from the conferences organized by TANGER Ltd.
Due to the increasing requirements for ensuring the function of the component and technical units in operation, monitoring and influencing chemical and physical changes in the properties of materials in the surface layer of the component is of considerable importance. These changes take place both as a result of the machining process, but can also be significantly influenced by the formation of diffusion layers, using suitable surface technology. These technologies include, for example, plasma nitriding, which significantly increases the useful properties of the surface. However, plasma nitriding also has a direct effect on the geometric quality of the surface of the part, ie the process of saturating the surface with interstitial elements initiates structural stress mechanisms, which lead to changes in surface structure and dimensional changes. The presented article deals with the evaluation of the change in dimensions and the change in the surface roughness of samples from medium-alloyed, noble steels 34CrNiMo6 and 14NiCr14. The change in the longitudinal dimension of the samples was evaluated using a 3D coordinate measuring machine and the surface roughness using a coherent correlation interferometer (non-contact). The evaluation of the surface roughness was focused on the change of 2D functional parameters Rk, Rpk, Rvk and the height parameters Ra and Rz were also evaluated. The dimensional changes were higher for 14NiCr14 steel (0.030 mm), compared to 34CrNiMo6 steel (0.023 mm). The nitriding process further led to changes in the evaluated 2D parameters of the surface roughness, which were more pronounced for 14NiCr14 steel.
Keywords: Plasma nitriding, surface roughness, change of size, functional parameter© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.