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

  • Rui-ming Su (a1), Ying-dong Qu (a1), Jun-hua You (a1) and Rong-de Li (a1)

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.

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a) Address all correspondence to this author. e-mail: suruiming1984@gmail.com

References

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Keywords

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

  • Rui-ming Su (a1), Ying-dong Qu (a1), Jun-hua You (a1) and Rong-de Li (a1)

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