If you want to bake a cake, you have to grease the baking pan beforehand; otherwise the cake will stick to it. Making fiber reinforced plastic components (FRP components) is much the same: release agents are wiped or sprayed onto the surface of the mold so that the component can be taken out once it was cured. However, this approach leaves behind residues of release agents on both the component and the mold. Component surfaces must usually then be manually cleaned a painstaking and potentially critical process, since removing too much material has a negative impact on component quality. Molds, too, must be regularly cleaned but the downtime entails a not insignificant price. Now, the Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM has developed a release film that renders these cleaning tasks. "Our film can be applied to structures of all kinds and makes it easy to release components from molds," says Dr. Matthias Ott, project manager in the Plasma Technology and Surfaces PLATO section. "It features a 0.3 micrometer thick plasma-polymer release layer that leaves no residues on the surface of the component."
This coating on the film is based on development work conducted at the IFAM on producing non-stick component molds using a low-pressure plasma process. First, the mold to be coated is placed in a plasma reactor and atmospheric pressure is reduced to one 10,000th. Next, layering gases are fed into the reactor and a plasma is ignited. Molecules containing silicon or carbon that are injected into the plasma are deposited as a thin layer. Since the molecules are highly reactive, they bond very well with the mold.
Up to 300 percent elasticity
But there's a snag: plasma reactors are at best five cubic meters in volume, which means only relatively small molds can be coated. So the researchers in Bremen, together with experts from Fraunhofer IFAM's Project Group Joining and Assembly FFM in Stade, decided t
|Contact: Matthias Ott |