Effect of high-temperature short-time solution treatment on microstructure and properties of ultra-high strength Al-Zn-Mg-Cu alloy forging

doi:10.13251/j.issn.0254-6051.2022.07.004

Abstract

Abstract: Effect of high-temperature short-time solution treatment (temperature of 475-480 ℃ and time of 0-7 min) on microstructure and properties of high alloying Al-Zn-Mg-Cu alloy forging was studied by means of optical microscope, scanning electron microscope and room temperature tensile test. The results show that high-temperature short-time solution treatment can effectively improve the tensile strength and elongation of as-aged Al-Zn-Mg-Cu alloy forging. With the increase of temperature or time, the coarse retained second phase at the grain boundary gradually dissolves back into the aluminum matrix. When the temperature is too high or the time is too long, the equiaxed grains coarsen and the microstructure burns over. Through comparative analysis and combined with the actual production situation, it is determined that the most suitable high-temperature short-time solution treatment is 475 ℃ for 3 min, under which the minimum tensile strength of the forging is 680 MPa in the 45° direction and the lowest elongation is 4.7% in LT direction.

Key words: Al-Zn-Mg-Cu alloy, high-temperature short-time solution treatment, microstructure, property

CLC Number:

TG146.2

Wang Shaohua, Zhong Liwei, Ma Zhifeng. Effect of high-temperature short-time solution treatment on microstructure and properties of ultra-high strength Al-Zn-Mg-Cu alloy forging[J]. Heat Treatment of Metals, 2022, 47(7): 20-26.

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