TWI Industrial Member Report Summary 1033/2013
By Chris Worrall
Recent renewed interest in thermoplastic composites has not been translated to widespread uptake of these materials. One reason for this is the limited technology for joining. Thermoplastic composites can be welded using a variety of techniques: Induction, Resistive Implant etc, but thermal control of the processes can be difficult. Focusing the heat at the weld interface offers improved control of the welding process and better quality welded parts.
The predicted production rates for single-aisle aircraft exceed the current economic production capabilities of thermoset composites, which rely on long cure cycles. Thermoplastic composites (TPCs) can offer shorter processing times to meet these rising production rates, and can also be joined by welding; an attractive assembly approach for complex structures. In the Automotive industry too there is a growing need for technologies that achieve high production rates to form lightweight parts that will ultimately be joined to themselves, and other materials, to form complex assemblies.
- TWI has developed a novel induction technique that has wide potential for welding thermoplastic composites.
- Being able to focus the heating at the joint interface make this technique ideal for improved quality welding of thermoplastic composites.
- It offers an attractive alternative to current adhesive bonding and mechanical fastening techniques.
- It could also be applied to focused heat curing of adhesive bonded joints, broadening its application to joining thermoset composites.