ABSTRACT
Polymer composites are in great demand in automotive, aerospace and household products due to their lightweight and high strength-to-weight ratio. Development of complex composite products needs joining of an individual component, but the joining of an individual component made of polymer composites is very challenging because the behaviour of polymers (thermosets and thermoplastics) is different. Thermoplastics can be re-melted after solidification but thermosets cannot be re-melted after solidification. Therefore, joining of thermoset composites and thermoplastic composites is done by different methods. Thermoset composites can be joined with adhesive joining and mechanical fastening, and thermoplastic composites can be joined with fusion bonding and mechanical fastening. Adhesive bonding is not preferred for thermoplastic composites due to the low surface energy of thermoplastics; it is only applicable for thermoset composites. Mechanical fastening is applicable for both types of polymer composites but hole drilling is challenging in the case of composites. There are various methods of fusion bonding such as microwave welding, induction welding, hot gas welding, laser welding, ultrasonic welding and vibration welding, which are used for joining of thermoplastic composites. Among these methods, microwave and induction welding have got more potential to join thermoplastic composites.
