Thixoextrusion process of AZ31 Mg wrought alloy

Thixoextrusion process has been developed for improving productivity, reducing extrusion pressure, extending die life and even cost saving due to low energy consumption compared with conventional extrusion process. The present study focuses on AZ31 Mg wrought alloy to investigate the potential industrial applications of thixoextrusion process. The maximum extrusion pressures of thixoextrusion process were very lower than that of hot extrusion process, The average grain sizes of thixoextruded specimens were bigger than average grain sizes of hot extruded specimens. However, the grains of the thixoextruded specimens did not show any asymmetry. Also, the microstructures of thixoextruded specimens did not show any dendrites or rosette-like structures. The values of tensile strength and hardness of thixoextruded specimens were lower than that of hot extruded specimens. The specimens manufactured by the thixoextrusion were usually rather soft and their tensile strength was lower than those of hot extruded specimens. If necessary, their low tensile strength can be improved through appropriate heat.