硅对铸态CoCrFeMnNi高熵合金组织及性能的影响

Effect of Si addition on microstructure and properties of as⁃cast CoCrFeMnNi high entropy alloy

采用冷坩埚悬浮熔炼法制备了CoCrFeMnNiSi_(x)(x=0,0.3,0.6,0.9)系列高熵合金。使用X射线衍射仪、扫描电镜及附带的能谱仪分析了硅添加后合金组织结构的变化,并对CoCrFeMnNiSi_(x)合金硬度、室温摩擦磨损及室温压缩性能进行了一系列测试。结果表明,CoCrFeMnNi合金为单相FCC结构,随着硅含量的增加,FCC基相晶界处Mn、Ni、Si元素富集并且逐渐析出硅化物,产生细晶强化及弥散强化,从而使合金的硬度、耐磨性、压缩强度和压缩屈服强度得到提升,其中,CoCrFeMnNiSi_(0.9)合金综合性能最佳。

CoCrFeMnNiSi_(x)(x=0,0.3,0.6,0.9)high entropy alloys were fabricated by cold crucible levitation melting.The changes of the microstructure of the alloy after the addition of silicon were analyzed by means of X⁃ray diffraction,scanning electron microscope and the attached energy spectrometer.A series of tests on the hardness,room temperature friction and wear and room temperature compression properties of CoCrFeMnNiSi_(x) alloy were carried out.The results show that CoCrFeMnNi alloy is a single⁃phase FCC structure.With the increase of silicon content,Mn,Ni and Si elements are enriched at the grain boundary of the FCC base phase,and silicide are gradually precipitated,finally resulting in fine grain strengthening and dispersion strengthening,which improves the hardness,wear resistance,compressive strength and yield strength of the alloy.Among them,CoCrFeMnNiSi_(0.9) has the best comprehensive performance.