Effect of pre-solution treatment on rheological behavior and microstructure of AZ80 magnesium alloy

doi:10.13251/j.issn.0254-6051.2020.01.016

Abstract

Abstract: Pre-solution treatment was conducted on AZ80 magnesium alloy before isothermal hot compression. The influences of pre-solution treatment on the recrystallization, microstructure and rheological behavior of AZ80 magnesium alloy under different compression conditions were compared and analyzed by means of isothermal hot compression experiment, metallographic microscope, scanning electron microscope, transmission electron microscope, X-ray diffraction analysis and electron backscattering diffraction. The results show that after the pre-solution treatment of 410 ℃×2 h, the coarse Mg ₁₇ Al ₁₂ phase in the initial forged material has dissolved, and during the isothermal hot compression tests, the rheological stress of the material after pre-solution treatment is lower on the whole than that of the initial forged material under the same compression condition, i.e., the peak stress is decreased by 10-30 MPa, indicating that the pre-solution treatment softens the material in the process of isothermal hot compression and thus improves the plastic deformation ability during the processing. After the pre-solution treatment of 410 ℃×2 h, and in the deformation temperature zone of 300 ℃ and below, the recrystallization mechanism of the material changes from discontinuous dynamic recrystallization into continuous dynamic recrystallization, and the recrystallization volume fraction increases significantly, the grains are fully refined and the plasticity is improved as well.

Key words: AZ80 magnesium alloy, grain refinement, isothermal hot compression, pre-solution treatment

CLC Number:

TG156.94

Luo Shenglan, Huang Shiquan, Yi Youping. Effect of pre-solution treatment on rheological behavior and microstructure of AZ80 magnesium alloy[J]. HTM, 2020, 45(1): 76-83.

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