl alloy with ultrafine-grained structure.

关 键 词：CRYOMILLING Spark plasma sintering Titanium aluminide Ultrafine-grained structure 

分 类 号：TG146.23[一般工业技术—材料科学与工程]