Patent classifications
B29K2879/00
Preparing tool surfaces for composites
Techniques for producing composites outside of an autoclave that have smooth surface finishes are disclosed. The smooth composite surface, free of porosity, can be fabricated by curing the prepreg in a tool that includes a novel microstructure. In conventional composite manufacturing, some degree of porosity appears to originate from trapped gas bubbles that form during curing. The microstructure can provide a mechanism for the gas bubbles to escape from the tooling, thereby eliminating porosity and yielding a smooth surface finish on the out-of-autoclave composite. The microstructure can be applied to the tool surface using an inkjet process applying an acrylic resin curable with ultraviolet light.
COMPOSITE TOOL MOISTURE/WRINKLE BARRIER
A method for fabricating a carbon fiber composite part, for example, a sun shield structural assembly on a satellite. The composite part is fabricated on a carbon fiber/bismaleimide (BMI) composite tool, where a moisture barrier is positioned on the tool prior to carbon fiber part ply layers being positioned on the tool to prevent moisture from the tool from entering the part. In one embodiment, the moisture barrier includes cross-wise strips of aluminum foil. A wrinkle barrier is positioned on the moisture barrier before the carbon fiber part ply layers so that anomalies or wrinkles in the moisture barrier are not transferred to the part layers.