Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Prediction of Microstructure during Hot-working of AZ31 Mg Alloy

AZ31 Mg 합금의 고온 성형 시 미세조직 예측

  • Published : 2008.04.01
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Abstract

In this study, optimum processing condition of rolled AZ31 Mg alloy was investigated by utilizing processing map and constitutive equation considering microstructure evolution(dynamic recrystallization) occurring during hot-working. A series of mechanical tests were conducted at various temperatures and strain rates to construct a processing map and to formulate the recrystallization kinetics in terms of grain size. Dynamic recrystallization(DRX) was observed to occur at a domain of $250^{\circ}C$ and 1/s(maximum dissipation-efficiency region). The effect of DRX kinetics on microstructure evolution was implemented in a commercial FEM code followed by remapping of the state variables. The volume fraction and grain size of deformed part were predicted using a modified FEM code and were compared with those of actual hot forged part. A good agreement was observed between the experimented results and predicted ones.

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References

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