| Abstract: | A thermodynamic evaluation, based on simultaneous measurements of the mechanical work and the concomitant heat of deformation in a stretching micro calorimeter, was performed on polycarbonate/carbon fibre (PC/CF) micro composites. Single fibre composite specimens containing sized and unsized CF were subjected to different thermal treatments. Thermodynamic effects of deformation were measured for both elastic and plastic deformation ranges. In the elastic/beginning of plastic deformation ranges the internal energies and heat effects of deformation of micro composites exceeded those of matrices. The highest internal energy and, in turn, the highest fibre/matrix adhesion, was found in the case of the quenched micro composites with sized fibers. Thermodynamic effects of deformation and calculated material constants of PC were in reasonable agreement with data in the literature. |
