Executive summary Cornet DeMaCo

Based on literature research, industrial partners, laboratory research and case studies, a decision tool for liquid composite molding processes and a cost estimator tool were developed. The scope was limited to three processes: vacuum assisted resin infusion (VARI), resin transfer molding (RTM) and RTM-light.

In a first step, performance specifications dedicated to the design of composite components were derived. These performance specifications remained central throughout the project, and its attributes were linked to the distinct steps of the decision tool. Dependencies between process selection, selection of materials, tooling design and part design were sought. They led to key specifications which were integrated in the decision tool.

In a second step, three demonstrators were defined in collaboration with the industrial users committee. The chosen demonstrators were: a dinghy in VARI, a tram nose in RTM-light and an automotive control arm in RTM. The aim of these demonstrators was

  1. to undergo the complete design process from idea to small scale production,
  2. to extend the consortiums knowledge on design and processing of complex parts by a design of experiment (DOE) exercise
  3. to demonstrate the selected liquid composite molding processes to the users committee during hands-on workshops
  4. to document and facilitate the dissemination of the results.

Following conceptual and process design, the demonstrator and their molds were designed. Where necessary, mold production was outsourced. Where possible, manufacture was done in-house in order to incorporate hands-on knowledge in the guidelines.

Third, a series of lab experiments was performed. For example, a methodology was validated to simplify the relationship between resin viscosity and the permeability of the textile. Similarly, a draping test was defined which quantifies the drapability of a textile for further use in the decision tool. These experiments were supported by literature surveys.

Forth, a DOE exercise was prepared based on the lab experiments. The aim of this exercise was the validation of the lab experiments in a semi-industrial production process. Subsequently, a series of 10 prototypes was manufactured for the three demonstrators.

In parallel, a cost model was developed. This cost model incorporated cost for material and preforming, tooling and consumables, post-processing as well as depreciation of equipment. The cost model was programmed in Excel and provided with a graphical users interface.

Finally, the results were collected, processed and integrated in the decision tool. Following fine-tuning and layouting, these guidelines will be published as a handbook in autumn 2013 and distributed via a print-on-demand service.