【作者】 周珏；

【导师】 钱欣；

【作者基本信息】 浙江工业大学 ， 材料学， 2005， 硕士

【摘要】 夹芯注射成型作为一种新型的注射成型技术,如何避免芯层熔体前缘冲破现象的出现、获得具有较大芯层熔体穿透深度以及均匀层厚分布的产品对于它的实际应用和理论研究具有极为重要的意义。然而,以往的研究无法为这一特殊的成型技术提供全面、快速的工程分析结果以及动态可视化效果,缺乏系统地为材料的选择与匹配、工艺参数的优化提供参考依据。本研究采用Moldflow公司开发的Moldflow Plastics Insight(MPI)软件,并利用该软件中的Co-injection模块对夹芯注射成型过程进行可视化动态模拟分析,研究讨论物料性能和加工参数如熔体流速等对芯层熔体流动行为包括芯层熔体前缘冲破现象和芯层熔体相对穿透深度、芯层物料分布及夹芯注塑制品均匀性的影响。 模拟研究显示,芯/壳层熔体粘度比R对芯层熔体的流动行为具有显著影响。若R增大则SO_c值(充模过程中恰好不发生芯层熔体前缘冲破时,预填充壳层物料占总物料的体积百分数)变小,芯层熔体发生前缘冲破的趋势减弱,芯层熔体相对穿透深度则相应减小,芯层物料分布均匀性显著降低。这主要与芯层和壳层熔体的相对流动能力有关,以此我们也有理由相信合理地选择物料并予以匹配将极大地影响熔体的流动行为与夹芯注塑制品最终的性能。在众多工艺参数中,更多还原

【Abstract】 As a new injection molding technology, avoiding the breakthrough phenomenon of core melt, obtaining longer penetration length on skin melt and good uniformity of core melt in sandwich injection molding are quite significant for its application as well as theoretic study of sandwich injection molding.However, those investigations dealing with co-injection molding have been published in the past three decades could not provide comprehensive, prompt or visual and dynamic analytical results. Furthermore, they are also devoid of furnishing how to choose the materials for skin and core melt and make combinations, optimize the process settings.On the chance of understanding the melt flow behavior and the mechanism of sandwich injection molding, we made dynamic simulation researches on sandwich injection molding process by employing the co-injection module in the software of Moldflow Plastics Insight. For an integrated CAE software, Moldflow Plastics Insight was the one and only which could provide visual and dynamic simulation results for the co-injection molding process.In this study, the flow behavior of core melt including the breakthrough phenomenon and its penetration length on skin melt, the distribution of the core melt and the uniformity of the goods in sandwich更多还原