Abstract
The effects of pre-aging in retrogression and re-aging (RRA) treatment on microstructure, mechanical properties, and stress corrosion cracking (SCC) behavior of spray-formed 7075 aluminum alloy were investigated by tensile test, slow strain rate test, and transmission electron microscope. The results show that the under aging (120 °C for 16 h) as the pre-aging in RRA treatment can vastly improve the mechanical properties and the SCC resistance of the alloy, compared with early aging (120 °C for 8 h), peak aging (120 °C for 24 h), and over aging (120 °C for 32 h) treatments, the ultimate tensile strength of the alloy is 782 MPa, which is higher than that for peak aging or conventional RRA treatment; and the SCC resistance of the alloy is also excellent after RRA with under aging as pre-aging.
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This research was financially supported under the Program for Liaoning Innovative Research Team in University (LT2012004) and Fok Ying-Tong Education Foundation (121054).
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Su, Rm., Qu, Yd., You, Jh. et al. Effect of Pre-aging on Stress Corrosion Cracking of Spray-formed 7075 Alloy in Retrogression and Re-aging. J. of Materi Eng and Perform 24, 4328–4332 (2015). https://doi.org/10.1007/s11665-015-1728-2
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DOI: https://doi.org/10.1007/s11665-015-1728-2