Effect of annealing temperature on microstructure and mechanical properties of rolled wrought Mg-Li alloy

doi:10.13251/j.issn.0254-6051.2022.12.006

Abstract

Abstract: Microstructure evolution, mechanical properties and deformation mechanism of Mg-8Li-1Al-0.5Sn alloy after cold-rolling (deformation of 75%) and then isothermally annealed for 1 h at 150, 200, 250 and 300 ℃, respectively, were studied. The results show that the elongation increases first and then decreases with the increase of annealing temperature. When the annealing temperature is 200 ℃, the elongation of the alloy reaches the best, which is 40%, and compared with the cold-rolled alloy, the strength without weakening is 212 MPa, and the elongation is increased by 24.4%. The ductility of the alloy is improved mainly because that the annealing promotes the transformation of α phase from strip to bamboo-like, alleviates stress concentration and promotes static recrystallization and grain refinement of β phase. In addition, the α phase rolling texture is angular deflected during annealing, which retains the {1010} grain direction texture conducive to slip and promotes the elongation of the alloy.

Key words: wrought Mg-Li alloy, cold rolling, annealing, microstructure evolution, mechanical properties

CLC Number:

TG146.2

Xu Weijian, Wang Siyu, Wang Bingxing. Effect of annealing temperature on microstructure and mechanical properties of rolled wrought Mg-Li alloy[J]. Heat Treatment of Metals, 2022, 47(12): 36-42.

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