Profiles’ Stretch-bending Research Based On Secant Iterative Compensation Mechanism

As one of the important forming process in,products by making use of stretchbending have advantages of good surface quality,high accuracy,little springback,etc,and are wildly used in the fields of automotive,aviation,aerospace,shipbuilding,etc.The springback phenomenon in the process of unloading often affects the precision and surface quality of the stretch-bending parts,therefore,it is necessary to study the springback law and find an effective method to improve the quality of the stretch-bending parts.In recent years,many domestic and foreign experts use various means to control or predict the springback,and although many scholars in different bending process and bending model proposed different solutions,these methods are mostly just a rebound control of one or a kind of model,which is not universal.This paper proposes a generalized iterative compensation mechanism to approximate the target expectation,from the theory,simulation and experimental multi-angle to verify the feasibility of this method.Started from the experimental results of the 08 AL free bending,inspired by the idea of continuous mold repair in practical engineering,combined with the thought of equation iterative extracting a root coming from a book named Numerical Analysis to explain iterative compensation in the process of blending springback,according to the thought of secant method accelerated iteration for root to explain pringback problems and prove it’s convergence,as well as to prove that the convergence of the sheet metal under bidirectional tensile deformation when the length is an iterative parameter.The finite element model of the rocker arm stretch-bending machine is established by the finite element simulation software ABAQUS,iterative compensation methods of difference method and secant method are simulated respectively through two types of mold surfaces with different curvatures.Comparing the advantages and disadvantages of the two iterative methods,simulation results show: secant method iterative compensation has quicker convergence rate.It is verified by experiments that the Iterative Compensation Mechanism of secantmethod converges faster than difference method’s.The iterative compensation experiments of difference method and secant method were carried out under the condition that the properties of brass H59 don’t be measured to show the generality of Iterative Compensation Mechanism of difference method and secant method.