Heating mechanisms in induction processing of carbon fiber reinforced thermoplastic prepreg

Experimental studies have demonstrated the ability of carbon fiber reinforced thermoplastic prepreg stacks, under vacuum pressure, to heat rapidly (similar to 50 degreesC/s) in the presence of an alternating magnetic field. Results indicate that contact resistance heating at overlapping fiber junctions of adjacent plies is the dominant heating mechanism. The key process parameters are prepreg surface characteristics, pressure and induction parameters. A model has been developed to simulate heating mechanisms in a two-ply prepreg stack under various processing conditions. Heating pattern predictions show good correlation with experimental results, for various ply orientations. Rapid and uniform heating of carbon thermoplastic prepreg stacks, by induction, shows potential as a non-autoclave lamination process with high throughput.