Structure of the surface layer of high-chrome steel nitridated in the elion regime in the plasma of a suspended arc discharge with a heated cathode
Year: 2023
Type: article
Abstract: The purpose of this work is to reveal the patterns of formation of the structure of the surface layer of high - chromium steel subjected to nitriding in a low - pressure gas discharge plasma using a plasma generator with a hot cathode " PINK ". Heating of the samples to the nitriding temperature was carried out by the ionic component of the plasma , as well as by the electron and ionic components of the plasma ( elion mode ). The object of the study was heat - resistant corrosion - resistant steel of the austenitic class grade 20 X 23 H 18 ( foreign analogue of AISI 310 S ). The relevance of research is due to the relatively low level of hardness and wear resistance of steels of this class . Nitriding of steel was carried out on the TRIO installation , retrofitted with a switching unit for implementing the aelion ( electronic and ionic ) processing mode . It has been established that the thickness of the hardened layer is (55-60) pm and weakly depends on the method of nitriding , temperature ( in the range of 793-873 K ), and duration (3-5 hours ) of the process . A nitriding regime has been revealed that makes it possible to form a surface layer with a microhardness of 13.7 GPa ( ionic heating mode ) and 10.8 GPa ( elion heating mode ). It has been established that the high strength and tribological properties of nitrided steel are due to the formation of a nanocrystalline structure in the surface layer , the main phases of which are iron nitrides Fe 4 N and chromium nitrides CrN . It is shown that heating the samples to the nitriding temperature in the aelion mode , which uses the electron and ion components of the plasma , leads to a significantly lower level of material roughness compared to the samples heated during nitriding by the ion component of the plasma .
Source: Siberian Aerospace Journal
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4367156133