Estudo do perfil de carbono na camada nitretada do aco AISI M2

The aim of this work is to investigate the redistribution of carbon normally observed after plasma nitriding of steels. Samples of AISI M2 steel were plasma nitrided in a 60 kW reactor varying temperature, time, and treatment gas composition. X-ray diffraction, glow discharge optical spectroscopy – GDOS, optical and scanning electron microscopy analysis were performed. According to GDOS analysis, the samples presented decarburization on the surface of the nitrided layer and a carbon enrichment zone in the interface layer-substrate. For some conditions of treatment, it was observed the presence of a small peak of carbon in the interface between the compound layer and the diffusion zone. The results suggest that the compound layer works as a barrier for the decarburization process