Effect of contact resistances on the thermal conductivity of an unconsolidated fibre-reinforced thermoplastic prepreg stack

This paper deals with the effect of contact resistances on the effective through-the-thickness thermal conductivity of an unconsolidated thermoplastic composite prepreg stack. The thermal conductivity of a 40-ply unconsolidated APC-2 stack is experimentally determined and the result compared with published values for a consolidated APC-2 laminate. Experimental results show that the effect of increasing the pressure on or temperature of the stack is to reduce the contact resistances between the plies and hence increase the effective thermal conductivity of the stack. In general, the results presented show that contact resistances between the individual plies cause the effective thermal conductivity of the unconsolidated stack to be three times lower than that of a corresponding consolidated laminate.