Hot Compression Deformation Behavior and Processing Maps of Mg-Gd-Y-Zr Alloy

摘要

Hot compression deformation behavior and processing maps of the Mg-Gd-Y-Zr alloy were investigated in this paper. Compression tests were conducted at the temperature range from 300 to 450℃ and the strain rate range from 0.001 to 1.0 s~(-1). It is found that the flow stress behavior is described by the hyperbolic sine constitutive equation in which the average activation energy of 251.96 kJ/mol is calculated. Through the flow stress behavior, the processing maps are calculated and analyzed according to the dynamic materials model. In the processing maps, the variation of the efficiency of the power dissipation is plotted as a function of temperature and strain rate. The instability domains of flow behavior are identified by the maps. The maps exhibit a domain of dynamic recrystallization occurring at the temperature range of 375-450℃ and strain rate range of 0.001-0.03 s~(-1) which are the optimum parameters for hot working of the alloy.