Effect of isothermal temperature on semi-solid microstructure of 7075 aluminum alloy prepared by rolling SIMA method

doi:10.13251/j.issn.0254-6051.2022.02.029

Abstract

Abstract: 7075 aluminum alloy semi-solid billets were prepared by strain induced melting activation(SIMA) method with pre-deformation modes of synchronous rolling and asynchronous rolling respectively. The effects of roll diameter ratio and isothermal temperature on microstructure evolution of pre-deformed sheet during heat treatment were studied. The results show that with the increase of isothermal temperature,a large amount of liquid phase are formed in the primary solid phase, and a large number of eutectic phases appear after solid inter-granular cooling. Under the same heat treatment conditions, the pre-deformation process of asynchronous rolling can produce more liquid phase and the semi-solid process is faster than the pre-deformation process of synchronous rolling. The optimum process conditions for obtaining semi-solid billets are asynchronous rolling pre-deformation and isothermal temperature of 610 ℃.

Key words: rolling process, 7075 aluminum alloy, semi-solid heat treatment, isothermal temperature, microstructure

CLC Number:

Yu Xinlei, Zheng Xiaoping, Cao Tong, Tian Yaqiang, Chen Liansheng. Effect of isothermal temperature on semi-solid microstructure of 7075 aluminum alloy prepared by rolling SIMA method[J]. Heat Treatment of Metals, 2022, 47(2): 164-167.

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