放电等离子烧结制备AlCoCrFeNi高熵合金的组织演变与力学性能∗

摘要

The AlCoCrFeNi high entropy alloys were fabricated by spark plasma sintering (SPS).Effects of SPS sintering temperature on the density behavior,microstructure and mechanical properties of AlCoCrFeNi high en-tropy alloys were studied using X-ray diffraction (XRD),DSC testing,density testing,scanning electron microscopy (SEM)and mechanical property testing.The results showed that increasing SPS sintering temperature could improve the relative density and mechanical properties of AlCoCrFeNi high entropy alloys.The relative density,compressive strength and yield strength of the AlCoCrFeNi high entropy alloy after sintering at 1200 ℃ were 99.6%,2195 MPa, and 1506 MPa,respectively.During spark plasma sintering,the dual-phase structure (BCC+B2)of AlCoCrFeNi high entropy alloys was transformed into the three-phase structure (BCC+B2+FCC).%采用放电等离子烧结方法(SPS)制备了 AlCoCrFeNi 高熵合金。通过差热分析、密度测试、X 射线衍射、扫描电镜及力学性能测试,研究了 SPS烧结温度对 AlCoCrFeNi高熵合金的致密化行为、组织演变及力学性能影响。结果表明,随着 SPS烧结温度的升高,材料的致密度与抗压缩强度明显提高。1200℃烧结后,AlCoCrFeNi 高熵合金的致密度达到99.6%,抗压缩强度达到2195 MPa,屈服强度达到1506 MPa。在SPS烧结过程中,高熵合金从双相结构(BCC +B2)转变为三相结构(BCC+B2+FCC)。