The quench sensitivity of 7475 aluminum alloy has been comprehensively investigated by hardness testing, electrical conductivity measurements, scanning electron microscopy, and transmission electron microscopy. Based on the end-quenching method and time–temperature–property (TTP) diagram, the key factors affecting the quenching of the studied alloy were identified and are discussed in comparison with other 7000 series alloys. The results indicate that 7475 alloy is relatively sensitive to cooling rate, with a critical temperature range between 300°C and 350°C. The nose temperature of the TTP curve is approximately 330°C, and the incubation period is 1.5 s. When the cooling rate is lower than 12.5°C/s, the density of Guinier–Preston zones and η′ precipitates decreases remarkably, and the width of the precipitate-free zone becomes wider. Simultaneously, coarse η phases precipitate at grain/subgrain boundaries and Al₁₈Mg₃Cr₂ dispersoids. These quench-induced η phases consume numerous solute atoms and therefore suppress the formation of the strengthening precipitates, leading to a deterioration of the mechanical properties.

已经通过硬度测试，电导率测量，扫描电子显微镜和透射电子显微镜对7475铝合金的淬火敏感性进行了全面研究。根据最终淬火方法和时间-温度-性能（TTP）图，确定了影响所研究合金淬火的关键因素，并与其他7000系列合金进行了比较。结果表明，7475合金对冷却速率相对敏感，临界温度范围在300°C至350°C之间。TTP曲线的鼻子温度约为330°C，潜伏期为1.5 s。当冷却速率低于12.5°C / s时，吉尼尔-普雷斯顿区和η的密度'沉淀物显着减少，无沉淀物区域的宽度变宽。同时，在颗粒/亚晶界和Al ₁₈ Mg ₃ Cr ₂弥散体中析出了较粗的η相。这些淬火诱导的η相消耗大量溶质原子，因此抑制了强化沉淀的形成，从而导致机械性能的劣化。