Study On Extrusion Forming Technology Of 7A04 Aluminum Alloy Wheel With Deep Trough

The traditional heavy vehicle wheels with deep groove are usually made by welding andassembling with Q235,which is heavy weight and poor mobility.This kind of wheels hasdisadvantage of high fuel consumption.As energy sources are depleting,the government beginto emphasize energy-saving and environment protection.On this premise ,the traditionalmaterials and forming processes can’t satisfy with the policy of Equipment Lightweight.Thispaper focus on the whole extrusion process of 7A04 aluminum alloy wheel，instead of Q235steel.Because the cross-section structure of this wheel is so large and complex, the simulationshow that the load of direct forming is very large,which seriously affects the life of themold.This paper focus on reducing load and optimizing forming situation.Based on theprincipal stress method,we reduce the simulation load by punching and reaming with coremold.The load of bottom extrusion is reduced by the applications of constrained divided-flowtechnique;We optimize the load and the forming of retaining ring part by adding flaringprocess when flanging the workpiece.Because there is deep groove in this wheel,whichincrease the difficulty of forming process.The invention of the auxiliary semi-mold only solvethe problem,but also saves the cost of mold.We finally determine the process：preformingâ†'punchingâ†'reaming with core moldâ†'backward extrusion straight armâ†'bottom formingâ†'flaring and shrinkingâ†'flanging.We eventually succeeded in the trial by the existing experimental equipmentconditions.The performance test results show that tensile strength and yield strength of thewheel made by new process raise to 580.7MPa and 511.2MPa,the elongation percentage andthe product of strength and plasticity reaches 11%.Compared to traditional wheels,the performance of the new ones is obviously promoted，and its weight is also reduced.Test trialresults show that the final process are reasonable and the designs of the mold structure arefeasible.It provides important guidance for similar cylindrical parts with deep grooves.