Cr_xCuFe_2Mo_(0.5)Nb_(0.5)Ni_2高熵合金的微观组织与力学性能

Microstructure and Mechanical Properties of Cr_xCuFe_2Mo_(0.5)Nb_(0.5)Ni_2 High Entropy Alloys

采用电弧熔炼工艺制备了CrxCuFe2Mo0.5Nb0.5Ni2(x=0,0.5,1.0,2.0,摩尔比)高熵合金,采用X射线衍射分析(XRD)、扫描电镜(SEM)和显微硬度计对合金的物相结构、微观组织形貌、元素分布和硬度进行了分析。结果表明,合金物相主要由面心立方固溶体相(FCC)、体心立方固溶体相(BCC)和密排六方固溶体相(HCP)组成。Cr含量的增加,有利于BCC相的形成。合金组织主要呈树枝晶和枝晶间结构组成。合金中Nb、Mo和Cu元素分别偏聚于枝晶和枝晶间区域,Fe、Cr和Ni元素的分布相对均匀。合金硬度随Cr含量的增加而逐渐增加,但增幅较小。

The CrxCuFe2Mo0.5Nb0.5Ni2（x=0,0.5,1.0,2.0,mol）high entropy alloys were prepared by arc melting process.The phase,microstructure,element distribution and hardness of the alloys were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）and digital display Vickers hardness tester.The results show that the alloys are composed of a mixed structure of FCC,BCC and HCP solid solutions.The increase of Cr content is beneficial for the formation of BCC phase.The microstructure of the alloys is mainly characterized by a dendrite and interdendrite structure.The Nb,Mo and Cu are mostly segregated in dendrite and interdendrite regions,respectively,while the Fe,Cr,and Ni are homogeneously distributed in the alloys.The hardness has a slight increase with the increase of Cr content.