Abstract
Discovering microstructural features of white layer in a nitrided part has appealed to many scientists and researchers. A slight change in microscopic properties can bring a huge difference in their macro-scale behavior. A thorough knowledge of the compound (the white layer) and of the diffusion zone will enable materials scientists to monitor the grain size (the phases within the material), which alter the macro-scale toughness and strength and finally the amount of porosity. Unlike carburizing, which is a more matured technology, nitriding specifications are genetically stated as surface hardness and hardness at depths. No constituents or type and percent of compounds are mentioned. This paper will attempt to address methodologies used to identify different constituents of both the compound and the diffusion layers of a nitrided part. Three different materials have been heat treated for this study. Three different methods of investigation were used: optical microscopy, electron dispersive spectroscopy (EDS) and electron probe microanalysis (EPMA). This is the beginning of a series of investigations which are underway. In this article, information already known will be the starting point. In future articles, more in depth investigation of the white layer and of the diffusion zone will be shown.
