Research Of Semi-solid Forging Forming For Aluminum Alloy Wheel

By the trend of automotive lightweight, casting aluminum wheels have been popularized in the auto industry with its characteristics of relatively low price, good performance, beautiful appearance and so on. But forging aluminum wheels with complex production process and high cost are used in special areas such as sports car, as casting ones can no longer meet the performance requirements. Semi-solid forging is a near net shape technology, and the forming parts with this technology have close performance but lower cost to forging ones and more effective than casting ones in lightweight, so it has an important meaning to apply this technology in the production of automobile wheels.Semi-solid forming technology, numerical simulation, A356alloy have been introduced in this paper, and the advantages and prospects of the application of semi-solid forging with A356aluminum alloy in the production of automobile wheels have been described. In the experimental parts, the structure characteristics of the semi-solid A356alloy was studied; Using FLOW-3Dsimulation platform, the characteristics and variation of metal flow,and then semi-solid forging experiments to determine the appropriate forming process; Finally, the influence of solution temperature and aging temperature on microstructure and performance of forming parts were studied to define the heat treatment process, and a verification experiment conducted. The results are as follows:The semi-solid forging forming process of A356alloy was studied using numerical simulation based on semi-solid A356alloy apparent viscosity model.The characteristics of melt flow and temperature distribution were obtained by analyzing the effects of extruding speed, semi-solid slurry temperature and mould preheating temperature on semi-solid forming performance of aluminum alloy wheel. As the results shown, the optimal forming process of alloy wheels was concluded.The main process parametersof affectedsemi-solid forging was:the filling speed, filling temperature, mould preheating temperature, pressure and thepressuretime. By comparing the experimental validation of a set of the best semi-solid wheel forging process parameters were as follows:filling temperature is600℃, the extruding speed is5.0mm/s,the mould preheating temperature is300℃,the extrusion pressure is2160kN, the dwell time is25s.The solution and aging heat treatment process as follows:the solution temperature is535℃and the time is10h; the agingtemperature is 167℃and the time is6h. The tensile strength after the heat treatment is322.7MPa and the extension rate is7.17%.