In thin-wall injection molding, due to the very fast polymer melt heat transfer to the mold wall, the freeze layer appears quickly during the filling stage. In this study, high-speed injection molding (up to 1400 mm/s injection speed) was studied. A mold of spiral shape, 0.4 mm thick, is used to verify the ability of melt filling under different injection speeds. Simulation by Moldflow software was also performed for verification. The result shows that when injection speeds vary for 100 mm/s, 500 mm/s, 1000 mm/s, and 1400 mm/s, the flow length to thickness ratio was increased with the value of 335, 467.5, 605, and 640, respectively. The simulation results also show that the heat transfer coefficient between hot melt and mold wall has a strong influence on the flow length, especially with the high-speed injection molding. In general, slower injection speed requires a higher heat transfer coefficient, whereas higher injection speed require only a lower heat transfer coefficient.
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机译：在薄壁注射成型中，由于聚合物熔体的热量非常快速地传递到模具壁，因此在填充阶段会很快出现冻结层。在这项研究中，研究了高速注射成型（最高1400 mm / s的注射速度）。使用0.4 mm厚的螺旋形模具来验证不同注射速度下熔体填充的能力。还通过Moldflow软件进行了仿真以进行验证。结果表明，当注射速度变化100 mm / s，500 mm / s，1000 mm / s和1400 mm / s时，流动长度与厚度之比增加，数值分别为335、467.5、605和640。 ， 分别。仿真结果还表明，热熔体与模具壁之间的传热系数对流动长度有很大影响，特别是在高速注塑成型中。通常，较慢的注射速度需要较高的热传递系数，而较高的注射速度仅需要较低的热传递系数。
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