Zn含量对喷射成形7×××系高强铝合金组织与性能的影响

Influence of Zn content on microstructure and properties of spray-formed 7××× series aluminum alloys

采用喷射成形技术制备了不同Zn含量的7×××系超高强铝合金,研究了Zn含量对材料的显微组织及室温力学性能的影响.结果表明:喷射成形工艺可显著细化晶粒,有效抑制合金内的偏析,获得细小、均匀的等轴晶组织,采用相同工艺制备的不同Zn含量的材料的晶粒尺寸为10～20μm.喷射成形制备的7×××系超高强铝合金中的主要组成相为:α(Al)、六方晶格的MgZn2、四方晶格的Al2Cu和面心斜方晶格的Al2CuMg.Zn含量在9.5%～11.5%时,经过适当的热处理,材料的强度可以达到800 MPa以上.综合考虑材料的组织和性能,确定喷射成形7×××系铝合金中的Zn含量应控制在9.5%～11.5%.

The uhra-high strength aluminum alloys with high Zn content were prepared by spray forming technology, and the microstructure and properties of alloys were studied. The results show that the as-deposited materials reveal a spheroid grain morphology with an average grain size of 10 - 20 μm. XRD analysis results indicate that the as-deposited alloys consist of α（AI）, MgZn2, AI2Cu and AI2CuMg phases. The ultimate tensile strength of the alloy with 9.5% - 11.5% Zn content can get to 815 MPa after T6 heat treatment. Based on the microstructure and properties, the Zn content should be controlled between 9.5% and 11.5%.