Ultrasonic welding of carbon/epoxy and carbon/PEEK composites through a PEI thermoplastic coupling layer

This paper investigates welding of carbon/epoxy and carbon/PEEK composites using the following procedure. Firstly, the carbon/epoxy composite was made “weldable” through a very thin PEI thermoplastic film co-cured on its surface. During the curing cycle, the PEI resin and the components of the epoxy resin system partially diffused into each other generating a gradient interphase between the original epoxy and PEI resins. Subsequently, the...