Welding of Thermoplastic Composites Using Smart Susceptor Technology

This SBIR addresses the NASA subtopic Z3.03, Development of Advanced Joining Technologies. Humanityrsquo;s future in space requires technologies that enable long-duration, long-endurance missions to support human exploration and habitation. Essential to this goal is servicing, assembly, and manufacturing outside of earthrsquo;s gravity. Upon completion of the proposed work, Temper hopes to provide proof of concept of a fast, low-energy and reliable method for welding thermoplastic composites both on Earth and on-orbit. Designs for robotic end effectors to automate the process will also be developed.While able to melt, re-solidify and weld like metals, thermoplastic composites have a higher strength-to-weight ratio and better thermostability. However, reliably joining thermoplastic components has proved difficult and costly. The work proposed in this SBIR will fulfil the objectives of performing prototype welding PEEK thermoplastic composites, validation of welded flat panels and tubular joints, identifying design concepts for robotic end effectors, and development of a method for manual repairs.Temper has developed a Smart Susceptor alloy that controls induction heating to weld thermoplastic composites without the risk of softening, overheating, or deforming the components. This alloy is drawn into wires and fabricated into a weld tape for placement between the materials to be bonded. Utilizing fast and energy-efficient induction heating through alternating magnetic fields, once the Smart Susceptor reaches its Curie temperature, the metal alloy becomes non-magnetic and induction heating stops. Only light pressure (10 psi) is needed to comingle the melted resin and form the weld.Controlled heating can be set for any length of time and cool-down or tempering profiles can be created to control the microstructure of the thermoplastic resin. This technology can be coupled with additive manufacturing so any type of thermoplastic component can be fabricated and assembled on-orbit.