Abstract |
This study has been investigated the deformation behavior of a hot-extruded Mg-Zn-RE (RE: rare earth elements) alloy containing Mg12(RE) particles at the elevated temperatures. The particles are intrinsically produced by breaking the eutectic structure of the alloy during the hot-extrusion process. The grain size of the extruded Mg-Zn-RE alloy developed via dynamic recrystallization is around 10 μm. Under the heat treatment at 200℃ up to 48 hr, no change has been observed on the microstructure and mechanical properties due to the pinning effect of the thermally stable particles. Under the tensile test condition in the initial strain-rate range of 1×10-3s-1 and the temperature range up to 200℃, the alloy shows yield strength of 270 MPa and elongation to failure around 9% at room temperature and yield strength of 135 MPa at 200℃. Furthermore, although the alloy contains large amount of the second phase particles around 15%, it shows excellent hot-workability possibly due to the presence of the thermally stable interface between the particles and the matrix. |
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Key Words |
Mg alloy, misch metal, mechanical properties, hot extrusion |
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