UDK 66.07 © Jerzy Michalski, Jerzy Dobrodziej, Jan Tacikowski, Jacek Wojutynski, Jerzy Ratajski, Piotr Wach SIMULATION FOR PREDICTION OF THREE-COMPONENT ATMOSPHERES IN THE CONTROL SYSTEM OF THE GAS NITRIDING PROCESSES The article presents the application of numerical methods for simulating (prediction) nitriding potential changes, and a discharge of three-component nitriding atmosphere. <...> Development trends of developed simulation methods in the context of their application in designing and controlling industrial gas nitriding systems. <...> Ключевые слова: nitriding, simulation of process, nitriding potential, three-component nitriding atmosphere, models, algorithms. <...> In the case of complex processes, such as thermo-chemical processes, the following important research and technical problems are considered: – The correlation of the dynamic characteristics of the process temperature and nitriding potential for various types of steel and different systems of heat capacities: charge mass-furnace-heating space between the furnace and heating sections; – The selection of appropriate nitriding potential and atmosphere flow rate, because nitriding atmosphere composition is important for the kinetics of layer growth, particularly when the gas nitriding process is an element of duplex or hybrid treatment; – The stabilisation of temperature within the process duration; – Taking into account the synergism of physicochemical phenomena occurring in the process; – Complicated technical conditions of in-situ measurements enabling to control on the basis of results of the process states; – The necessity of fulfilling industrial requirements in the scope of remote control (and regulations when needed) of the course of the nitriding process and the diagnostics of emergency states; – The optimisation of controlling, including technical, and economical aspects; and, – The development of efficient predictive models for controlling, which is essential because of thermal inertia in controlling of the retort temperature and delays in reaching the preset nitriding potential. <...> The importance of gas nitriding in industrial applications is proofed by the fact that, for example, in Canada and USA, which belong to the group of the most industrialised and innovative countries in the world, the gas nitriding technologies constituted 76%, 69%, 58% of the nitrocarburizing, carbonitriding and nitriding technologies, respectively [2]. <...> Such precise control is essential to obtain physico-chemical and maintenance properties of manufacПроблемы машиностроения и автоматизации, № 1 – 2010 109 triding technology results from the following advantages: – The relatively low temperature of the process n comparison with other methods of layer constitution; – The possibility of nitriding <...>