Release Agent Free Manufacture of FRP Components in the Hot Press
The plasma-coated FlexPlas release film developed by Fraunhofer IFAM (in Bremen and Stade) has already been used successfully for a number of years for manufacturing contaminant-free fibre-reinforced plastic (FRP) components. The film is used to replace conventional release agents, and one benefit is that it allows components to be removed from moulds without any residuals. In addition, the mechanical separation of the component from the mould via the film extends the service life of the moulds considerably.
Scientists at Fraunhofer IFAM's research centre CFRP North have successfully expanded the potential applications of the release film: the production of carbon fibre-reinforced plastic (CFRP) using prepregs in a hot press enables the manufacture of large batch numbers with two smooth sides in short cycle times. The release film ensures consistently high component quality and no time-consuming sanding requirement for components post curing. There is also no need to clean or apply release agent to the moulds, which therefore adds value along the process chain. Research results have shown that FlexPlas release film can also be used for moulds of more complex geometry by adapting the process steps and parameters for prepregs in hot presses. The film not only protects the cured component but can also be easily removed, leaving a clean matt surface that can be coated without any pre-treatment.
Joachim Scheller, Project Leader for Adaptive Application Systems, explains the next development steps: "We will start by implementing an already planned automation concept for release agent free FRP manufacture in complex press moulds. As a result, we will increase the degree of automation of the film feed, the inserting of the preform, and the component removal and so further increase the benefit of using FlexPlas release film for the hot pressing of prepregs."