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

• Applicant: Professor Dr.-Ing. Michael Gehde (†)
• Subject Area: Plastics Engineering
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 437971453

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.

• DFG Programme: Research Grants