Microstructure and properties of Al-Mg-Si aluminum alloy with different treatments

doi:10.13251/j.issn.0254-6051.2020.02.010

Abstract

Abstract:

Effect of heat treatment on the microstructure and mechanical properties of Al-Mg-Si aluminum alloy microalloying with Y and Zr was investigated by means of scanning electron microscopy, transmission electron microscopy, energy spectrum analysis and tensile test. The results show that the addition of Y and Zr can help to refine the grains of as-cast the alloy. The microstructure of the as-cast alloy has obvious segregation at the grain boundary. The segregation is improved after homogenization treatment at 535 ℃ for 14 h. There exist lots of second phases along the extrusion direction after hot extrusion. Increasing solution temperature, the second phases are dissolved into the aluminum matrix gradually. After aging treatment, a multitude of β″ phases and other fine precipitates are dispersed in the alloy and have a precipitation strengthening effect. The alloy has the best mechanical properties after solution treatment at 530 ℃ for 2 h and aging treatment at 180 ℃ for 8 h, by which the tensile strength is 408 MPa and the elongation is 14.8%.

Key words: Al-Mg-Si aluminum alloy, microstructure, mechanical properties, homogenization, solution treatment, aging treatment

CLC Number:

TG146.2

Zhang Guizhao, Jiang Feng, Zhou Wei, Wang Congkai, Ye Pengcheng. Microstructure and properties of Al-Mg-Si aluminum alloy with different treatments[J]. HTM, 2020, 45(2): 51-55.

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