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 MSA  Vol.7 No.1 , January 2016
Effect of Retrogression and Reaging on Stress Corrosion Cracking of Spray Formed Al Alloy
Abstract: Stress corrosion cracking (SCC) resistance of a spray formed Al-Zn-Mg-Cu alloy underwent retrogression and reaging (RRA) was studied by slow strain rate tests in dry air and 3.5 wt% NaCl solution. The results showed that after RRA treatment, interrupted η phases at grain boundaries and slightly wide precipitate free zones could decrease SCC susceptibility of the alloy. Lots of reticular dislocations appeared in deformation process could prevent hydrogen induced cracking, and then SCC. Abundance transgranular dispersive η' phases separated out again promoted tensile strength to 759.4 MPa. The fracture ways of the specimens were dimple fracture in dry air and sub-cleavage fracture in 3.5% NaCl solution.
Cite this paper: Su, R. , Qu, Y. , Li, X. , You, J. and Li, R. (2016) Effect of Retrogression and Reaging on Stress Corrosion Cracking of Spray Formed Al Alloy. Materials Sciences and Applications, 7, 1-7. doi: 10.4236/msa.2016.71001.
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