The Numerical Simulation And Process Parameters Optimization On The Combined Forming Of Fine Blanking Of The Copper Heat Sink

The technology of the combined process of fine blanking is a new technology of Sheet metal parts forming developed in recent years, which is combined of the fine blanking and the bulk forming. It can implement the production automation on fine blanking press. The technology substitute the traditional crafts, such as casting, welding, cutting, die casting, and increase production efficiency, reduce subsequent processing operation. This thesis researches the best process parameters of a type of copper heat sink.Through structural analysis of the copper heat sink, combined with the feature of extrusion and blanking, this thesis proposed the process plan that firstly extruding the boss, then blanking hole. First of all, formation of this part's boss is extruded by thickening thin plane. Through setting aggregating boss, when plunger die screw down, the material cause divided flow. Some of material flow into fin groove, and others which form thickening boss flow into die cavity, so it can realize the aim of thin plane forming thick parts. This plan compares to the plan of thick plane have two advantages. On one hand, it lower stress of parts and improve die life, on the other hand, it can reduce the sheet thickness and enhancing utilization rate of material. By means of special finite element soft ware DEF0RM-3D, simulating this plan find the minimum thickness of the part. The holes of part use forming process of plate fine blanking. Through simulation experiment and theoretical calculation, the process parameters of fine blanking, such as blank hold force, anti force, fine blanking clearance and fillet radius of convex and concave die, are obtained, and those proper parameters can get the part which meets the design requirement.Forming this part need more work station, so proportionality of load of each forming work station must be considered, therefore the process parameters of combined forming of fine blanking, including number of work station, reduction amount of each work station, height of aggregating boss, should be optimized. In order to optimize the combined process of fine blanking, orthogonal design is adopted to make experiments, and each plan has been simulated. Mapping relationships between the optimized parameters and the total of forming load and the range of forming load are obtained by BP neural network training which set the optimized parameters as the input variable and take the each simulated result as output value. Though the multi-objective genetic algorithm, the process parameters are optimized. Experiment of optimization result indicate that proper design parameters can make the total of forming load and the proportionality of the distribution of forming load better.