气体辅助注塑在彩电外壳中的应用

APPLICATION OF GAS-ASSISTED INJECTION MOLDING TECHNOLOGY IN COLOUR TV CABINET

研究彩电外壳注塑和气体辅助注塑充模过程的计算机模拟和实际生产。应用动态应力流变仪测试材料流变性质,得到模拟所需n、B、τ、β、T_b等5个参数。考察熔体注射温度、注射时间、入口位置、材料性质对充模过程的影响,得到优化充模结果;还考察了气体辅助注塑过程熔体预注射量、气体注射压力对充模过程的影响。结果表明,气体辅助注塑成型新工艺采用三浇口,熔体适宜预注入量为95％,注射温度230℃,注射时间5s,用幂律指数n较小的聚合物。

In this paper, we studied the simulation and manufacture of colour TV cabinet by gas-assisted injection molding compared to injection molding. We tested the dynamic rheological properties of resins used and got parameters n 、 B、 τ 、 β Tb which used in simulation. The influences of melt injection temperature, injection time, gate location and materials property on the filling process were studied and the reasonable results were attained. And also, the influences of pre-injected resin volume and gas pressure on gas-assisted injection molding process were studied. The results show that three melt inlets are enough for melt filling. The optimum pre-injected resin volume is 95% , melt injection temperature is 230℃, nielt injection lime is 5 s. It is better to use resins with smaller power law index n.