合金元素对A7N01铝合金组织及性能的影响

Influence of alloying elements on microsture and properties of A7N01 aluminum alloy

采用正交试验法设计出八种不同成分的A7N01铝合金,加工后通过光学显微镜观察合金铸锭的金相显微形貌;经自然时效一月后,借助拉伸试验机、SEM观察及EDS分析对合金的强度和塑性进行研究;并采用正交分析法中的极差分析法、方差分析法分析合金的力学性能。结果表明,微量元素Mn、Cr、Zr、Ti可细化合金铸锭晶粒,其作用依次是:Mn、Cr联合作用大于Ti大于Zr;合金的强度受Zn、Mg、Cu元素含量影响较大;合金的拉伸断口是以韧窝为主的韧性断裂,且断口中存在杂质元素Fe和Si。

Eight kinds of A7N01 aluminum alloys with different components in elements were designed by orthogonal test method, then the microstructure of their alloy ingots were studied by optical microscope after they were processed.The strength and elongation were researched by means of tensile testing machine ,SEM and EDS after one month＇s natral aging.The mechanical properties were discovered by means of extremum difference analysis , multiple linear regression analysis method and variance analysis method of orthogonal experiment. The results show that the gains of alloy ingots can been refined with the addition of trace elements for Mn,Cr, Zr and Ti.Mn combines with Cr is first,then is Ti,followed by Zr in the sequence of element effects. The Mechanical properties were effect obviously by content of Zn,Mg,Cu elements.The frature menchanism exhibited ductile frature with much dimple,and there is impurity elements of Fe and Si in fracture.