Investigation of increased drilling speed by online high-speed photography

Percussion drilling of through holes in stainless steel (grade 304/EN 1.4301; 8 mm) is carried out with temporal and spatial superposed Nd:YAG laser radiation of μs- and ns-pulsed laser sources. The drilling progress with superposed laser radiation is determined and compared with the drilling progress without superposed laser radiation. The process gases oxygen, helium, and argon are used. Coaxial and lateral high-speed photography is used to correlate the optical emission monitored with the drilling progress.