Numerical Simulation Of Compression Forming For Iron-based Powder Metallurgy Synchronizer Cone Ring

Synchronizer cone ring is a key component on heavy-duty automotive transmissions and is a multi-step complex structural component.At present,the domestic synchronizer cone ring is mostly manufactured by casting process or alloy steel machining process.Using powder metallurgy technology instead of traditional casting and machining technology to produce synchronizer cone rings has the advantages of high material utilization,uniform structure,high manufacturing accuracy,light weight and wear resistance.At the same time,it greatly reduces production costs and improves production efficiency.Aiming at the numerical simulation analysis of the key process “press forming” of the iron-based powder metallurgy synchronizer cone ring,optimizing the forming process parameters is of great significance for improving the quality performance of the synchronizer cone ring and accelerating the practical application of the product.The theoretical research on the technology of synchronizer cone ring press forming technology is carried out.The force and forming compact in the process of presser ring press forming are analyzed.The size of the main forming die of the synchronizer cone ring is calculated and synchronizer cone ring forming die and formwork structure are designed.The numerical simulation of the synchronizer cone ring press forming is carried out by the finite element numerical simulation software Deform-3D,and the numerical simulation software forming module is corrected.The Poisson’s ratio and elastic modulus of the synchronizer cone material are measured and selected,and the material model is established.Through numerical simulation of synchronizer cone ring forming,the density distribution of synchronizer cone ring,the change of die stroke load and the load change of demoulding process and under different pressing modes are analyzed.The press forming method is determined.The changes of relative density of the cones of the synchronizer and the pressing force of the cone ring blanks under different pressing speeds are analyzed,and the forming speed is determined.Through the orthogonal optimization,the four most important factors affecting the friction ring forming of the synchronizer,the mold floating amount,the pressing speed,the friction coefficient and the dwell time are weighted and ranked,and the weights of each factor are determined with the use of the analytic hierarchy process.For the "mould float amount" factor with the largest weight,four synthesizer cone ring forming process parameters are developed to compare and analyze the numerical simulation,and the optimal synchronizer cone ring forming process parameters were determined.The main research results in this paper are as follows: The structure of the main die and the upper,second and lower three die holders for the compaction forming of the conical ring of synchronizer is designed,and the dimensional accuracy of the main die is determined.The free floating of the die for the upper die,the negative die,the central mandrel and the circular tile is reached.The hardware support has been provided for the uniform distribution of the upper and lower steps and the overall density of the conical ring of synchronizer.The Deform-3D is used to simulate the simple ring bushing powder metallurgy parts,and the constitutive relationship and the effectiveness of the Deform-3D forming module are verified.The numerical simulation of the synchronizer cone ring shows that the uniformity of the floating press forming density of the synchronizer cone is better than that of the unidirectional pressing method,and the better press forming speed of 3 mm/s is favorable for uniform density.Through the orthogonal optimization,it is determined that the "mold float amount" factor has the greatest influence on the presser forming of the synchronizer cone.Four different forming process parameters are developed for the factors affecting the forming maximum weight.Through numerical simulation and comparison analysis,the optimal forming process parameters of the synchronizer cone ring are determined as follows: the upper die punch 2 float amount 7.5mm,the tile float amount 16 mm,the female mold floats synchronously with the central core rod.The optimal process parameters obtained by the simulation surface data analysis by the response surface method are basically consistent with the numerical simulation optimization parameters.The practical production proves that the numerical simulation optimization of the synchronizer cone ring forming process parameters can guide the practical production.