The effect of plastic deformation on the structure and properties of 20CRMNSI steel obtained by additive electric arc cultivation

Abstract

Abstract. The paper presents the results of a study of the influence of the degree of deformation under uniaxial tension on the structure and physico-mechanical properties of 20KHGSA steel obtained by 3D printing by electric arc surfacing. It is shown that additive technologies for the production of materials and products have become widespread. In particular, the technologies of electric arc cultivation (WAAM method) are of particular interest. The undoubted advantage of the WAAM method is the relatively low cost of equipment and surfaced material (in comparison with laser or electron beam equipment), as well as the possibility of obtaining large-sized blanks with the least number of defects. A comparative analysis of the influence of the direction of surfacing on the properties of samples during mechanical tests is carried out. It is established that the destruction of the material occurs more intensively in the sample cut perpendicular to the direction of surfacing. Non-destructive methods for estimating the deformed state of 20KHGSA steel under uniaxial tension are proposed. It is shown that one of the most sensitive non-destructive methods for assessing the deformed state of metallic materials is the ultrasonic echo-pulse control method, which is a useful quantitative tool for monitoring the state of the material due to its simplicity and reliability. The magnetic control method has a high sensitivity to deformations. The dependence of the magnetic properties of metals (in particular, the coercive force Hc) on the degree of deformation of the material is shown