Abstract
The influence of a novel three-step aging on strength, stress corrosion cracking (SCC) and microstructure of AA7085 was investigated by tensile testing and slow strain rate testing combined with transmission electron microscopy (TEM). The results indicate that with the increase of second-step aging time of two-step aging, the mechanical properties increase first and then decrease, while the SCC resistance increases. Compared with two-step aging, three-step aging treatment improves SCC resistance and the strength increases by about 5%. The effects of novel three-step aging on strength and SCC resistance are explained by the role of matrix precipitates and grain boundary precipitates, respectively.
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Foundation item: Project(2012CB619502) supported by the National Basic Research Program of China; Project(2016YFB0300800) supported by the National Key Research and Development Program of China; Project(CALT201507) supported by the CALT Research Innovation Partnership Fund, China; Project(HPCM-201403) supported by the State Key Laboratory of High Performance Complex Manufacturing, China
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Chen, Sy., Chen, Kh., Dong, Px. et al. Effect of a novel three-step aging on strength, stress corrosion cracking and microstructure of AA7085. J. Cent. South Univ. 23, 1858–1862 (2016). https://doi.org/10.1007/s11771-016-3240-8
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DOI: https://doi.org/10.1007/s11771-016-3240-8