| Magnesium alloys have a wide of potential applications due to their many advantages such as high specific strength, good electrical conductivity, ease of recycling. However, wrought magnesium alloys have a low formability at room temperature owing to their hexagonal crystal structure and strong basal texture, which greatly limits their wide applications in industry. Therefore, the studies on the plastic deformation mechanisms and static recrystallization behavior have an important guiding significance for improving the formability of magnesium.The compressive deformation behavior in a hot-extruded AZ31 magnesium alloy with fiber texture was carried out by OM, XRD and EBSD methods. The role of{10-12} tension twinning on plastic deformation behavior was discussed. The static recrystallization behavior in a cold-rolled AZ31 magnesium sheet was performed. The microstructural and textural evolutions and mechanical property was researched.The main conclusions obtained are as follows:(1) Uniaxial compressive stress-strain curves of the as-extruded AZ31 magnesium exhibits typical three plastic deformation stages. The{10-12} tension twinning dominates the early deformation, which decides the low strain hardening rate. The{10-12} tension twinning even expands to the entire grain when the compression deformation continues, which leads to strong{0002} basal texture and high strain hardening rate. The strain hardening rate reduces at the later deformation, because the non-basal planes slip and{10-11} contraction twinning play the dominating role. (2) Mass of {10-11} contraction twinning,{1011}-{10-12} secondary twinning and shear bands occur during cold rolling for AZ31 magnesium sheet, which are effective nucleation sites in static recrystallization annealing. Pre-cold-rolling and subsequently annealing are an effective way to weaken the basal texture and refine grains, which can significantly improve the mechanical properties for AZ31 magnesium sheet. |
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