On the issue of using nitrocarburizing for surface hardening of parts made of 30KhGS steel

Purpose. Study of the elemental and phase compositions, as well as the microhardness of the surface of the cutter body of the KZTS A6/20 road milling machine made of 30KhGS steel, in order to use nitrocarburizing for its surface hardening. Methods. Modern methods and equipment were used to achieve the set goal. Using the X-ray analyzer built into the Quanta 600 FEG scanning electron microscope, X-ray spectra were determined at specific points on the sample surface. The phase composition of the sample was studied by X-ray diffraction on a Rigaku Ultima IV diffractometer in Cu-Kα radiation using Soller slits using the ICCD PDF-2 DB (2014). The diffraction maxima were described using a superposition of the Gaussian function and the Lorentz function. Using the DM-8 automatic microhardness analysis system using the micro-Vickers method, the microhardness of the samples was studied by transverse section. Results. The following were obtained as a result of the study: an X-ray diffraction pattern of the elemental composition of the cutter body of the KZTS A6/20 road milling machine, showing that the ratio of the elements corresponds to the composition of alloyed structural steel 30KhGS; a diffraction pattern showing the crystalline phases of α-Fe and Fe2O3 with different sizes of crystallites, as well as data on the position and interplanar distances of all reflections. The microhardness of the sample surface was determined: HV0.01 = 437.6. Conclusion. The completed study will allow the development of recommendations for the practical application of chemical-thermal treatment methods, by means of which it is possible to carry out surface hardening of parts made of 30KhGS steel, in particular the body of a road milling cutter.