Nitriding of car engine parts using ZeroFlow method

This article presents new method of controlled gas nitriding called ZeroFlow, which is used for nitriding of selected car engine parts. Parts such as crankshafts, camshafts, piston rings, poppet valve springs and discs, piston pins or nozzles for unit injectors was nitrided with ZeroFlow method so far. Through the use of simulation models it was possible to develop the specially dedicated process with specific parameters for each of this parts; it allows forming of nitride layer with strictly expected properties: required phase structure with thicknesses of each zone occurs in it and required hardness distribution. Moreover, through the use of simulation models this layers were obtained in in the shortest possible time, which is connected with the lowest energy consumption; therefore, nitriding process using ZeroFlow method is both economical and environmentally friendly. This article will discuss the essence of controlled gas nitriding process, with an emphasis on the influence of process parameters on results of nitriding process. This information are the basis to understand the issue of the kinetics of nitrided layer growth, and as it follows – for its practical application in designing, regulation and control of nitriding processes using simulation models (simulator of the kinetics of nitrided layer growth). Designing of ZeroFlow nitriding processes on the basis of the kinetics of nitrided layer will be shown on the example of nitriding of crankshafts for sports car engines.