Study Of Gas Penetration Behavior In Gas-Assisted Injection Molding

Gas-assisted injection molding (GAIM) is a new technology based on traditional injection molding technology which is widely used because of it has been overcome many disadvantages of traditional injection molding technology during injection process. Following with technology development, method of gas injection and process becoming more complex which cause the effect of gas to product more and more complex. Therefore, it is necessary to do a thorough study on GAIM to guide production.The gas penetration behavior in Gas-assisted injection molding is studied. The experiments are performed in the different ribs and the actual product. The main work and conclusions of the paper as follows:1. Gas-assisted injection molding and the present research status at home and abroad is briefly introduced, puts forward the content which need to be further researched.2. The effect of processing parameters on gas penetration behavior was studied. The experiments are performed in the rib with semicircular gas channel section. The gas penetration behavior include: the length of gas penetration, residual wall thickness and secondary gas penetration which was few considered. And a further analysis and explanation is made.3. The effect of different plate width of ribs to gas penetration behavior is studied. The experiments are performed in the ribs of different plate width which is 50mm and 60mm. The orthogonal experimental design is used to get the optimization of processing parameters. The same and difference of the optimization results are compared and analyzed.4. The effect of different section shape of gas channel to gas penetration behavior is studied, which is based on the same processing parameters and the equivalent melt shot size. The study will provide the basis for design of gas channel selection in product.5. Using methods of the orthogonal experimental design, the gas penetration behavior in the rearview mirror products have been studied to get the optimization of processing parameters of the gas-assisted injection molding. Finally, in the experiments of the actual producing, there were several defects of product. By referencing the study of the orthogonal experiment in numerical simulation, the processing parameters were changed and the better product of no defect had been produced.