Carbon fiber reinforced polymer (CFRP)-materials show very inhomogeneous optical and thermal properties. Therefore laser processing of such materials often causes large thermally damaged regions reported by several authors with sometimes contradictory results.
Thermal damage of the fibers and the surrounding plastic material is not only caused by the incident laser beam but inevitably also by the large heat flow along the fibers. The analytical treatment of the thermal energy balance allows determining the minimum obtainable damage caused by heat conduction. The model assumptions and the influence of the laser parameter on the resulting minimum obtainable damage are discussed. The results are compared with experimental findings and with a 2-D numerical solution of the heat conduction equations.