Study On Springback Of Flexible Sheet Metal Forming Process

Stamping incremental forming is a new type of flexible manufacturing technology.Compared with the traditional forming process,the forming force of the stamping incremental forming process is significantly reduced,so it has great application potential in the manufacturing industry.At present,the research on this forming process is still in its infancy,and there are many basic research needs to be carried out.Springback is one of the most important parts.Springback is an important factor affecting the forming accuracy of sheet metal.Due to its high nonlinearity influenced by many factors,no good solution has been found in numerical and analytical methods to solve the springback problem.Especially in 3D freeform surface in the study of flexible forming of sheet metal processing,domestic and foreign research on the springback is very limited,and they didn’t consider different loading paths on the influence of complex sheet metal bending springback is proposed.This paper bases on the stamping incremental forming technique proposed by the program group and depends on the two sets of machine tool designed by the program group.On the basis of current researches,the paper takes the combination of theoretical analysis,multivariable shaping springback experiment and data stimulation as the method.Then,it studies the springback influence by loading path and the springback regulation of sheet metal during the forming process.Then we built the prediction mode to predict the springback.The major research results are showed as follows:(1)The springback theory of sheet metal is studied systematically,and the numerical simulation model of incremental forming process is constructed and verified by experiments.At the same time,the effect of support and the gravity of the plate is considered in the springback process,which ensures the realization of continuous simulation of multiple stamping.(2)Based on the experimental and numerical simulation methods,the influence of loading path on the stamping load and springback of the one-way plate was studied.The closer the stamping position is to the support,the greater the stamping load and the smaller the springback.The larger the supporting distance,the smaller the stamping load and the larger the springback.(3)Based on the experimental and numerical simulation methods,the influence law of the loading path on the stamping load and springback of the two-way plate is studied.Studies have shown that the forming rules of two-way plates and one-way plates are significantly different,and the stamping position has a significant influence on the maximum load and springback during the single-point stamping process of the two-way plate.Therefore,it is necessary to consider the real deformation and springback of plates at different stamping positions when machining two-way plates.(4)The BP neural network algorithm and fuzzy neural network algorithm are used to directly predict the springback amount of the plate,and a new method for predicting the springback amount is provided for the dieless incremental forming.(5)The electro-hydraulic forming process,which is a method for reducing the springback amount of the sheet,has been studied,and has great application potential in some fields requiring complex precision parts.