Process parameters such as soaking time and forming temperature are critical for the isothermal warm forming performance and post-form mechanical properties. The isothermal warm forging process of AA7075-T4 aluminum alloy has been simulated through the warm compression at 180 ℃. The warm deformation schedule including fast heating and short-term initial holding is found to be advantageous for enhancing the formability of high-strength AA7075-T4 alloy due to the reduced flow strength and significantly increased ductility. As revealed by differential scanning calorimetry and transmission electron microscopy, the natural ageing clusters quickly dissolve, then the GP zones and even η'/η₂ phases form during initial holding at 180 ℃ for 4 min. The optimum balance of warm-deformability and subsequent age hardening potential at 120 ℃ is obtained with an initial holding for less than 30 s, by restricting the growth of coarsening precipitates before isothermal warm deformation. The warm compression induced dislocations are largely retained during post-ageing, accelerating the hardening kinetics and promoting the formation of a high density of η'/η₂ precipitates in the peak-aged sample. Through considering the reversion of natural ageing clusters and solutes reprecipitation during the initial holding and post-ageing, a temperature-time-property sketch is proposed to explain the relationship between the warm deformation temperature, initial holding time and the obtained hardness for the AA7075-T4 alloy. This study could guide the optimization of warm forming process and is fruitful for establishing an accurate microstructure-based model for the warm deformation of AA7075-T4 aluminum alloy.

诸如均热时间和成型温度的工艺参数对于等温热成型性能和成型后的机械性能至关重要。通过180℃的热压缩模拟了AA7075-T4铝合金的等温热锻工艺。发现包括快速加热和短期初始保持的热变形时间表由于降低的流动强度和显着增加的延展性而对于增强高强度AA7075-T4合金的可成形性是有利的。所揭示的通过差示扫描量热和透射电子显微镜，自然老化簇迅速溶解，则GP区和甚至η'/η ₂最初在180℃下保持4分钟的过程中会形成两相。通过限制等温热变形前的粗大析出物的生长，在初始保持时间少于30 s的情况下，获得了120℃时的热变形能力和随后的时效硬化潜力的最佳平衡。温暖的压缩引起的位错被期间大量保留老化后，加快硬化动力学和促进的η'/η的高密度的形成₂在峰值时效样品中出现沉淀。通过考虑初始保持和后老化过程中自然老化团簇的还原和溶质的再沉淀，提出了温度-时间-性能图，以解释AA7075-的热变形温度，初始保持时间与获得的硬度之间的关系。 T4合金。该研究可指导热成形工艺的优化，为建立基于AA7075-T4铝合金的热变形的基于微观组织的精确模型具有重要意义。