The effects of processing condition variations in the retrogression and re-ageing (RRA) treatment of AA7150 have been investigated. The results reveal that the corrosion resistance and strength of RRA-treated samples are sensitive to the pre-ageing temperature and retrogression heating rate. With an intermediate pre-ageing temperature of 60 °C and a slow retrogression heating rate of 5 °C/min, RRA-treated samples can be tailored towards a good combination of both corrosion resistance and strength, owing to a smaller potential difference between grain-boundary precipitates and the matrix, and a larger volume fraction of strengthening precipitates in the matrix.
Xu, D., Birbilis, N., & Rometsch, P. (2012). The effect of pre-ageing temperature and retrogression heating rate on the strength and corrosion behaviour of AA7150. Corrosion Science, 54, 17 - 25. https://doi.org/10.1016/j.corsci.2011.08.042