Research On Multi-step Spinning Process For Disk-like Parts With Thicken Rim

With today's socio-economic globalization,information is becoming more and more transparent,and manufacturing competition is intensified.Some disc-shaped parts with unequal thickness made by welding and machining have lost their competitive advantages,it is ergent to develop a new forming process,to meet to the market needs for lightweight,low cost,high-quality structural parts and components.Plate forging forming is an important means of producing unequal thickness parts to meet the requirements of lightweight parts.But limited by the forming force,the existing plate forging forming technology is only applicable to the size of the small parts.It is difficult to solve the forming problem of unequal thickness parts with large diameter used in automotive,aerospace and other fields.In recent years,some scholars have proposed a new forming process,thicken the edge of disc-shaped through spinning,but many details are not yet perfect.Therefore,this paper studies the new process of sheet metal forming with multi-step spinning thickening.The principle is that the upper platen and the lower platen press the circular plate at the same time and rotate at high speed together.The roller feeds the edge of the plate along the radial direction so that the material flows radially inward until the wheel Contact with the edge of the plate to achieve formed part with thicken edge.In this paper,multi-step spinning process is designed.Through simufact finite element simulation,the forming process,the flow law of metal in the process is studied.the influence of parameters of the rotor size to forming stability,filling and streamline distribution is analyzed,besides,the size of the wheel is optimized.Through the experiment,the feasibility of the optimized forming scheme is analyzed.And the flowline in the cross section of the formed part was observed by metallographic test.In addition,the hardness distribution in the cross section of the formed part is studied,and the reason is discussed.The forming process shows that during the forming process,the metal of the disc is flowing along the radial direction and flows along the tangential direction of the disc,thereby thickening the edges of the disc.In the 1st step,if R₁ is too large,it will lead to the fold in the edge of the formed part.If?₁ is too small,it will occur instability.If?₁ is too large,it will lead to serious bending streamline in the edge of the formed part.In the 2nd step,R₂,?₂,l₁ will have a great impact on the stability of the formation,and?₂ has impact on the streamline while R₂ and l1 have little impact.In the 3rd step,l₂ has a great impact on the forming stability,and R₃,?₃,has a little impact on the stability and flowline.In the final forming stage,the forming step number has an influence on the filling of the formed part.Finally,the feasibility of the finite element simulation results is verified by experiment.The results show that the flow lines in the cross section of the formed parts are distributed along the shape of it.the hardness distribution in the cross section is meaured,it shows that the hardness in the middle and the edge of the part are highest,and other places,showing the more close to the edge the greater hardness,the study found that it is resulted by uneven deformation.