Electromagnetic heating for adhesive melting in CFRTP joining: study, analysis, and testing

Induction heating of thermoplastic composites is a suitable and promising technique, due to the very short heating time and the possibility of generating the heat at the interface between the adherends compared with other heating technologies, i.e. owen heating or hot melt gun manual deposition. The aim of this work is to study the electromagnetic induction heating in adhesive bonding of thermoplastic matrix composite materials, when a hot-melt thermoplastic adhesive, Prodas, is used. A numerical model for studying the effect of the process parameters, such as current intensity, maximum temperature and holding time at maximum temperature, has been developed. Experimental tests validated the results of the numerical model; also, the mechanical properties of the adhesive joints were evaluated by short beam shear test and single lap shear tests to define the values of technological parameters allowing for the better joint strength. Moreover, ANOVA analysis was employed to evaluate the most significant parameter which affected the mechanical properties, highlighting the optimum process parameters.