Research On The Incremental Forming Method Of Special-shaped Sheet Metal

Different forming methods in CNC(Computer numerical control)incremental forming will have different effects on the forming effect.Therefore,exploring different forming methods is an important part of CNC incremental forming.In research of CNC incremental forming,most research objects are sheet metal part with contour edge curve on plane.However,in the actual application of aviation,automobile or medical prosthesis,there are sheet metal part with contour edge curve in space.Since the contour edge is not curve on plane of sheet metal part,it is difficult to proceed directly with the incremental forming.A CNC incremental forming strategy for the sheet metal part with contour edge curve in space is proposed.In addition,aiming at the problem that stamping is difficult to form complex sheet metal,the stamping mold is difficult to manufacture or the processing cost is high,and the CNC incremental forming process alone is inefficient.A hybrid forming method combine stamping with CNC incremental forming is proposed.In the study of sheet metal with contour edge is a curve in space,the developed CAD / CAM software system is used to obtain the optimal datum plane of the model.Then filled the vacancy model into the model with contour edge in horizontal plane.After used the filled model to generate the required forming trajectory.Finally,generated CNC forming trajectory and support are used for the finite element analysis in the ANSYS and CNC incremental forming experiments in the machine,respectively.In the study of the hybrid forming method combining stamping with CNC incremental forming,three methods of stamping forming,CNC incremental forming and hybrid forming are numerical simulated respectively by finite element software of the same shape of sheet metal parts,and their shape precision and thickness distribution were comparatively analyzed.The results show that the proposed forming method can be used to form the sheet metal which the contour edges is irregular curve.Then the sheet metal have better shape precision and evenly thickness distribution.Besides,the shape precision and thickness distribution of sheet metal obtained by hybrid forming can meet the practical application,and the proposed hybrid forming method is feasible.