Investigation of physical, mechanical and tribological properties of corrosion-resistant steel with laser surface surfacing of WC100Co4Cr

The article investigated the effect of laser surfacing of WC100Co4Cr powder on the surface of corrosion-resistant steel on hardness, tensile strength and yield strength, coefficient of friction and the amount of wear of products made of alloy structural cryogenic steel. The SVAROG-1-5DR laser complex (Russia) was used for laser processing. Various modes of surface laser surfacing were set. For this purpose, the power of the laser radiation, the speed of movement of the laser beam relative to the treated surface and the focal length were varied. The measurement of physical, mechanical and tribological characteristics was carried out using the equipment of the company “CSM Instruments” (Switzerland). The structure of the alloy was studied by metallography and X-ray diffractometry. The results showed a significant increase in hardness, tensile strength and yield strength and a decrease in the coefficient of friction.

THE ASPECTS OF ALMG6 ALUMINIUM ALLOY DEFORMATION UNDER EXPLOSIVE WELDING

The paper presents the results of a study of the features of the deformation of the main plate made of AlMg6 in the process of explosion welding (with corrosion-resistant steel 08Cr18Ni10Ti). It was found that the end and edge sections of the main plate undergo severe deformation, as evidenced by the constructed maps of the distribution of residual deformations over the plate area. With an increase in the detonation velocity, an intensification of the deformation process occurs, which leads to the appearance of cracks and local spalling of plate fragments. In addition, the results of measurements of the elongation of the main plate showed that a noticeable longitudinal deformation of the plate begins approximately at a distance equal to 2/3 of the total length of the plate. The measured value of the beginning of elongation (240 ± 10 mm) with an accuracy of 95% converges with the calculated value (229 mm).

Коррозионностойкие стали в аддитивном производстве

This review discusses the main methods for producing spherical powder particles of corrosion-resistant steels as a material widely used in all industries. Also the examples of products made by modern additive methods are described. Currently, spherical powder particles of corrosion-resistant steels are used in the following additive methods: selective laser melting, selective laser sintering, direct laser sintering, and electron beam melting. Each of these methods has its own requirements for the characteristics of spherical powder particles of corrosion-resistant steels. The review provides a brief description of the principles of operation of each method and the requirements for spherical powder particles of corrosion-resistant steels. It also considers a detailed description of each method of additive manufacturing with a description of the principle of operation and specific examples of obtaining spherical particles of corrosion-resistant steel powders with indication of their properties (morphology, structural features, chemical composition, fluidity, bulk density). A comparative analysis was carried out with a description of disadvantages and advantages of each method. Examples of the use of spherical particles of corrosion-resistant steel powders for the manufacture of products by various additive methods (including post-processing) are given with description of the final products characteristics. Based on the data presented, a conclusion was made about the preferred methods for obtaining spherical particles of corrosion-resistant steel powders for specific additive methods used in modern industry. The review considers the following methods for producing spherical powder particles: water atomization (atomization of liquid metal with a jet of water under pressure); gas atomization (atomization of the melt with a jet of inert gas (argon or nitrogen) under pressure); centrifugal atomization (atomization of molten metal with a high-speed rotating disc); ultrasonic atomization (atomization of liquid metal by ultrasound); non-contact atomization (atomization of liquid metal with a powerful pulse of electric current); plasma wire spraying; plasma spraying of a rotating electrode; plasma spheroidization.

Investigation of Uneven Properties of Stainless Steel 12Kh18N10T Depending on the Thickness of the Sheet

The authors conduct the research of the properties of a cold-rolled sheet made of corrosion-resistant steel 12Kh18N10T of a variable thickness. Further, they build hardening curves and defined their coefficients. The research identifies the patterns of the thickness impact on the nature of hardening of the sheet material 12Kh18N10T. The authors conduct the measurements of micro-hardness along the sheet thickness. The article confirms the suggestion that hardness in the sheet center decreases for various thicknesses. The authors further present a comparative analysis of hardness values distribution for the corrosion-resistant steel 12Kh18N10T and steel containing 0.08% of carbon. It is revealed that lower material thickness alters the strength parameters of the process and increases the mean material hardness. The authors provide the hardening curves for various sheet thicknesses and the dependence of hardness distribution on the thickness of these sheets.