退火对AlCrFeCoNiCu高熵合金组织与性能的影响

Effect of Annealing on Microstructure and Properties of AlCrFeCoNiCu High-Entropy Alloy

利用真空电弧炉制备了AlCrFeCoNiCu高熵合金,研究了铸态与退火态合金的组织与性能。结果表明:合金的铸态组织是树枝晶,由具有面心立方(FCC)结构和体心立方(BCC)结构的固溶体组成;随着退火温度的升高,合金中富铜的枝晶间相连成网状,600℃退火后开始有金属间化合物生成,组织不再是完全的固溶体;铸态合金硬度均高于退火态的;铸态合金的抗压强度为1.71GPa,800℃退火后的抗压强度为1.63GPa,断口均属于脆性断口。

AlCrFeCoNiCu high-entropy alloy was prepared in a vacuum arc furnace, and the microstructure and properties of as-cast and annealed alloys were studied. The results show that the as-cast microstrueture of the alloy was dendritic, and it was comprised of solides with face-centered cubic（FCC） structure and body-centered cubic（BCC） structure. The interdendrite phase enriched Cu appeared net shape with the increase of the annealing temperature. The intermetallic compounds began to being found in the alloy after annealing at 600℃, and the microstructure was not complete solide solution. The hardness of as-cast alloy was higher than annealed alloys. The compressive strength of as-cast alloy was 1.71 GPa and that of the alloy annealed at 800℃ was 1.63 GPa, and their compressive fractures all were brittle fracture.