Study On The Law Of Springback Deformation Of Multi-point Formed Parts By Trimming

As one of the main processing methods of metal three-dimensional curved parts,stamping forming process is widely used in modern manufacturing.The process which puts pressure on the metal sheet to make it plastic deformation and get the target shape.Due to the characteristics of processing and metal deformation,springback has become the most important factor affecting the precision of stamping parts.Therefore,the research and solution of the springback problem is of great significance to improve the forming accuracy of stamping parts.At present,the research and control of springback in the sheet metal stamping forming process are mainly focused on the springback after the stamping die is unloaded.As an indispensable process in the stamping process,the trimming has less research on the springback deformation of stamping parts.Actually,it shows that the shape of part has changed after trimming(cutting off the excess sheet material on the periphery),that is,trimming springback has occurred,which reduces the forming precision of the part.Therefore,it is of great significance to study and control the springback deformation after trimming to improve the forming precision of the part.This paper analyzes the laser trimming process of spherical parts formed by multi-point forming,and obtains the influence of different forming parameters on the springback deformation of spherical parts after laser trimming.The influence of different cutting paths on the springback of spherical parts during laser trimming was analyzed,and the path optimization was performed.The method of springback compensation for stamping parts was obtained,which took the trimming springback into consideration.The specific research contents and conclusions are as follows:(1)Numerical simulation method was used to design the simulation process of laser trimming process of spherical parts,and a finite element simulation model of laser edge trimming of a multi-point formed spherical part was established.The key issues of the laser trimming simulation process of spherical parts were dealt with,including the establishment of laser cutting heat source model,the selection of heat source model,the removal of material at the cutting seam during cutting,and the realization of laser heat source movement.(2)The effects of plate thickness and radius of curvature on the springback deformation of the laser trimming process of spherical parts were analyzed by numerical simulation methods,and the conclusions of the simulation were verified by experiments.It is concluded that the springback deformation of the spherical part during laser trimming decreases with the increase of the plate thickness,and the degree of decrease in springback also decreases as with the increase of the plate thickness;With the increase of the radius of curvature,the trimming springback of the spherical part during the laser trimming process gradually decreases.(3)Three kinds of cutting paths for laser trimming of spherical parts were designed,and the effects of three different cutting paths on the rebound deformation of laser trimming of spherical parts were analyzed through simulation.The third kind of cutting path(First cuts each cutting boundary of the square cutting path in half,and finally cut one by one)has the least influence on the springback deformation of the laser trimming process of the spherical part.Finally,the conclusion of the simulation was verified through experiments,and the cutting path of the laser trimming process of the spherical part was optimized.(4)Aiming at the problem that the spherical part has a large springback after laser trimming,which seriously affects the forming accuracy of the part,the method of springback compensation was studied.Finally,compensating the forming surface of multi-point basic body group was determined to compensate the springback of parts.