Laser processing of hardmetals: Physical basics and applications

Laser material removal is an effective processing technique for hardmetals, which cannot be machined by chip-removal techniques. The basic physics of the laser-matter interactions and the influence of different laser parameters are discussed, with emphasis on sintered WC-Co specific features. The collateral affected zones and their occurrence mechanisms for laser machining with both nanosecond and femtosecond pulses are discussed. Experiments were carried out with pulsed laser systems operating in IR and UV, with ns and fs pulses and their results endorse the theoretical considerations. The use of direct or indirect laser processing (ns and fs pulses) in the surface engineering of coated/uncoated WC-Co parts is also presented. Subsequently, applications like laser microstructuring of tribological WC-Co surfaces and laser machining of integral chipbreakers are discussed.