Study of hardening and structure of maraging powder steel grade PS-H18K9M5TR (18%Ni+9%Co+5%Mo+1%Ti+1%Re+66%Fe)

Abstract

Relevance. High-strength steels are increasingly in demand in modern industry for various applications. Maraging steels are the primary material in the manufacture of most aircraft parts as well as machine-building components. This type is low-carbon and is rich in nickel, which forms martensite when cooled as well as demonstrates properties such as high hardness, wear resistance, etc. The hardening process is the main factor affecting the functional properties of maraging steel. At certain temperatures, austenite has the ability to transform into various kinds of phases. However, the shortcoming that lies in the presence of some impurities limits the established types of improvement technologies, leading to the search for innovative methods to improve the characteristics of steel without losing any of the desired properties. Good qualities appear in maraging steels mainly after treatment with a solution at a temperature of about 1000℃ and during aging at a temperature of about 490℃. Purpose. Thus, the purpose of this research paper is to analyze the structure of maraging steel powders and study the thermal effect on its properties. Methodology. In this paper, powder steel was pressed by spark plasma sintering technology at a pressure of 60 MPa to a powder compact and heated at a temperature of 1100℃ for 180 s at a rate of 20℃/s, after which the samples underwent phase and elemental analysis, their hardness was measured, the value of which amounted to about 60 HRC. Results. The results of this scientific research demonstrate the presence of a variety of precipitates. The presence of impurities such as Co, Ti, and Re led to an improvement in strength due to martensitic phase transformation and precipitation hardening, as well as slowed down the diffusion process. Conclusions. In addition, tasks for further research on the issue of manufacturing maraging steels by the additive manufacturing method were identified. This technology enables obtaining strong maraging steels based on a powder mixture with the required characteristics