Recrystallization Behavior and Texture Evolution of Magnesium Alloy Bending Products under Staggered Extrusion

As an important fabrication process, annealing treatment is conducted to eliminate distortion in magnesium alloy sheets. Second-phase particles can provide nucleation sites for recrystallization grains, and the basal texture is related to the recrystallization behavior. Three experimental Mg-2Zn-based magnesium alloy sheets were investigated by the salt bath annealing process. Combined with variations in hardness softening, evolution of microstructure and basal texture, the effect of second-phase particles on microstructure evolution was analyzed. The results showed that the significant influence of size and distribution of second-phase particles on static recrystallization in magnesium alloy sheets was exhibited, which lead to the formation of two stages in the annealing process, combined with static recovery behavior. Second phase particles with coarse size were beneficial to recrystallization grains’ nucleation and increased recrystallization behavior in the initial stage of annealing. Second-phase particles with fine size inhibited recrystallization behavior and weakened the softening of hardness. The basal texture was weakened by second phase particles at the stage of recrystallization nucleation. The change in basal texture at the stage of grain growth was related to the size of second-phase particles. The regulation of basal texture enhancement can be envisioned by modifying second-phase particles.

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Investigation of the In-Plane Mechanical Anisotropy of Magnesium Alloy AZ31B-O by VPSC–TDT Crystal Plasticity Model

Materials ◽

10.3390/ma12101590 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1590 ◽

Cited By ~ 1

Author(s):

Bo Zhang ◽

Shuangming Li ◽

Huamiao Wang ◽

Weiqin Tang ◽

Yaodong Jiang ◽

...

Keyword(s):

Magnesium Alloy ◽

Texture Evolution ◽

Mg Alloys ◽

Mechanical Anisotropy ◽

Mg Alloy ◽

Loading Path ◽

Crystallographic Structure ◽

Stress Strain ◽

Magnesium Alloy Az31b ◽

R Value

The in-plane mechanical anisotropy of magnesium alloy sheet, which significantly influences the design of the parts produced by Mg alloy sheets, is of great importance regarding its wide application. Though the stress–strain response and texture evolution have been intensively investigated, and the anisotropy of Mg alloy can be significantly substantiated by its R-value, which reveals the lateral response of a material other than the primary response. As a consequence, the conjunction of viscoplastic self-consistent model and twinning and detwinning scheme (VPSC–TDT) is employed to investigate the in-plane anisotropy of magnesium alloy AZ31B-O sheet. The loading cases include both tension and compression along different paths with respect to the processing direction of the sheet. It is revealed that the stress–strain relation, texture evolution, R-value, and involved deformation mechanisms are all loading path-dependent. The unique R-values of Mg alloys are interpreted with the aid of modeling behaviors of Mg single crystals. The results agree well with the corresponding experiments. It is found that the hexagonal close-packed (HCP) crystallographic structure, deformation twinning, and initial basal texture are responsible for the characteristic behavior of Mg alloys.

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