激光熔化沉积CrMnFeCoNi高熵合金组织和低温力学性能

采用激光熔化沉积和铸造技术分别制备了CrMnFeCoNi高熵合金。通过X射线衍射(XRD)、金相腐蚀、扫描电镜(SEM)和力学拉伸实验等分析手段对不同方法制备的CrMnFeCoNi高熵合金相组成、微观组织及力学性能进行了对比研究。结果表明:通过激光熔化沉积和铸造技术制备的CrMnFeCoNi高熵合金均为面心立方(FCC)单相固溶体结构;采用激光熔化沉积技术制备的CrMnFeCoNi高熵合金具有更为均匀的元素分布;随着温度从293 K降低到77 K,激光熔化沉积技术制备的CrMnFeCoNi高熵合金的拉伸强度与塑性分别从518 MPa、55%提升到878 MPa、95%,表现出优异的低温力学性能。

Microstructure and low temperature mechanical properties of CrMnFeCoNi high-entropy alloys deposited by laser melting

CrMnFeCoNi high-entropy alloys were prepared by laser melting deposition(LMD)and casting,respectively.The phase composition,microstructure and mechanical properties of the CrMnFeCoNi high-entropy alloys were studied by means of X-ray diffraction(XRD),metallographic corrosion,scanning electron microscopy(SEM)and mechanical tensile test.The results show that the CrMnFeCoNi high entropy alloys prepared by laser melting deposition and casting technology are face centered cubic(FCC)single phase solid solution structure,and the CrMnFeCoNi high entropy alloys prepared by laser melting deposition have more uniform element distribution.With the decrease of temperature from 293 K to 77 K,the tensile strength and plasticity of the CrMnFeCoNi high entropy alloys prepared by laser melting deposition increase from 518 MPa and 55%to 878 MPa and 95%,respectively,showing excellent mechanical properties at low temperature.