Mn对CoCrFeNi基高熵合金组织及性能的影响

Effects of Mn on Microstructure and Properties of CoCrFeNi Based High Entropy Alloys

研究了不同的Mn掺入量对CoCrFeNi基高熵合金相组成、凝固组织以及宏观性能的影响。结果表明:CoCrFeNiMnx(x=0.25,0.5,1,2)合金的液相线温度分别为1736、1639、1692、1638 K,且升温过程均发生了一次相变;确定了这四种成分的合金均为单相FCC固溶体合金,且Fe、Co、Cr三种元素富集于主晶面,Mn、Ni两种元素富集于晶界处。随着溶质Mn含量的增多,CoCrFeNiMnx合金的电阻率会变大,CoCrFeNiMn2合金的电阻率最大,达到了210.215μΩ/cm。随着Mn含量的增多,CoCrFeNiMnx高熵合金的屈服强度先增大后减小,其中CoCrFeNiMn合金的屈服强度最大,达319.6 MPa。

The effects of different Mn doping content on the phase composition, solidification structure and macroscopic properties of CoCrFeNi based high entropy alloys were investigated. The results show that the liquid temperature of CoCrFeNiMnx(x =0.25,0.5,1,2) alloys is 1736 K, 1639 K, 1692 K, 1638 K, respectively, and a phase change occurs in the heating process. It is determined that these four high entropy alloys are single-phase solid solution alloys, and the elements of Fe,Co,Cr are concentrated in the main crystal plane, and Mn,Ni elements are enriched in the grain boundaries. The resistivity of CoCrFeNiMnxalloy increases with the increase of Mn content, and the resistivity of CoCrFeNiMn2 alloy is largest, reaching210.215 μΩ/cm. With the increase of Mn content, the yield strength of CoCrFeNiMnxhigh-entropy alloy increases first and then decreases. The yield strength of CoCrFeNiMn alloy is largest, reaching 319.6 MPa.