Effect of the pulse duration on graphitisation of diamond during laser ablation

Processes of graphitisation of laser-irradiated polycrystalline diamond surface exposed to multipulse irradiation are studied experimentally. The thickness of the laser-modified layer as a function of the laser-pulse duration ranging from 100 fs to 1.5 μs and the effect of the radiation wavelength on this thickness are studied. It is shown that the diamond graphitisation during multipulse laser ablation is a thermally stimulated process. The dependences of the diamond-ablation rates on the radiation energy density under the action of laser pulses of various durations are presented.