Study On Forming Quality For Outer Flanging Process Based On Numerical Simulation

In the actual production of the past, both of the shape and size of the outer edgeflanging parts rely on experience and trial method.But these methods required the cycle test,so it often caused a lot of manpower and material resources waste. Another,the shape andsize of the blank emerged out a lot of deviation and also could cause forming bad problems,such as the bottom of the parts were not in the same level around the lower end of thevertical edge and on both sides of the vertical edge were inward tilt.According to the needs of studying, using ST15manufacture blank as the researchobject, blank central angle is180°, edge radius is12mm, outer radius is60mm, flangingcurve radius is32mm and width of flanging blank is20mm.Based on the numericalsimulation technology and the finite element software Dynaform platform, it analyzes thecurved edge flanging forming process and reveals the causes of poor formability.Under different blank holder force, the consistency of both numerical simulation andthe physical experiment results showing that the established finite element model isreasonable.By comparing the curved edge flanging and round hole flanging forming, it showedthe distribution characteristics of equivalent stress,tangential stress, equivalent strain and tangential strain.The results showed that the flangingof the shaft to the outer edge of parts (and vertical edge on both sides of the edge Angle area)occured only elastic deformation. As the blank-holder force increasing, phenomenon ofinward tilt of the vertical degree and vertical edge on both sides of the edges of the bottomwas decreasing.When the blank-holder force increased to a certain extent,on the one hand,parts forming quality tends to be stable and no big changes;on the other hand withoutcausing deformation of deep drawing whatever blank-holder force change. The basis of thevertical edge on the bottom of the projection angle and vertical edge on both sides of theinward tilting, the bad forming phenomenon still exists. By adjusting the blank holderforce,it cannot reach the purpose of eliminating the bad parts forming.As the blank sideedge in free state, the stress and strain distribution in each region of the parts, the straindifferences is the main cause of the bad parts of flange flanging forming.This paper come to a conclusion that by reducing flange width in different areas of theblank with the aim to eliminate parts out of the edge to the bottom of the projection angle;By increasing the blank size of the two sides to improve to form a vertical edge on bothsides of the the phenomenon of inward tilt and it could improve the quality of flanging forming parts. By improving the component forming situation, based on revising the shapeand size to improve the uniformity of metal plastic flow and average strain gauge waspresented.As the strain gauge, it reversed different width of flanging blank in different areas ofthe blank, made cycle simulation and repeatedly modified blank shapes and sizes, in orderto get flanging forming good parts. Through the test, it verified the reliability of the methodand provides the certain reference significance for practical production.