Low Temperature Laser Thermal Forming Technology Of Metal Sheet Under Prebending

For a long time,the metal sheet forming parts in the machinery manufacturing industry(including shipbuilding,automobile manufacturing,aerospace,agricultural machinery manufacturing,etc)have been a large proportion,many varieties,and the forming process is complex.It is necessary to produce a large number of high temperature resistant moulds with high cost and long cycle in the whole plate mechanical stamping process.Some parts are too large for mechanical stamping.The traditional laser heat forming method often requires high power laser,which greatly improve the processing cost.The method can produce high temperature on the surface of metal sheet during processing,which greatly damages the original microstructure and mechanical properties of metal materials.In this paper,the metal sheet laser thermal forming at low temperature under the action of the prebending is studied on the basis of the traditional laser thermal forming.This forming technology with high efficiency and low temperature retain the original microstructure and mechanical properties of sheet metal.This article used the ANSYS finite element analysis tool,on the basis of the large deformation elastic-plastic finite element theory,indirect thermo-mechanical coupling nonlinear analysis method,finite element analysis model was set up,used powerful post-processing function of ANSYS to analyze the simulation results.Used a single variable method,explored the condition of temperature field and stress field of the sheet metal scanning,the change rule of sheet metal bending angle,the maximum deformation change rule before unloaded prebending,the change rule of metal sheet springback angle after unloaded prebending in the condition of different laser processing parameters,different size and direction of prebending and scanning position.Explored the comprehensive energy factors on temperature field,deformation field,metal sheet bending angle,maximum bending angle,metal sheet springback angle after unloaded presbuckling.Used orthogonal experiment method to confirm the influence degree of each energy factors,and given optimal process parameter planning.To meet the needs of practical production,explored the influencen of laser scanning frequency and time interval in each scanning on plate temperature field,stress field,metal sheet bending angle,plate maximum bending angle before unloading prebending and metal sheet springback angle after unloading prebending.