【摘要】 通过调控压铸铝合金(A380)中Zn的含量，研究Zn含量对合金的微观结构和性能的影响，样品中Zn的质量分数分别为17.5%, 19.5%, 21.5%.通过对室温下工程应力-应变曲线、真实应力-应变曲线和应变硬化率曲线的分析，发现超过屈服点后，真实应力显著大于名义应力，这是由于计算时进行了材料体积守恒的假设.采用应变硬化率来表征材料的均匀塑性变形能力.结果表明：随着Zn含量的增加，合金的强度和塑性均有所提升，其中，试样的抗拉强度从压铸铝合金(A380)的240 MPa提升至Al-Zn-Si-Cu合金的320 MPa,提升幅度为33%.结合微观组织分析可知：Zn元素主要固溶于Al基体中，起到固溶强化的作用，从而提高合金的强度.更多还原

【Abstract】 The influence of Zn content on the microstructure and properties of die cast aluminum alloy(A380) is studied by regulating the Zn content. The Zn contents by mass of the samples are 17.5%, 19.5%, and 21.5%, respectively. A study of engineering stress-strain curve, real stress-strain curve, and strain hardening rate curve at room temperature finds that after exceeding the yield point, the actual stress is significantly greater than the nominal stress, which is due to the assumption of material volume conservation during calculation. Therefore, this paper uses strain hardening rate to characterize the uniform plastic deformation ability of the material. The research results indicate that with the increase of Zn content, the strength and plasticity of the alloy increase. Among them, the tensile strength increases from 240 MPa for A380 die cast aluminum alloy(as cast) to 320 MPa for Al-Zn-Si-Cu alloy, with an increase of 33%. Based on the analysis of microstructure, it can be concluded that Zn element mainly dissolves in the Al matrix in aluminum alloy, playing a role in solid solution strengthening and improving the strength of the alloy.更多还原