AlxFeCoNi2.05近共晶高熵合金组织和力学性能研究  

Research on Microstructure and Mechanical Properties of AlxFeCoNi2.05 Near-Eutectic High-Entropy Alloys

作　　者：张仰庆 要玉宏[1] 侯永昌 ZHANG Yangqing;YAO Yuhong;HOU Yongchang(School of Materials and Chemical Engineering,Xi’an Technological University,Xi’an 710021,China)

机构地区：[1]西安工业大学材料与化工学院

出　　处：《西安工业大学学报》2020年第1期88-94,共7页Journal of Xi’an Technological University

基　　金：国家自然基金（51571155）;陕西省教育厅重点实验室基金（17JS054）;陕西省自然科学基础研究计划项目（2017JM5057）

摘　　要：为研究Al元素含量对AlxFeCoNi 2.05(x=0.85,0.95,1.05)近共晶高熵合金组织和拉伸性能的影响,通过扫描电子显微镜(SEM)观察合金的显微组织和断口形貌,采用X射线衍射仪(XRD)和透射电子显微镜(TEM)研究Al原子含量对晶体结构的影响。试验结果表明:在该共晶系高熵合金中,Al元素为共晶形成元素。当Al元素含量为0.95时,合金具有由层片状L12相和B2相组成的完全共晶组织,其中富含Fe和Co元素的L12相为领先相,B2相富含Ni和Al元素。当Al元素含量为0.85时,合金组织为L12初生+(L12+B2)共晶组成的亚共晶组织;当Al元素含量为1.05时,合金组织为B2初生+(L12+B2)共晶组成的过共晶组织。正是由于显微组织的差异,AlxFeCoNi 2.05(x=0.85,0.95,1.05)合金的屈服强度由650 MPa降低到450 MPa和510 MPa,而延伸率由12%大幅度增加到29%和27.5%。The paper studies the effect of Al content on the microstructure and tensile properties of AlxFeCoNi2.05(x=0.85,0.95 and 1.05)near-eutectic high-entropy alloys,the microstructure and fracture morphology of the alloy were observed with a scanning electron microscopy(SEM),the crystal structure was analyzed with an X-ray diffractometer(XRD)and a transmission electron microscope(TEM).Results indicate that Al is an eutectic forming element in the AlxFeCoNi2.05 near-eutectic highentropy alloy.The AlxFeCoNi2.05 alloy with 0.95 Al has a completely eutectic structure composed of the leading lamellar L12 phase rich in Fe and Co and B2 phase rich in Ni and Al.The alloys with 0.85 and 1.05 Al respectively has a hypoeutectic structure of primary L12 phase+eutectic(L12+B2)phase and a hypereutectic structure of primary B2 phase + eutectic(L12+B2)phase.Because of difference microstructure,the yield strengths of AlxFeCoNi2.05(x=0.85,0.95,1.05)alloys reduce from 650 MPa to 450 MPa and 510 MPa,while their elongation increases significantly increase from 12%to 29% and 27.5%.

关 键 词：共晶高熵合金 初生相 B2相 L12相 显微组织 力学性能 

分 类 号：TG113[金属学及工艺—物理冶金]