Microstructure and mechanical properties of ultra-fine grained MoNbTaTiV refractory high-entropy alloy fabricated by spark plasma sintering

作     者：Qing Liu Guofeng Wang Xiaochong Sui Yongkang Liu Xiao Li Jianlei Yang 

作者机构：National Key Laboratory for Precision Hot Processing of MetalsHarbin Institute of Technology 

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

年 卷 期：2019年第35卷第11期

页      面：2600-2607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 financially by the National Natural Science Foundation of China (No.51875122) 

主　　题：Refractory high-entropy alloy Ultra-fine grain Mechanical alloying Spark plasma sintering Mechanical properties 

摘      要：The MoNbTaTiV refractory high-entropy alloy(RHEA)with ultra-fine grains and homogeneous microstructure was successfully fabricated by mechanical alloying(MA)and spark plasma sintering(SPS).The microstructural evolutions,mechanical properties and strengthening mechanisms of the alloys were systematically *** nanocrystalline mechanically alloyed powders with simple bodycentered cubic(BCC)phase were obtained after 40 h MA ***,the powders were sintered using SPS in the temperature range from 1500℃to 1700℃.The bulk alloys were consisted of submicron scale BCC matrix and face-centered cubic(FCC)precipitation *** bulk alloy sintered at 1600℃had an average grain size of 0.58μm and an FCC precipitation phase of 0.18μm,exhibiting outstanding micro-hardness of 542 HV,compressive yield strength of 2208 MPa,fracture strength of 3238 MPa and acceptable plastic strain of 24.9%at room *** enhanced mechanical properties of the MoNbTaTiV RHEA fabricated by MA and SPS were mainly attributed to the grain boundary strengthening and the interstitial solid solution *** is expectable that the MA and SPS processes are the promising methods to synthesize ultra-fine grains and homogenous microstructural RHEA with excellent mechanical properties.