Cr对FeCoNiAlCr_(x)高熵合金组织与力学性能的影响  

Effect of Cr on microstructure and mechanical properties of FeCoNiAlCr_(x) high entropy alloys

作　　者：高炜 余竹焕[1] 阎亚雯 王晓慧 刘旭亮 杜伟 GAO Wei;YU Zhuhuan;YAN Yawen;WANG Xiaohui;LIU Xuliang;DU Wei(College of Materials Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学材料科学与工程学院,西安710054

出　　处：《材料工程》2023年第2期91-97,共7页Journal of Materials Engineering

基　　金：西安科技大学优秀青年科技基金项目(2018YQ2-12);凝固技术国家重点实验室开放课题(SKLSP201846);陕西省留学人员科技活动择优资助项目(2018047)。

摘　　要：采用真空电弧熔炼法制备FeCoNiAlCr_(x)(x=0,0.2,0.4,0.6,0.8,原子比,下同)高熵合金铸锭,探究Cr含量对该合金微观结构、组织及力学性能的影响。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱仪(EDS)对合金相结构、微观组织及成分进行分析表征;采用万能试验机对合金压缩性能进行测试。结果表明:随着Cr含量的增加,合金的微观结构由单相BCC结构转变为BCC+FCC混合结构;合金微观组织由等轴晶逐步转变为树枝晶,并且合金晶粒尺寸发生了明显细化。本实验制备的五种合金都具有较好的力学性能,合金的抗压强度随着Cr含量的增加大幅度增强,当x=0时合金抗压强度和塑性应变最低,分别为1500 MPa和13.56%;当x=0.8时,合金抗压强度和塑性应变达到最大,分别为2460 MPa和30.09%;合金抗压强度的增幅达64%。这表明Cr添加对FeCoNiAlCr_(x)高熵合金的组织细化、抗压强度和塑性的提升具有重要作用。FeCoNiAlCr_(x)(x=0,0.2,0.4,0.6,0.8,atomic ratio)high-entropy alloy ingots were prepared by vacuum arc melting method,and the effect of Cr content on the microstructure and mechanical properties of the alloy was investigated.The phase structure,microstructure and the composition of the alloy were analyzed and characterized by X-ray diffractometer(XRD),scanning electron microscope(SEM)and energy dispersive spectrometer(EDS).The compression properties of the alloy were tested by universal testing machine.The results show that with the increase of Cr content,the microstructure of the alloy changes from a single-phase BCC structure to a BCC+FCC mixed structure;the microstructure of the alloy gradually changes from an equiaxed structure to a dendrite structure,and the grain size of the alloy is obviously refined.The five alloys prepared in this experiment have relatively good mechanical properties,and the compressive strength of the alloy increases greatly with the increase of Cr content.When x=0,the compressive strength and plastic strain of the alloy are the lowest,which are 1500 MPa and 13.56%,respectively;when x=0.8,the compressive strength and plastic strain of the alloy reach the maximum,which are 2460 MPa and 30.09%,respectively;the compressive strength of the alloy increases by 64%.It indicates that Cr addition plays an important role in the microstructure refinement,the improvement of compressive strength and ductility of FeCoNiAlCr_(x) high-entropy alloys.

关 键 词：高熵合金 相结构 显微组织 力学性能 断口形貌 压缩性能 

分 类 号：TG139[一般工业技术—材料科学与工程]