Effect of predeformation on semi-solid microstructure of ZK60+RE magnesium alloy
(Southwest Technique and Engineering Institute, Chongqing 400039, China)
Abstract: Microscopical techniques were used to provide the semi-solid microstructure evolutions of ZK60+RE alloys formed by compression and equal channel angular extrusion(ECAE), respectively. It is found that after compression and ECAE, as-cast microstructures exhibit an obvious directional characteristic. The predeformation exerts a significant influence on the formation of thixotropic microstructures during partial remelting. Coalescence and Ostwald ripening are operative in the semi-solid mixture for both compression and ECAE formed alloys. Furthermore, the degree of spheroidization of ECAE formed alloy is better than that of compression formed alloy in appearance.
Key words: microstructure; ZK60+RE magnesium alloy; semi-solid state; coalescence; Ostwald ripening