Study Plastic Deformation Behavior And Deformation Mechanism Of AZ31B Magnesium Alloy On Complex Stress

Magnesium alloys have great development potential as "green metal structural materials" in the 21 st century.However,the slip system of magnesium alloys is seldom due to the HCP structure which cause the poor deformability.The Schmid factor of complex stress needs more studies.Aiming at Schmid factor model of complex stress state,the Schmid factors of different deformation systems are reconstructed in Euler space in this paper.It provides a theoretical basis for the selection of deformation mechanism.According to the rolling stress state,the distribution of Schmid factor in Euler space is calculated.The results show that the initiation range of each deformation mechanism is very wide,especially the extension twinning.However,the maximum Schmid factor is obtained in different crystal orientations.So the selection of deformation mechanism will inevitably be priority or lag.Combining with the critical resolved shear stress,the set-up probability of basal slip and extension twinning initiation is higher.In addition,the Schmid factor is affected by crystal orientation and rolling parameters.The Schmid factor increases with the decrease of rolling diameter,reduction and the increase of plate thickness.However,the thickness of sheet metal and the diameter of roll have little influence on the deformability.So rolling reduction can be used to change the deformability.The plastic deformation behavior of AZ31 B magnesium alloy under different rolling processes is also studied in this paper.The results show that the hot rolled AZ31 B magnesium alloy has strong basal texture.The cold rolled can weaken the basal texture of AZ31 B magnesium alloy.The Schmid factor of basal slip in the direction of ?=45° degrees is larger when the reduction is small.Due to the large Schmid foctor basal slip are easier to charge crystal orientation.When the reduction is large,the Schmid factor of the extension twinning of ?=80° grain is larger.It is easy to deform,change crystal orientation,and promote the initiation of basal slip.But the deformation system is start in both directions whether the reduction is large or small.In this paper,some twinning variants are calculated and the calculation results of starting twinning variants is(1-102)[-1101].The Schmid factor of the basal slip system increased after the twinning initiation.