AbstractThe laser cutting of a glass ceramic matrix composite containing about 50 vol.-% aligned SiC fibres has been investigated. A 2 kW CW (continuous wave) CO2laser equipped with an x–y table was used with varying beam diameter, power, and table speed to give a range of processing conditions. The dimensions (depth and width) of the cuts were measured as a function of the processing conditions and the cut surfaces were examined using scanning electron microscopy and X-ray diffraction. Full through-section cuts, having vertical sides? were obtained using a narrow 1mm diameter beam operating at a (power density) / (table velocity) ratio in excess of approximately 30 J mm−3. The surface condition after laser cutting was superior to that obtained using conventional diamond sawing.MST/1168