Experimental study on femtosecond laser micromachining of grooves in stainless steel

Abstract

Laser micromachining of grooves having rectangular profile in stainless steel with high repetition rate femtosecond pulses was investigated. Wide range of process parameters, such as peak fluence (0.15-133 J=cm2), pulse repetition rate (10-223 kHz), cumulative exposure dose, and liquid-assisted method for improving both machining efficiency and resultant structure quality was considered in order to provide understanding of underlying physical capabilities and limitations. Thereby the presence of optimal regimes for obtaining respectively maximum pulse energy utilization and maximum machining performance is proved. Logarithmic law of ablation rate for 400 fs laser pulses centred at 1030 nm with repetition rate of 25 kHz is confirmed for this type of machining. © Lithuanian Physical Society, 2010.