真空热压烧结制备CuCrFeMnNi高熵合金的退火软化行为

Annealing Softening Behavior of CuCrFeMnNi High-entropy Alloy via Vacuum HotpressingSintering

采用真空热压烧结工艺制备了CuCrFeMnNi高熵合金,对其进行(600~900℃)×12h的退火处理,通过显微硬度测试、物相分析和微观组织观察等研究了退火温度对合金组织结构以及显微硬度的影响。结果表明,CuCrFeMnNi高熵合金的烧结态硬度(HV)约为543,随退火温度升高,合金显微硬度逐渐降低。当退火温度为900℃时,CuCrFeMnNi高熵合金的显微硬度(HV)降至268,约是烧结态的52%,表明该合金经高温退火处理后发生了显著的退火软化现象。XRD结果表明,CuCrFeMnNi高熵合金由烧结态的FCC主相(FCC1+FCC2)+ρ相的多相结构转变为FCC2相的单相结构。因此,该合金退火软化主要归因于ρ相的分解。

CuCrFeMnNi high-entropy alloy was fabricated using vacuum hot pressing sintering process,and annealed at 600~900℃for 12 h.The effects of annealing temperature on microstructure and microhardness of alloy were investi⁃gated by microhardness testing,phase analysis and microstructure observation.The results reveal that the sintered hardness of CuCrFeMnNi high-entropy alloy is around 543 HV,which is gradually decreased with the increase of annealing temperature.With annealing temperature of 900℃,the microhardness is decreased to 268 HV,which is about 52%times of the sintered one,indicating that the alloy undergoes significant annealing softening after hightemperature annealing treatment.XRD patterns demonstrate that the CuCrFeMnNi high-entropy alloy is transformed from a multiphase structure of sintered FCC main phase(FCC1+FCC2)+ρphase to a single-phase structure of FCC2 phase.Therefore,the annealing softening is mainly attributed to the decomposition ofρphase.