Internal and External Nitriding and Nitrocarburizing of Iron and Iron-Based Alloys

摘要

The research presented in the thesis attempts to contribute to: (1) the extension of fundamental knowledge of the physical chemistry concerning solid-state precipitation phenomena, development and relaxation of residual stresses in surface layers and kinetics of diffusion-layer growth; and to (2) improve insight in phenomena occurring during thermochemical surface treatments as nitriding and nitrocarburizing. In order to pursue the twofold aim, models are used for the materials utilized in practice, i.e. pure iron and binary iron alloys. The thermochemical surface treatments are predominantly performed in nitriding and nitrocarburizing environments based on ammonia-hydrogen gas mixtures.