The hot deformation behavior of an Al-Zn-Mg-Cu alloy was investigated by hot compression test at deformation temperatures varying from 320 to 440 °C with strain rates ranging from 0.01 to 10 s⁻¹. The results show that the Mg(Zn, Cu)₂ particles as a result of the sufficient static precipitation prior to hot compression have an influence on flow softening. A constitutive model compensated with strain was developed from the experimental results, and it proved to be accurate for predicting the hot deformation behavior. Processing maps at various strains were established. The microstructural evolution demonstrates that the dominant dynamic softening mechanism stems from dynamic recovery (DRV) and partial dynamic recrystallization (DRX). The recrystallization mechanism is continuous dynamic recrystallization (CDRX). The microstructure observations are in good agreement with the results of processing maps. On account of the processing map and microstructural observation, the optimal hot processing parameters at a strain of 0.6 are at deformation temperature range of 390–440 °C and strain rate range of 0.010–0.316 s⁻¹ with a peak efficiency of 0.390.

A dense alumina ceramic coating was formed on UNS A97075 Al alloy by plasma electrolytic oxidation (PEO). An efficient and environmentally friendly silane layer was prepared to seal the PEO coating. The scanning electron microscopy (SEM) results showed that the PEO coating was completely sealed by the silane layer. The electrochemical corrosion evolution of the silane sealed PEO composite coating was studied by electrochemical impedance spectroscopy (EIS). Based on the EIS data, the corrosion evolution of the silane sealed composite coating could be divided to three stages during 576 h of immersion test, and the silane coating acted as a good physical barrier in the immersion test, effectively delayed the corrosion process and improved the corrosion resistance.