MANUFACTURING OF DOUBLE-CURVATURE CF/PPS CONTINUOUS-FIBRE WOVEN THERMOPLASTIC COMPOSITE PARTS THROUGH STAMP FORMING

The stamp forming process was used to manufacture double-curvature parts made of 4-ply pre-consolidated woven carbon fibre/Polyphenylene Sulfide (CF/PPS) thermoplastic composite. The process consists in heating a... [ view full abstract ]

The stamp forming process was used to manufacture double-curvature parts made of 4-ply pre-consolidated woven carbon fibre/Polyphenylene Sulfide (CF/PPS) thermoplastic composite. The process consists in heating a pre-consolidated blank in an infrared oven and quickly transferring it to a hot press where a two-part tool forms the blank to a desired shape. Through a series of experiments, different aspects of the stamp forming process such as the laminate stacking sequence and the tool minimum radius of curvature were investigated. Results revealed that under certain sets of processing conditions, high quality parts can be made without any visible wrinkles or defects on the surfaces. This could be achieved even for the most aggressive tool design, i.e., smallest investigated radius of curvature. The void content was estimated by cutting off samples at various locations of the parts and observing the cross-section by optical microscopy. Results revealed a void content as low as ~0.1%. The part cross-section thickness variation was verified using a coordinate measuring machine (CMM). An average thickness increase of ~6.5% was obtained over the part area.