Presented by: Nitrex Metal, Inc.
Controlled ferritic nitrocarburizing processes such as Nitreg®-C, when followed by post-oxidizing, are known to yield a very high esistance to corrosion. The control equipment and software used for Nitreg®-C processes meet the aerospace specification MS2759/12A, making it possible to consistently achieve the required metallurgical results. Currently, this standard limits process recipes to be controlled via Kn and Kc set points for each stage of the process. That is, they do not take into account the dynamic shift of reactions occurring at different temperatures, and consequently they do not produce a niform nitrided structure. On the other hand, our new concept of phase control takes into account the dynamics of dissociation and diffusion that shift with temperature. In other words, Nitrex is now able control the process parameters via floating set points that follow phase boundaries throughout the process. This approach opens a wide field in nitriding and nitrocarburizing process control specifically aimed at a number of factors such as a defined porosity, but also obtaining monophase white layers, high carbon epsilon phases, and low carbon white layers. In this presentation we will show how such control is applied, and how it leads to optimum corrosion resistance by dense white layers with controlled magnetite oxide layers in the newest Nitreg®-C/ONC® technologies.