采用铸锭冶金法制备Al-Zn-Mg-xCu-Zr-Cr-Yb超强铝合金，通过金相显微镜和扫描电镜观察以及晶间腐蚀、剥落腐蚀与应力腐蚀等实验，研究Cu含量(0.8%~2.2%，质量分数)对该合金组织与性能的影响。结果表明：随Cu含量降低，合金的残余结晶相数量减少，力学性能提高，抗腐蚀性能先升高后降低。当Cu含量为1.3%时， Al-Zn-Mg-Cu-Zr-Cr-Yb合金的综合性能最佳，抗拉强度、屈服强度和伸长率分别为720.7 MPa，704.2 MPa和9.1%；应力腐蚀指数ISSRT=0.031。%The super-high strength Al-Zn-Mg-Cu-Zr-Cr-Yb alloy was fabricated by ingot metallurgy method. The effect of copper content (2.2%~0.8%) on microstructure and properties of Al-Zn-Mg-Cu-Zr-Cr-Yb alloys was investigated by optical microscopy, scanning electron microscopy, tensile test, intergranular corrosion, exfoliation corrosion and stress corrosion cracking test. The results show that the volume fraction of residual eutectic phase decreases, the mechanical properties increase and the corrosion resistance firstly increases then decreases with decreasing the copper content. The optimum comprehensive properties of Al-Zn-Mg-Cu-Zr-Cr-Yb alloy were obtained when the content of Cu was 1.3%withσ0,σ0. 2,δand ISSRT, reach 720.7MPa, 704.2MPa, 9.1%and 0.031, respectively.
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