Welding thermoplastic composites using microwave energy

One of the most important areas of the application of industrial microwave technology for materials processing is curing polymers and polymer based composites, and this is currently in a state of considerable flux. Curing of thermosetting composites in multimode applicators and joining of a range of thermoplastics in ridged waveguides have been some of the major achievements in the field. This paper extends the applications horizon of microwaves in the area of random fibre reinforced thermoplastic composites joining, and places emphasis on the development of equipment and facilities aiming at maximising bond quality. It discusses the microwave facility used. The effect of power input and cycle time is detailed together with the underlying principles of test piece material interactions with electromagnetic field. The process of heterogenous joining, with filler material, or primer, of 33% by weight of random glass fibre reinforced nylon 66, polystyrene (PS) and low density polyethylene (LDPE) thermoplastic composites is mentioned.