基于径向基函数近似模型的板料自由折弯成形回弹预测

Springback prediction of sheet metal free bending based on approximation model of radial basis function

为实现对钣材V形自由折弯的有效控制,首先建立了V形自由折弯卸载前上模下压量模型,并基于此理论模型在有限元分析软件ABAQUS中运用显示和隐式相结合的方法,对板材V形自由折弯成形与回弹过程进行有限元仿真。然后以板料回弹量为试验指标,以板料厚度、板料弹性模量、上模圆角半径和下模开口宽度为影响因子,每个影响因子取5个水平数,设计了正交试验。根据正交试验方案及结果,建立自由折弯板料成形回弹的径向基函数近似模型。通过仿真试验与实际折弯试验对模型进行了验证,回弹预测角度误差为±0. 8°,验证了方法的可行性,为下一步应用于自主研发的折弯机数控系统提供支持。

In order to realize the effective control of the V-shaped free bending of sheet metal,firstly,the press amount model of upper die before the V-shaped free bending unloading was established,and the processes of forming and springback of the V-shaped free bending for sheet metal were simulated by the finite element analysis software ABAQUS combining explicit and implicit methods.Then,the springback of sheet metal was taken as the test index,and the thickness of sheet metal,the elastic modulus of sheet metal,the radius of upper die roundness and the width of lower die opening were taken as the influence factors.Furthermore,the orthogonal experiment was designed by taking five levels of each influence factor.Based on the orthogonal experimental scheme and results,the approximate model of radial basis function for springback of free bending sheet metal was established and verified by actual bending experiment with error of springback prediction angle of±0.8°.Thus,the feasibility of the method was verified,which provided support for the further application of CNC system of self-developed bending machine.