Pre-deformation on microstructure and properties of 7085 ultra strength aluminum alloy ring

doi:10.13251/j.issn.0254-6051.2024.09.028

Abstract

Abstract: Mechanical properties and stress corrosion resistance of 7085 aluminum alloy ring after solution treatment-pre-deformation(1.5%, 3%, 5%)-aging treatment were studied by means of residual stress, tensile, impact and stress corrosion tests, and the change characteristics of microstructure were analyzed and observed by means of optical microscope(OM), scanning electron microscope(SEM), transmission electron microscope(TEM). The results show that the maximum residual stress of the 7085 aluminum alloy ring decreases by 87.2% when the pre-deformation is 3%. Tangential direction(TD) tensile strength, yield strength and elongation are significantly higher than that of radial(RD) and axial direction(AD). The anisotropy index of tensile strength and yield strength of the alloy change little after pre-deformation, but the anisotropy index of elongation increases significantly. In advance, the increase of the deformation is helpful to improve its stress corrosion resistance. TEM microstructure of the alloy shows that with the increase of deformation, the size of intragranular precipitates increases, as well as the density and the volume fraction of precipitates, the grain boundary precipitates (GBPs) coarsen, the particle spacing of GBPs increases, and the width of precipitation free zone (PFZ) increases gradually.

Key words: pre-deformation, aluminum alloy ring, mechanical properties, stress corrosion

CLC Number:

TG146.2

Liu Qiang, Sheng Zhiyong, Zhang Chao, Li Jie, Chen Ze, Chen Songyi, Chen Kanghua. Pre-deformation on microstructure and properties of 7085 ultra strength aluminum alloy ring[J]. Heat Treatment of Metals, 2024, 49(9): 176-184.

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