MICROSTRUCTURE, TEXTURE AND MECHANICAL PROPERTIES OF Mg-Gd-Nd-Y-Zn ALLOY MANUFACTURED UNDER VARIOUS THERMOMECHANICAL TREATMENTS

摘要

In present work, the impact of various thermomechanical treatments on the microstructure and texture evolutions, as well as mechanical properties of the Mg-6.5Gd-l.3Nd-0.7Y-0.3Zn alloy was investigated. The results demonstrate that the microstructures of hot extruded 2 mm and 8 mm alloy sheets, as well as hot rolled 3 mm alloy sheet are characterized by fully recrystallized grains with a large amount of crushed eutectic phase particles. For the 3 mm alloy sheet, heavy deformation produced by the combination of hot extrusion and hot rolling leads to the smallest recrystallized grain size among these alloy sheets. In addition, these alloy sheets exhibit weakened or modified basal textures. The extruded 2 mm alloy sheet shows a weak basal texture with the spread of basal pole towards transverse direction of the sheet. Yet for the extruded 8 mm alloy sheet and rolled 3 mm alloy sheet, the splitting basal poles towards transverse direction of the sheets are obtained. The different microstructures and textures, produced by various thermomechanical treatments, play an important role in the mechanical properties, and thus planar anisotropies of these alloy sheets.