Comparative Research on Hot Compression Behavior of Mg-5Sm-(3,4)Gd Alloys
The hot compression tests of the as-cast Mg-5Sm-3Gd alloy and Mg-5Sm-4Gd alloy were carried out by using a Gleeble-1500 thermal simulation test machine at deformation temperature of 350-500 ℃ and the strain rate of 0.01-1 s-1.The critical strain and peak strain of dynamic recrystallization were determined.The constitutive equations and the hot processing maps of alloys were established.The results show that the flow stress curves of these alloys have obvious dynamic recrystallization characteristics.Under the same conditions,the peak stress and flow stress of Mg-5Sm-4Gd alloy are higher than those of Mg-5Sm-3Gd alloy.The critical strain for dynamic recrystallization is almost half of the peak strain.The critical strain of recrystallization can be reduced by increasing deformation temperature or decreasing strain rate.The increase of Gd content increases the activation energy of thermal deformation and slows down the occurrence of dynamic recrystallization,but the hot processing maps of the alloys are basically the same.
万方数据
维普
