单级固溶对Al-Zn-Mg-Cu合金厚板组织及性能的影响

Effect of single-stage solution treatment on microstructure and properties of Al-Zn-Mg-Cu alloy thick plate

通过OM、SEM、DSC、XRD等分析技术及拉伸、导电率检测手段,对不同单级固溶过程中Al-Zn-Mg-Cu合金微观组织及性能进行表征,研究了不同固溶工艺对合金组织及性能的影响。结果表明,合金在475~482℃范围内进行固溶处理,7055铝合金板材中的第二相发生回溶,基体中残留的第二相含量逐渐减少,合金的导电率显著下降,强度呈先上升后下降趋势,且当固溶温度为479℃,保温时间为1 h时,合金的综合力学性能最优,屈服强度与抗拉强度分别达到377、544 MPa。

Microstructure and properties of Al-Zn-Mg-Cu aluminum alloy after different single-stage solid solution processes were characterized by means of OM,SEM,DSC,XRD,tensile test and conductivity test.The effects of different solution processes on the microstructure and properties of the alloy were studied.The results show that the second phase in the 7055 aluminum alloy plate dissolves and the retained content of the second phase in the matrix gradually decreases when the alloy solution treated within the range of 475-482℃.Meanwhile,the conductivity of the alloy significantly decreases.The strength shows a trend of first increasing and then decreasing.Moreover,the alloy exhibits excellent comprehensive mechanical properties,when solution treated at 479℃for 1 h,the yield strength and the tensile strength of the alloy reach 377 MPa and 544 MPa,respectively.