Laser cutting of CFRP sheet by pulsed Nd:YAG source: Influence of pulse energy, pulse duration and overlapping on kerf geometry and HAZ

Carbon Fibre Reinforced Plastic (CFRP) materials are used for structural applications in different fields. Even though near-net manufacturing of composite materials is possible, cutting and drilling remain unavoidable operations with conventional cutting methods. Laser cutting represents a promising alternative: it does not involve any mechanical cutting force and tool wear. Moreover, thanks to the small spot, laser beam allows to realize very small and complex shape too. However, laser cutting is based on thermal interaction between laser beam and the composite material. It results in the presence of fibres pull out and thermal degradation of both fibres and matrix. The aim of this work is to investigate the influence of the process parameters: pulse energy, pulse duration and overlapping percentage, on the kerf geometry and HAZ extension, in cutting operation of 1 mm CFRP plates using a lamp pumped Nd:YAG working in the regime of short pulses. Experimental results showed that a pulsed Nd:YAG laser, with a nominal power of 150 W, can be successfully used to cut 1 mm CFRP plates up to 11 mm/s. However, an accurate selection of the process parameters is necessary in order to obtain high quality cutting and narrow HAZ.