Abstract
The Al-Zn-Mg-Cu alloys have been widely used as aircraft structure materials because of their high strength to density ratio. These alloys in the T6 temper are known to be highly susceptible to stress corrosion cracking (SCC). In the present investigation, a comprehensive study on the effect of RRA treatment on the strength and corrosion properties of AA 7049 aluminium alloy has been made. The retrogression heat treatment is varied from 2 min to 60 min at temperatures between 1800C and 2400C; the re-aging treatment was done for 24 hours at 1200C. Within the scope of this investigation, the results indicate that, the susceptibility for corrosion can be decreased by subjecting the alloy for RRA treatment. It is found that the grain boundary precipitate coarsening and enrichment of copper in the grain boundary precipitate are the factors responsible for improvement in reducing susceptibility to SCC.
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Muralidhara, B.K., Ranganatha, R. (2015). A Comprehensive Study on the Effect of Retrogression and Re-Aging on the Properties of Aluminium Alloy Conforming to AA 7049 Specification. In: Hyland, M. (eds) Light Metals 2015. Springer, Cham. https://doi.org/10.1007/978-3-319-48248-4_59
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DOI: https://doi.org/10.1007/978-3-319-48248-4_59
Publisher Name: Springer, Cham
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