STRUCTURE AND PROPERTIES OF THE NITROGENATED LAYER OF X40CrMoV5-1-1 STEEL OBTAINED IN THE ION-PLASMA TWO-STAGE VACUUM-ARC DISCHARGE

In the production of pipes from corrosion-resistant steels on tube rolling mills, a relevant problem is the low durability of the pipe tooling. Therefore, the creation of high-performance and durable tools is primarily associated with obtaining and processing materials capable of withstanding harsh working conditions. The paper analyzes the structure and properties of the nitrogenated layer formed on the surface of the stamping tool made of X40CrMoV5-1-1 steel using the ion-plasma nitriding technology in a two-stage vacuum-arc discharge, aimed at improving the wear resistance of the pipe pressing tool. The article proposes, substantiates, and calculates a mathematical model of microhardness distribution with depth of the diffusion layer based on the Kolmogorov-Johnson-Mehl-Avrami equation, which takes into account phase transformations associated with reaction diffusion processes during nitriding. An analysis of the thermodynamic stability of nitride diffusion zones responsible for improving the wear resistance of the tool is provided.