Situation

Heat treating is one of the most important parts during industrial production processes and in the field of surface treatment processes, especially nitriding/nitrocarburizing and carburizing/carbonitriding. Today, simulation of carburizing is state of the art and fast simulation programs are available and used in industry. But for simulation of nitriding and nitrocarburizing processes only few publications and no industrial application exist. This unsatisfying situation shall be changed by this project. Main problem for the simulation tasks are complex but not unresolvable couplings between different physical effects: binary or ternary diffusion, growth of a compound-layer, and formation of precipitations. At IWT a lot of experimental results and experience of nitriding and nitrocarburizing processes exist. But up to now no satisfactory simulation can be done. On the basis of existing results, experiences and of complementary experiments a simulation program is to be developed.

Engineering Aspects

A result of the engineering part of the project should be that nitriding and nitrocarburizing processes can be modelled and simulated in a way, that chemical state (carbon and nitrogen profile, thickness of the compound-layer, density of constituents) of the surface near regions of workpieces during and after technical nitriding processes can be predicted.

Mathematical Aspects

The mathematical part of this project is to develop a simulation routine for the nitriding/nitrocarburizing process. For some problems (e.g. formation of precipitations) suitable modells have to be evolved. Moving-boundary as well as phase-field modells will be used for the simulation routine.