Effect of pulse-current heating multiple forging on mechanical properties of Mg–Nd–Zn–Zr alloy

The effects of pulse current heating on microstructure evolution and mechanical property of Mg–Nd–Zn–Zr magnesium alloy during multiple forging are investigated. The results of uniaxial tensile test show that tensile strength, yield strength and elongation of the alloy are improved with the increasing of forging passes. Moreover, under the condition of pulse current heating, this promotion effect is more obvious. The results of microstructure analysis show that recrystallisation occurs during the deformation, and the recrystallisation is obviously accelerated by pulse current. The magnesium alloy billet with fine grains is obtained eventually. Theoretical analysis shows that pulse current can increase the recrystallisation nucleation rate and reduce the rate of grain growth, which is helpful to refine the grains of alloy.