梯形轮廓曲面件多夹钳拉形的成形力研究

Research on forming force of multi-gripper stretch forming for trapezoidal profile curved part

为了研究成形力对三维曲面件拉形质量的影响,采用有限元软件ABAQUS,以梯形轮廓曲面件为研究对象,建立梯形毛坯的多夹钳拉形有限元模型,选取4组不同的成形力进行数值模拟。结果表明:水平拉力一定时,随着倾斜拉力的增加,成形件的应力和厚度分布更均匀,但是进一步增加倾斜拉力时其分布均匀性变差;倾斜拉力为水平拉力的3/4时成形效果最佳,且成形件的回弹量较小,分布也较均匀。采用该成形力在多夹钳拉形机上进行了梯形轮廓曲面件拉形试验,成形件的质量良好。试验结果与数值模拟结果一致,验证了梯形毛坯多夹钳拉形的可行性和数值模拟的正确性。

In order to study the influence of forming force on the stretch forming quality for 3D curved parts,for the trapezoidal profile curved part,the finite element model of trapezoidal blank in the multi-gripper stretch forming was established by finite element software ABAQUS,and the stretch forming process was numerically simulated by selecting four groups of different forming forces.The results show that when the horizontal stretch force is constant,the distributions of stress and thickness for formed part are more uniform with the increasing of oblique stretch force,but the distribution uniformity becomes worse when the oblique stretch force is further increased.However,when the oblique stretch force is three-quarters of the horizontal stretch force,the forming effect is the best,and the springback amount of the formed part is smaller and the distribution is more uniform.Using this forming force,the stretch forming experiment of trapezoidal profile curved part was conducted by the multigripper stretch forming machine,and the formed part had good quality.The experiment results are consistent with the numerical simulation results,which verifies the feasibility of the multi-gripper stretch forming for trapezoidal blank and the correctness of numerical simulation.