Entwicklung einer modellbasierten Fertigungstechnik zur intrinsischen Herstellung von hybriden Verbundwerkstoffen

Research output: ThesisDoctoral Thesis

Abstract

The One-Shot-Hybrid-RTM (OSH-RTM) process describes a manufacturing routine for the intrinsic production of hybrid composite materials. Although this process has already been investigated by research work, it has not yet been adopted by the industry. One of the reasons might be a lack of understanding of the influences of the processing parameters on the quality of the hybrid component. For this reason, this work investigates this topic more deeply. Therefore, model-based approaches to deal with the found challenges are presented. A design of experiments study was carried out to find out which processing parameters have the most influence. It was found that the tool and resin temperature as well as the injection mass flow and their interactions are most critical for the material quality. These parameters especially influence the void content of the composite component of the hybrid. In order to counteract this effect, a flow velocity control system using Darcy’s law was developed. Capillary rise experiments were carried out with the preform to determine the ideal flow front velocity resulting in a minimum void content. Furthermore, the use of vibrating vents at the degassing pipes was investigated. During the flushing process the cyclic closing and opening of the pipes results in a pulsing fluid pressure inside the mould. This forces the voids to vibrate, which in turn helps them to move through the fibrous media more easily. The method can be used to reduce the void content in zones far from the injection point. In addition, the influence of the metal surface structure on the interface strength of the hybrid component was investigated. In order to guarantee constant curing quality of the composite material, a method for online measurement of the glass transition point was developed. This enables a holistic model- and sensor-based process control of all processing steps of the OSH-RTM process occurring in the closed mould

Details

Translated title of the contributionDevelopment of a model-based manufacturing technique for intrinsic processing of hybrid composites
Original languageGerman
QualificationDr.mont.
Awarding Institution
Supervisors/Advisors
  • Mitschang, Peter, Assessor B (external), External person
  • Schledjewski, Ralf, Assessor A (internal)
Publication statusPublished - 2019