异速比对镁合金板材轧制成形的影响分析

Analysis of the Effect of Differential Speed Ratio on Rolling Forming of Magnesium Alloy Sheets

基于Deform-3D软件对AZ31镁合金同径同速轧制和异速比为1.1、1.2、1.5、1.7的轧制过程进行模拟,并对板材等效应力、等效应变、轧制力和边部破坏情况进行对比分析。结果表明:异步轧制中由于“搓轧”变形的影响,形成的附加剪切应力大大削弱了外摩擦对变形的阻碍作用。随着异速比的增大,最大等效应力和轧制力显著降低,等效应变增大,有助于降低对轧辊强度的要求及能量消耗,同时可以轧制更薄的产品。然而,随着异速比的增大,板材边部破坏严重。因此,在镁合金板材轧制中,最佳异速比一般不大于1.4.

Based on Deform-3D software,the rolling processes of AZ31 magnesium alloy sheets were simulated under the condition of the same diameter and same speed as well as different speed ratio of 1.1,1.2,1.5 and 1.7.The equivalent stress,equivalent strain,rolling force and edge damage were also analyzed contrastively.The results show that the additional shear stress caused by cross-shear deformation could weaken the obstruction behavior of friction.With the increase of speed ratio,the maximum equivalent stress and rolling force are reduced significantly,while the equivalent strain is increased.It is helpful to reduce the strength requirement of rollers and save energy.Meanwhile,it is successful to produce the thinner sheet.However,the edge damage is serious with the increase of speed ratio.Therefore,the optimum speed ratio is generally less than 1.4 in during the rolling of magnesium alloy sheet.