Design & Manufacturing

Korean Society of Die & Mold Engineering (한국금형공학회)
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A study on equal-channel angular extrusion process conditions for improving mechanical properties of magnesium alloy

기계적 특성 향상을 위한 마그네슘 합금의 등틍로각압출 공정 조건에 관한 연구

  • Received : 2016.01.28
  • Accepted : 2016.03.02
  • Published : 2016.03.03
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Abstract

Although magnesium alloy has received much attention to date for its lightweight and high specific strength, their applications are impeded by the low formability which is caused by the hexagonal crystal structure at room temperature. In general, equal-channel angular extrusion(ECAE) is recognized as one of the attractive severe plastic deformation techniques where the processed bulk metals generally achieve ultrafine-grained microstructure leading to improved physical characteristics and mechanical properties. ECAE process has several parameters such as angle of die, process temperature, process route and speed. During ECAE process of Mg alloy, these parameters has great influence on the extrudability and the mechanical properties of alloy. The aim of this study is to estimate the influences of process conditions on the formability of AZ31 and AZ31-CaO alloys. Mg alloys are processed through ECAE at elevated temperatures using three types of die with channel angle of $90^{\circ}$, $110^{\circ}$, $135^{\circ}$ using route $B_c$, respectively. This study discusses the feasibility of using ECAE to improve both formability and strength on magnesium alloys by comparative analyzing the mechanical properties and microstructural evolution in each condition.

Keywords

References

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