AlFeNiCrCoTi_(0.5)高熵合金颗粒增强6061铝基复合材料的制备与性能

Preparation and properties of AlFeNiCrCoTi_(0.5)high entropy alloy particle reinforced 6061 aluminum matrix composites

采用机械合金化工艺制备AlFeNiCrCoTi_(0.5)高熵合金粉末,通过先冷等静压、后等径角挤压的方法制备(AlFeNiCrCoTi_(0.5))p/6061Al复合材料。研究AlFeNiCrCoTi_(0.5)高熵合金粉末各单质金属间的合金化行为及球磨时间对合金粉末形貌的影响,分析不同体积分数对(AlFeNiCrCoTi_(0.5))p/6061Al复合材料的组织和性能。结果表明:AlFeNiCrCoTi_(0.5)金属粉末合金化时间随单质金属的熔点提高而增加,且金属熔点越高,其合金化越先进行,当球磨时间达到70 h时,AlFeNiCrCoTi_(0.5)金属粉末完全合金化,形成FCC+BCC的双相固溶体结构。6061Al基体与AlFeNiCrCoTi_(0.5)高熵合金增强体之间形成元素相互浸渗的过渡层。随着增强体体积分数的提高,增强体聚集行为加剧,抗拉强度提高,塑性降低。当体积分数为10%时,复合材料获得良好的综合性能,与6061Al基体相比,抗拉强度提高21.8%,伸长率降低7.4%。T6处理后其抗拉强度和伸长率分别为284.05 MPa和11.51%。

AlFeNiCrCoTi_(0.5)high entropy alloy powder was prepared by mechanical alloying,and(AlFeNiCrCoTi_(0.5))p/6061Al composites were prepared by cold isostatic pressing combined with equal-channel angular pressing.The alloying behavior between elemental metals and effects of milling time on powder morphology of high entropy alloy were investigated.The microstructure and properties of(AlFeNiCrCoTi_(0.5))p/6061Al composites with different volume fractions were analyzed.The results show that the alloying time of AlFeNiCrCoTi_(0.5)metal powder increases with the increase of melting point of the elements.The higher the melting point of the elements,the earlier the alloying.AlFeNiCrCoTi_(0.5)metal powder is fully alloyed and forms a FCC+BCC two-phase solid solution structure after 70 h ball milling time.A transition layer of element infiltration of elements is formed between Al matrix and the reinforcement.With the increase of the volume fraction of reinforcement,the agglomeration of reinforcement is intensified,the tensile strength increases and the plasticity decreases.When the volume fraction is 10%,the composites have good comprehensive properties.Compared with 6061 aluminum matrix,the tensile strength increases by 21.8%and the elongation decreases by 7.4%.For the composites after T6 treatment,the tensile strength and the elongation are 284.05 MPa and 11.51%,respectively.