【摘要】 采用喷射成形技术制备了高Zn含量的超高强度Al-12.40Zn-2.68Mg-2.40Cu合金(质量分数, ％).对合金进行热挤压,在不同固溶温度和时间下对挤压合金进行固溶处理,并进行力学性能测试.结果表明:随着固溶温度的升高及固溶时间的延长,第二相富Cu颗粒随之相应溶解,再结晶晶粒合并与长大;当固溶温度达到490℃时,富Cu颗粒相基本溶解,合金完全再结晶.合金进行T6热处理后,抗拉强度达到800 MPa以上,延伸率为7.5％.更多还原

【Abstract】 Ultrahigh strength Al-12.40Zn-2.68Mg-2.40Cu alloy (mass fraction, %) prepared with the spray depositiqn method was hot extruded and heat treated at different temperatures and holding times. Microstructure characterization of the alloy was carried out by OM, SEM and XRD. The results show that with the increase of temperature and holding time during solid-solution treatment, the particles of Cu rich phase were dissolved and recrystallized grains grew up through the coalition of the grains. When the temperature of solid-solution treatment was up to 490 ℃ , the Cu-rich particles were dissolved completely and recrystallized process was also completed. After T6 heat treatment, the tensile strength of the alloy is over 800 MPa and the elongation is 7.5%.更多还原