| Gas-Assisted Injection Molding (GAM) is a new process introducing gas into conventional injection molding, with the advantages of low injection pressure, small warpage, high surface quality and good processing performances. Due to the introduction of gas, GAIM process becomes much more complicated than the conventional injection molding. Compared with conventional injection molding, GAIM satisfies some special requirements on product design, mold design, control of the process. Therefore, it is necessary to find a reasonable CAE analysis method for the application of CAIM. In this thesis, the CAE simulation was carried out to study the printer cover panel. Through studying the key technologies such as the gas-channel design and parameters design, the processing parameters and the product quality was forecasted. In addition, the results from CAE analysis were verified during the practical process and it had a good guiding effect on the practical produce.For gas-channel design which is the most crucial aspect of CAIM, the orthogonal test with three factors and three levels was carried out and then the sheet accessory was simulated and analyzed by using CAE software MPI to study the effect of gas channel design parameters on gas penetration. It was demonstrated that the equivalent radius of gas channel had a greatest influence on gas penetration and the length of gas penetration was mainly impacted by shape factors. In addition, the length of gas channel had an important effect on the degree of filling.It becomes difficult to design the processing parameters for CAIM in respect that the processing parameters vary with gas penetration easily. During the simulation experiments, the five most important processing parameters (short-shot size, gas delay time, gas pressure, and melt temperature) were treated as five different factors, respectively. The orthogonal test with five factors and two levels was carried out on each factor for two times. Through the experimental analysis, the effect of each factor on the confectioning was obtained and the interactions among the different factors were evaluated. Based on the experimental results, it was concluded that the lengths of gas penetration was influenced mainly by melt pre-injection volume, gas pressure and gas delay time. It was found that besides melt pre-injection volume, gas pressure and gas delay time, the gas pressure and melt temperature had interacting effects through analyzing the thin-wall-penetration.The technology of printer cover panel produced by CAM was designed and the design process was simulated by CAE software MPI according to different schemes in order to obtain the best process design. According to the results of gas channel design and the effect picture of gas penetration from the CAE simulation, the ideal gas penetration was obtained based on the conventional design. In this scheme, the size of gas channel is smaller and the gas channel has a better gas penetration effect. Considering the requirement of the practical produce, the parameters were optimized based on the results of the orthogonal test. Through comparing different parameters, the optimized processing parameters were obtained by using CAE analysis. It was shown that CAE simulation results can forecast process design and product quality.Comparing the forecasting results and practical technological design, it can be seen that the CAE simulation results can forecast the confectioning process in the range of error reasonably. In conclusion, the gas delay time was a little longer and the gas delay pressure was a little larger than that of the real process, respectively. The processing parameters such as the gas penetration, the remnant wall thickness of the products, process equipment, the temperature parameters and the injection time can be forecasted successfully by CAE simulation. The simulation of residual wall thickness is deferent with the actual results. This problem is found around the gas injection port.
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