MICROSTRUCTURE AND TEXTURE EVOLUTION OF MICRO- ALLOYED MAGNESIUM-ZINC-NEODYMIUM ALLOYS

摘要

The application of wrought magnesium (Mg) alloys was expanded by the addition of rare-earth (RE) elements due to the enhancement of formability, which can be attributed to the formation of non-basal texture components. Most previous studies on RE containing Mg alloys employed considerable amounts (above 0.5 wt.%) of RE elements. To economize on RE resources, two Mg-1Zn-xNd (wt.%) alloys with reduced amounts of Nd, i.e. x= 0.1 and 0.5 wt.%, were designed for the present work. The two alloys were subjected to hot rolling at 450°C to a total reduction of 45% in two passes. Post-deformation annealing was then employed on the as-rolled specimens at various temperatures to generate microstructures and textures by static recrystallization. The addition of 0.1% Nd did not have a strong impact on the alloy. However, strong recrystallization suppression was observed with 0.5 wt% addition of Nd. A texture with basal poles splitting toward transverse direction (TD) was obtained after rolling of the Mg-lZn-0.5Nd alloy. The texture was further modified after annealing and a non-basal texture with RD and TD splitting was achieved.