Effects of Zr, Mn and Cr addition on microstructure and properties of Al-Zn-Mg alloy

doi:10.13251/j.issn.0254-6051.2020.04.006

Abstract

Abstract: Effects of Zr, Mn and Cr additions on microstructure and properties of Al-Zn-Mg alloy were investigated by means of optical microscopy, scanning electron microscopy, transmission electron microscopy and tensile test. The results show that the combined addition of Zr, Mn and Cr in the Al-Zn-Mg alloys leads to precipitates of a large number of (Al,Cr)₃Zr particles with 10-20 nm size, which coherent with the matrix. These irregularity dispersoids can strongly pin the dislocation, and hinder the dislocation movement and subgrain boundary migration and significantly inhibit grain recrystallization and growth of subgrain. The tensile strength and yield strength of Al-Zn-Mg alloy added with Zr, Mn and Cr are increased by 34 MPa and 19 MPa, respectively, which has better processability and mechanical properties.

Key words: Al-Zn-Mg alloy, trace element, microstructure, grain refinement, mechanical properties

CLC Number:

TG146.2⁺1

Deng Ke, Sun Daxiang, Tang Weixue, Wan Li, Cai Zhizhi, Zhou Sigen. Effects of Zr, Mn and Cr addition on microstructure and properties of Al-Zn-Mg alloy[J]. Heat Treatment of Metals, 2020, 45(4): 29-33.

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