热处理对Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)高熵合金显微组织和硬度的影响  

Effect of heat treatment on microstructure and hardness of Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)high entropy alloy

作　　者：白莉[1] 刘蒙恩[1] 王方丽 彭莉[1] Bai Li;Liu Meng'en;Wang Fangli;Peng Li(Chongqing Industry Polytechnic College,Chongqing 401120,China)

机构地区：[1]重庆工业职业技术学院,重庆401120

出　　处：《金属热处理》2025年第4期34-39,共6页Heat Treatment of Metals

基　　金：重庆市教育委员会科学技术研究计划一般项目(KJQN202203227)。

摘　　要：通过真空电弧熔炼制备了Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)高熵合金,并对其进行了1200℃×2 h固溶和600℃×4 h时效处理。利用X射线衍射仪、扫描电镜、透射电镜和显微硬度计对高熵合金的微观组织结构和硬度进行了测试。结果表明,Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)高熵合金铸态组织为树枝晶,晶内为FCC相,枝晶间为BCC相,且在BCC相区均匀分布大量的B2相纳米粒子。在1200℃固溶2 h后,高熵合金组织由树枝晶转变为等轴晶,晶内为有序的B2相,仅在晶界处存在少量的FCC相。继续在600℃时效4 h后,B2相向FCC相转变导致高熵合金中B2相体积分数减小,并且在B2相区内析出α-Mn结构的椭球状纳米粒子。大量B2相以及α-Mn结构的椭球状纳米粒子的出现分别提高了Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)高熵合金固溶态和时效态的硬度,分别为419和517 HV0.5,相较于铸态硬度分别提高了51%和86%。Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)high entropy alloy was prepared by vacuum arc-melting method,followed by solution treatment at 1200℃for 2 h and aging at 600℃for 4 h.XRD,SEM,TEM and Vickers hardness tester were used to detect the microstructure and hardness of the high entropy alloy.The results show that the microstructure of the as-cast Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)high entropy alloy exhibits dendrite.The dendrite regions are FCC phase,while the interdendrite regions are BCC phase,in which a large number of B2 nanoparticles are uniformly exist.After solution treatment at 1200℃for 2 h,the microstructure of the high entropy alloy transforms from dendrite to equiaxed grains where the intragranular orderd B2 phase is,and only a small amount of FCC phase exists at the grain boundaries.After sequential aging at 600℃for 4 h,the B2 phase transform into FCC phase,resulting in the decrease of the volume fraction of B2 phase.Besides,the elliptic nanoparticles withα-Mn structure are precipitated in the B2 region.The appearance of B2 phase and the elliptic nanoparticles withα-Mn structure increase the hardness of the Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)high entropy alloy in solution treated and aged states,respectively,which are 419 and 517 HV0.5,51%and 86%higher than that of the as-cast Fe_(35)Mn_(35)Ni_(10)Cr_(10)Al_(10)high entropy alloy,respectively.

关 键 词：高熵合金 热处理 微观组织 B2相 α-Mn结构相 维氏硬度 

分 类 号：TG113[金属学及工艺—物理冶金]