Processing of ultra-hard materials with picosecond pulses: From research work to industrial applications

Abstract

The ultrashort laser processing of the cutting tools and cutting inserts from tungsten carbide, ceramic and metal composites (CERMET), and polycrystalline diamond materials was demonstrated, and the ablation rates of mentioned ultra-hard materials were evaluated for a laser wavelength of 1064 and 532 nm. The optimal processing throughput was estimated. Laser manufacturing was performed with the five-axis computer numerical control (CNC) machine and scanner for beam translation with the high speed and the ultrashort ∼12 ps pulse duration high repetition rate laser source. The systematic approach was implemented in an experimental variation of process parameters that play a significant role in processing quality. By varying the laser fluence, pulse overlap, and layers’ count, different material removing rates can be achieved from 300 nm/layer to ∼18 μm/layer. The submicrometer removing rate involves a high precision control of the structure depth. It was demonstrated that only by a minor change of the processing parameters, the surface roughness of the material could be minimized down to Ra < 300 nm. Rough and smooth processing can be combined to optimize the structure processing throughput.