Effects of fabrication methods on deformability andmicrostructure of Mg-Zn-Zr wrought alloy
(1. Metal Forming Technology R&D Group, Korea Institute of Industrial Technology, Incheon 406-840, Korea;
2. Department of Chemical Engineering and Materials Science,
University of Southern California, Los Angeles, CA 90089, USA;
3. Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea)
2. Department of Chemical Engineering and Materials Science,
University of Southern California, Los Angeles, CA 90089, USA;
3. Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea)
Abstract: The effects of fabrication processing methods on the workability of Mg-Zn-Zr wrought magnesium alloy (ZK60A) were investigated based on the microstructure and inherent internal defects. Three different billets, semi-continuously cast, semi-continuously cast and subsequently extruded, and die-cast, were fabricated and uniaxially compressed at elevated temperatures and two different strain rates to determine the deformation capabilities. The grain structure of the billets was investigated using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The internal defects were inspected by an X-ray scanner. The enhanced deformability was observed in semi-continuously cast billet compared to the one fabricated by conventional die-casting, and the subsequent extrusion further improved the deformability.
Key words: magnesium; continuous casting; workability; electron backscatter diffraction (EBSD)