The influences of the expansion equal channel angular extrusion operation on the strength and ductility of AZ80 magnesium alloy

The as-cast AZ80 magnesium alloy was processed through the expansion equal channel angular extrusion (Exp-ECAE) operation. The process was conducted with various test conditions by varying the temperature, ram velocity and number of passes. Then, the mechanical and microstructural characteristics of the product were investigated. The grain size reduced by 64% in the component processed at 225 °C and with a ram velocity of 6 mm/min, while the UTS, microhardness and the elongation showed, respectively, 2, 1.6 and 1.8 times improvements compared with the as-cast billet. The possibility of deforming AZ80 Mg alloy at temperatures below 200 °C was also examined. Finally, the Exp-ECAE technique succeeded in processing this alloy at 180 °C without applying any external back-pressure. Processing under such condition resulted in 2.4 times improvement in the product strength, in comparison with the as-cast billet.