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Study on a new retrogression and re-aging treatment of spray formed Al–Zn–Mg–Cu alloy

Published online by Cambridge University Press:  26 February 2016

Rui-ming Su*
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Ying-dong Qu
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Jun-hua You
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
Rong-de Li
Affiliation:
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, Liaoning, China
*
a) Address all correspondence to this author. e-mail: suruiming1984@gmail.com
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Abstract

Conventional retrogression and re-aging (RRA) treatment could not be put to good use for combination property of Al–Zn–Mg–Cu alloys. The new RRA treatment fitted for spray formed Al–Zn–Mg–Cu alloy was investigated by transmission electron microscope, tensile, and conductivity tests. The results show that the pre-aging treatment with under aging of 120 °C for 16 h is beneficial for the redissolution of matrix precipitates during retrogression treatment. With the retrogression of 200 °C for 8 min, grain boundary precipitates are discrete and the corrosion resistance of the alloy is drastically increased. After re-aging (120 °C for 24 h) the strength of the alloy is increased again. According to the above-mentioned new RRA treatment, the ultimate tensile strength, yield strength, elongation, and conductivity of the alloy are 791 MPa, 736 MPa, 8.5%, and 39.5% IACS respectively, which is higher than that after conventional RRA treatment.

Type
Articles
Copyright
Copyright © Materials Research Society 2016 

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References

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