Microstructural characteristics, mechanical and corrosion properties of a low-alloyed Mg alloy after different deformation processing

Abstract. In the evolution of characteristics in Mg alloys, combined influence grain refinement by severe plastic deformation (SPD) and alloying elements usually plays a crucial role. Rare earth (Y, Gd, Nd) combination with Zn have substantial impact on various compositions. this study, new dilute extruded Mg-Zn-Gd-Y-Nd alloy was exposed to 5 passes equal channel angular pressing (ECAP), die 90° angle following route Bc. The initial temperature 300°C, it dropped 200°C 25°C step until fifth pass. Initial deformed samples were subjected hardness testing, optical scanning electron microscopy (SEM) examinations corrosion tests. After run ECAP at 200°C, necklaces fine recrystallized grains along boundaries elongated unrecrystallized transformed an ultrafine grained microstructure. SEM images reveal presence very nanoscale dynamic recrystallization (DRX) nuclei context ECAPed alloy. Furthermore, measures show increase from starting state pass ECAP. caused recrystallization, which resulted higher percentage freshly produced boundaries. inclusion rare increased controlled rate during On other hand, cause changes density distribution defects, affect behavior magnesium alloys. Additionally, comparison as cast condition extruded-annealed, as-extruded better resistance, respectively. It can be concluded that has positive effect decreasing while homogenization microstructure is more effective.