激光拼焊板渐进成形工艺与回弹控制研究

ABSTRACTOwing to the advantages of high flexibility,low-cost,low forming force and highform ability,incremental forming becomes one of the new sheet metal forming methodsin recent years,which is rarely applied to the research of the forming of lasertailor-welded plate.Laser tailor-welded plate has been widely used everywhere becauseof the ways it has paved for the automotive lightweight,energy conservation andemissions reduction,manufacturing cost reduction,improvement of vehicle safety,etcWith the increasing mature of laser tailor-welded plate and incremental formingtechnology,putting the incremental forming technology into the laser tailor-weldedsheet has becomes especially vital to the area of engineering.Studies found that both domestic and foreign using the incremental formingtechnology into the research laser tailor-welded sheet is not mature enough,there aremany issues to be resolved.Common defects in sheet metal of incremental formingprocess are:parts over the forming limit,surface quality defects and the low accuracy.Therefore,this article mainly discusses the forming limit and forming precision ofincremental forming in the laser tailor-welded plate.First,this paper introduces the present situation and development of sheet metalincremental forming in the world and the characteristic of the laser tailor-welded plate,as well as a method of weld model in the numerical simulation.Then,with the variableangle ellipse part as the research object,a tailor-welded plate finite element model wasbuilt by using FEM in view of the problem of forming limit.The impact on formingproperties of laser TWBS is researched by means of orthogonal experiment,what themain process parameters include tool diameter,tool depth,welding seam position andplate thickness.Finally,for the problem of springback during forming cone,researchingthe rebound problem of laser tailor-welded plate incremental forming by the numericalsimulation;verifying the validity of the finite element model through the experiment;using the method of neural network to establish the rebound prediction model.The result shows that:Incremental forming performance:Weld position is the main factors for sheet metalforming limit,followed by combination of thickness,tool diameter and tool depth;Weldperpendicular to the principal strain can ensure uniform deformation;Maximizing tool