Effect of fiber content and wall slip phenomenon on the polymer filling behavior in thermoset injection molding and simulation process

近年来，由于仿真过程的各种优点，在工业制造环境中使用仿真过程的需求有所增加。良好的模拟结果的必要条件是材料数据的正确和完整。在热固性注射成型模拟中，其材料数据来源有限，很少能从模拟工具的数据库中获得。材料数据的生成需要流变学和热性能测量方面的广泛知识以及优化算法。此外，为了准确地模拟热固性注塑复合材料的过程，需要对热固性注塑复合材料的充模特性有深刻的了解。在此问题上，塑料工程教授通过自己开发的一种有效而有用的方法，发现了热固性塑料和热塑性塑料完全相反的充模行为。具体来说，对于热固性注塑成型，热固性熔体和壁面之间存在强烈的滑移，这在热塑性材料的注塑成型中是没有的。然而，诸如纤维和填料量、模具表面粗糙度和模具压力等变量对打滑现象的影响尚未得到研究。此外，将迄今为止未知的滑移现象的知识整合到仿真模型中仍然缺乏。因此，本研究计划重点关注两个科学关键目标。一是全面了解纤维增强热固性注塑复合材料的影响参数与充型性能之间的关系。二是建立描述所研究的充型行为的仿真模型。模拟结果与实验结果的验证将显示模型的质量是否足以开发真实的热固性注射成型模拟工艺，这有助于工业公司增加设计的成功，缩短开发周期以及预测潜在的缺陷。

The demand of using simulation processes in the industrial manufacturing environment has been increased in recent years because of its various advantages. The necessary requirements for good simulation results are correct and complete material data. With thermosets injection molding simulation, its material data are found in limited sources and are seldom available from data bank of simulation tools. The generation of material data requires an extensive knowledge in measurement of rheological and thermal properties as well as optimization algorithm. In addition, to simulate exactly the thermosets injection molding compound process, it requires a profound knowledge in the mold filling characteristics of thermoset injection molding compounds.Concerning this matter the Professorship of Plastics Engineering found a completely opposite mold filling behavior of thermosets and thermoplastics by an own-developed effective and useful method. Specifically, for the thermoset injection molding, there is a strong slip between the thermoset melt and wall surface, which is not found for the injection molding of thermoplastic materials. However, the variables like amount of fiber and filler, the mold surface roughness and mold pressures that can influence the slip phenomenon has not yet been investigated. Furthermore, the integration of the knowledge about the up to now unknown slip phenomenon into the simulation models is still missing. Therefore, this research proposal focuses on two scientific key goals.The first one is to gain a complete understanding of the relationships between the influencing parameters and the mold filling behavior of fiber-reinforced thermoset injection molding compounds. The second one is the development of simulation models which describe the investigated mold filling behavior. A validation of the simulation results with experimental results will show whether the quality of the models is sufficient for the development of an authentic thermoset injection molding simulation process, which helps industrial companies to increase the success of the design, to shorten development cycles as well as to predict potential defects.