摘要
采用光学显微镜和扫描电镜(SEM)研究7075高强铝合金的固溶时效工艺,利用正交试验法对工艺参数进行了优化。结果表明:7075铝合金经570℃×4 h固溶,水冷+150℃×16 h时效处理后,屈服强度、抗拉强度和显微硬度分别提高约81.5%、92.1%和164%,伸长率几乎没有降低,综合力学性能较好。主要原因是随着温度升高第二相颗粒在α(Al)基体中溶解的量增加,而在随后的时效过程中大量Mg Zn2等第二相在晶界上析出起到了一定的强化作用。
Solution treatment and aging process of the 7075 high strength aluminum alloy were studied by means of optical microscope and scanning electron microscope （SEM）. The process parameters were optimized by orthogonal experiment. The results show that, after being solution treated at 570 ℃ for 4 h, water quenched and then aged at 150 ℃ for 16 h, the 7075 aluminum alloy can obtain good comprehensive mechanical properties, and the proof yield strength, tensile strength and hardness of specimens increase by 81.5% , 92.1% and 164% , respectively, but the elongation nearly does not decrease. The main reason is that with the increase of temperature, the amount of secondary phase particles dissolved completely in the α-A1 matrix, then in the subsequent aging process, a large amount of second-phase particles including of MgZnzprecipitate on the grain boundaries, which plays a strengthening role.
出处
《金属热处理》
CAS
CSCD
北大核心
2017年第12期148-154,共7页
Heat Treatment of Metals
基金
国家自然科学基金(51601079)
常州市高技术研究重点实验室项目开放基金(CM20153001)
关键词
7075铝合金
固溶时效
力学性能
显微组织
7075 aluminum alloy
solution and aging treatment
mechanical properties
microstructure
