Enhanced Tensile Ductility of AZ80 Magnesium Alloy

Tensile behaviors of extruded and rolled AZ80 Mg alloy were investigated with elongation-to-failure tensile tests at constant temperatures of 300 degrees C, 350 degrees C, 400 degrees C, and 450 degrees C, and constant strain rates of 10(-2) s(-1) and 10(-3) s(-1). Experimental data show that the material exhibits tensile ductilities of over 100% at 400 degrees C and 450 degrees C, featured by long steady state deformation. Microstructure studies show that annealed coarse grains were remained in the gauge region during the tensile tests, and the enhanced tensile ductilities resulted from dislocation creep, other than dynamic recrystallization or grain boundary sliding. Cavity evolution and recrystallized coarse grains near fracture end caused premature failure of the material.