Research of influence of steel 4X5ŠŠ¤Š ion nitriding process parameters on characteristics of nitrided layer

At the present time an emerging trend for industrially developed countries is towards a wide use of ion nitriding as a method of low-temperature thermochemical hardening processing of machine components, cutting and stamping tools.To a large extent the reason for it is high-tech automated equipment -ion nitriding chamber that solved such disadvantages of gas nitriding as long processing time, fragility of nitration case, low back-toback endurance, process complexity and instability of the results.Due to its advantages nitriding is widely used in all industrially developed countries.However, the possibilities of this thermochemical treatment implying a variety of structural and phase features of nitrided cases are not used on a full scale.Research teams and scientists from all over the world do researches on nitriding technologies to develop new nitrided materials with new properties.Specific usage conditions need controlled nitriding technologies that allow building diffuse layers of different phase composition and structure, which determines the working capacity concerning wear, corrosion, reversed loads, creep-resistance under an elevated temperature.Therefore, it is very important to develop different technologies that allow getting the specifically required structure and phase composition of the nitrided layer that guarantee best performance of products.The aim of the present work is to study steel 4X5МФС ion nitriding process depending on the process variable -chemical activity of glow-discharge.Considering that this steel is preferably used in production of tools for processing of materials in hot condition, according to that the nitrided case should be fully diffusive, without the white layer of iron nitride on the surface.Special attention is paid in this article to the study of nitriding mode issues, in particular, to the processing temperature, nitrogen content in the gas mixture and processing time.As for today, the tendency to nitriding at low (400-550 ºС) temperatures is observed.Rational nitriding time is determined based on the required hardness and thickness of the nitrided layer.However, the difficulty in applying the ion-plasma nitriding method is due to the insufficient study of the workpiece surface saturation process, as well as to the lack of methods for selection of technological processing regimes.It should also be noted that due to the wide possibilities of regulating the ion-plasma nitriding regimes, further study of the ion-plasma nitriding technology is reasonable.