Theoretical And Experimental Study On The Filling Process Of Injection Molding Micro-Channels

With the rapid development of MEMS technology, the miniaturization of heat exchanger is concerned. People not only try to improve the efficiency of the radiator, but also pursuit the practicality and economy of heat exchanger. Micro heat exchanger with small micro-channels has a wide range application. Plastic micro-channel heat exchanger will become a new research in the future. Polymer micro-injection molding technology make it possible to bulk copy complex microstructure, with new materials coming up, micro molding must have great prospects.This paper presents a micro-channel heat exchanger compositing of polymer and aluminum material, the numerical simulation results shows its excellent heat transfer effectiveness. It has a high feasibility. The influence of different dimensions, fin aspect ratio, draft angle, gate size and gate distribution patterns on filling and fin warpage was investigated by analysing a number of micro-flow injection mold flow models. Using CAE to design the mold of micro heat exchanger and optimizing the mold gate, flow runners and the cooling water channels. Metal-plastic composites injection molding process was studied by mold flow simulation, Contrast the molding effect of micro heat exchanger with or without the embedded aluminum sheet.Combined with the results of CAE analysis, using a two-cavity mold, single-gate runner systems, design micro-injection mold and produce it. Utilizing CNC milling machines and other equipments to stack mold core block and manufacture inlay aluminum.Based on orthogonal experimental design method, micro injection molding process of micro-channel heat exchanger is studied. From the experimental data analysis to get the impact of process parameters on the micro heat exchanger forming mass, density, warpage and other indicators, and obtain its optimum process parameters.The numerical simulation and experimental results show that the polymer-metal composite micro heat exchanger has good heat transfer ability, can meet cooling needs of electronic products. Location of the gate on the distribution of warping deformation is not obvious, increasing the micro-channel size and aspect ratio were significantly increased warpage. The result of filling micro heat exchanger was great effected by the size of the gate and the main channel, so do the volume shrinkage. Embedded aluminum can lighten the volume shrinkage and reduce the overall warpage.