Research On Sensitivity Of Spinning Forming Parameters Of Internal And External Toothed Parts Based On Response Surface

Internal and external toothed parts（IETP）are the core components of the dual clutch transmission.The internal and external toothed structure plays an important role in the transmission of torque,and it bears greater impact load in the working process,so it has higher requirements on its strength,stiffness,dimensional accuracy and interchangeability.Spinning is a kind of precise near net plastic forming technology.During spinning,the fiber direction of metal is adapted to the product shape.Therefore,spinning can realize the high precision and high performance precise forming of IETP.However,due to the specific deformation of the sheet metal during the spinning process,IETP are easy to have such defects as uneven wall thickness on the tooth side,asymmetric tooth angle on both sides and springback along the axial direction of the tooth surface.The parameters that affect the forming quality of IETP include not only the spinning process parameters,but also the structure parameters of the die with teeth.The primary and secondary relationship and interaction of the parameters on the forming quality of IETP are not clear.Therefore,it is of great theoretical value and practical significance to study the sensitivity of spinning forming parameters of IETP and quantitatively evaluate the influence of forming parameters on spinning forming quality.In this paper,the outer hub of a dual clutch transmission with internal and external teeth on the side wall is taken as the research object.Based on ABAQUS/explicit platform,the finite element model of spinning process of IETP is established.The reliability and accuracy of the finite element model are verified by energy ratio and forming process tests.Based on the finite element simulation results,the stress-strain distribution,material deformation characteristics and the variation of spinning quality were analyzed.The results show that the middle of IETP is in the plane strain state,the material is compressed along the radial direction and elongated along the circumferential direction,but there is almost no flow in the axial direction.The mouth skirt and bottom flash of the part are in compression strain state,and the material is compressed along radial direction,elongated along tangential direction and axial direction.The deformation of IETP has three characteristics:the periodicity of deformation distribution,the non-uniformity of circumferential and axial deformation,and the asymmetry of tooth sidewall deformation.The wall thickness of tooth and tooth angle of IETP are evenly distributed along the axial direction,and the contour diameter of IETP increases linearly along the axial direction,which leads to springback.On this basis,the optimized Latin hypercube method was used to design the experiment,and the polynomial response surface model was constructed based on the data obtained from the finite element numerical simulation;the influence of the forming process and die structure on the forming quality was studied by Sobol sensitivity analysis method,and the sensitivity of the forming quality to the forming parameters was obtained.The results show that:in the forming process parameters,the clearance between the roller and the mandrel is the main influence parameter of the wall thickness of tooth,the springback angleαandβof tooth surface;the number of shaping cycles q is the main influence parameter of the tooth angleδ;the speed of the mandrel n and the feed speed of the roller v_fonly affect the tooth angleδ.In the structure parameters of die,the root circle diameter of the mandrel d_fmis the main influencing parameter of the diameter deviation△d_ai and△d_fi of internal teeth profile,the springback angleαof the tooth top surface and the tooth angleδ;the inclination angle of tooth root surfaceα_m is the secondary parameter affecting the tooth angleδand the main parameter affecting the springback angleβof the tooth root surface.The inclination angle of tooth top surfaceα_m has little effect on the diameter deviation△d_ai and△d_fi of internal teeth profile.Based on the polynomial response surface model and sensitivity analysis results,a multi-objective optimization model of forming parameters was designed,and NSGA-II algorithm was used for optimization analysis.The results show that the optimal combination of process parameters is as follows:the clearance between the roller and the mandrel is1.84mm,the times of the mandrel reversing is 3,the speed of the mandrel is 97.943r/min,the number of shaping cycles is 9.521,and the feed speed of the roller is 1.899mm/s.The optimal combination of structure parameters of die is as follows:the inclination angle of the tooth top surface of the mandrel is 1.326°,the inclination angle of the tooth root surface of the mandrel is 1.241°and the diameter of the tooth root circle of the mandrel is 119.192mm.The wall thickness and profile diameter of the tooth of spun workpieces meet the requirements of dimension tolerance of IETP.