Laser Nitriding and Laser Carburizing of Surfaces

摘要

Laser irradiation of surfaces with short pulses in reactive atmospheres (nitrogen, methane) can lead to very effective nitrification and carburization via complicated laser-surface-gas-plasma-interactions. This laser nitriding and laser carburizing and their basic underlying phenomena will be presented and partly explained by results of example materials (iron, titanium, aluminum, silicon), where nitride and carbide coatings can be formed very fast and easily by Excimer Laser, Nd:YAG laser, Free Electron Laser and also by femtosecond Ti:sapphire laser. This implies laser pulse durations from the nanosecond to the femtosecond regime and wavelengths from ultraviolet to infrared. The resulting surfaces, thin films, coatings and their properties are investigated by combining Moessbauer Spectroscopy, X-ray diffraction, X-ray absorption spectroscopy, Nanoindentation, Resonant Nuclear Reaction Analysis, and Rutherford Backscattering Spectroscopy.