Metal micro drilling combining high power femtosecond laser and trepanning head

Abstract

Trepanning heads are well known to be efficient in high aspect drilling and to provide a precise control of the hole geometry. Secondly, femtosecond lasers enable to minimize the heat effects and the recast layer on sidewalls but are typically used on thin sheet. The combination of both present a high potential for industrial applications such as injector or cooling holes where the bore sidewall topology has a major influence on the dynamics of the gas flow. In this paper we present results using this combination. The effect of pulse energy, repetition rate and revolution speed of the head on both geometry and roughness are discussed. The quality of the sidewall is checked by roughness measurement and by metallographic analysis (SEM; chemical etching, micro hardness)

Comparison of selected processes for surface microstructuring of complex mould for an implanted device

“…al. has reported metal micro drilling by femtosecond laser combined with a trepanning head, and high-aspect micro holes with high-quality sidewalls can be achieved 20 . As an initial test, a flat a piece of stainless steel was machined by a femtosecond Ti: Sa laser (Demtopower Compact Pro, Femtolasers Produktions GMbH, Vienna, Austria).…”

Statistical Approach to Fiber Laser Microcutting of NIMONIC® C263 Superalloy Sheet Used in Effusion Cooling System of Aero Engines

“…This results in a better focussing and then higher cutting speeds with comparable or better kerf quality, in term of: small dimension, spatter and dross absence, recast layer and HAZ extension. Furthermore, this characteristics are enhanced by the use of high quality short and ultrashort pulsed laser [13][14][15][16][17][18]. However, when the material thickness is limited (<1 mm), the use of a high quality fibre laser, working in CW or modulated regime, could be an economical and practical solution, as demonstrated in [19][20].…”