Ivano-Frankivsk sheet, circle tool steel U8A, HVG, 9XC, 5HNM, R6M5, spring-loaded 65G

In practice, low-temperature, medium and high tempering is used. Low-temperature tempering is carried out at 150–250°C for 1–2 hours. Such tempering sometimes causes an increase in hardness on HPC 1–2 as a result of the decay of residual austenite. Low-temperature tempering is used for tool steels, products after carburizing and surface hardening. Spring and spring steel are subjected to medium tempering at 350-400°C and a troostite structure is obtained with a hardness of HPC 40-45 and sufficient toughness. High tempering is carried out at 450-650°C. In this case, with appropriate exposure, granular sorbitol is formed in the structure, in contrast to the lamellar sorbitol obtained during normalization. Steels with a granular sorbitol structure have a significantly higher impact strength than steels with lamellar sorbitol. Therefore, high tempering after hardening is carried out for parts that experience shock loads during operation. High temper hardening is also called improved Silicon ferroalloys are widely used for alloying special steels, including electrical ones. heat-resistant, scale-resistant, spring-loaded, structural, instrumental, etc. Vanadium in steel is one of the most valuable useful impurities and is widely used both as a deoxidizing and alloying additive in the smelting of structural, spring-spring, tool and other steels. Structural (including free-cutting, spring-spring and heat-resistant steels, steels for valves, heat-resistant, stainless and acid-resistant steels), tool (including for cold and hot working), as well as high-speed steels from Germany, USA, Belgium, England , France, Japan, Norway Steel classification is carried out in accordance with existing state standards and specifications. Steel is classified according to the method of production, purpose, quality and chemical composition. According to the production method, converter steel (various options), open-hearth steel, and electric steel are distinguished. Open-hearth steel and electric steel can be basic and sour. According to the purpose, the following groups are distinguished: structural, instrumental and special (with special physical and chemical properties). Structural steels are used for the manufacture of building structures, parts of machines and mechanisms, ship and carriage hulls, steam boilers and other products. Structural steels can be either carbon or alloy steels. By the name of some structural steels, one can judge their purpose (boiler, shipbuilding, valve, spring-spring, gun, shell, armor, rail, etc.). Silicon is a good deoxidizer, so its alloys are used in the production of steels of many grades. The consumption of ferrosilicon (in terms of FS45) is 0.65 / o from the production of steel. Usually, steels contain 0.12–0.35% Si; in high-alloy silicon steels, its content reaches 2–3% or more. In transformer steel, silicon reduces the hysteresis loss. In combination with other elements, especially chromium, silicon is added to tool, corrosion-II heat-resistant, spring-spring and other steels. The introduction of up to 2% Si into structural steel increases its hardness, strength, elastic and yield limits. In addition, 20 kg of ferrosilicon are consumed per 1 ton of casting in terms of FS18, and the consumption of ferrosilicon in foundry production is 30–40% of the consumption by the steel industry. The standard applies to calibrated rolled products of round, square and hexagonal profiles made of carbon and alloyed steel, high-quality structural spring-spring, increased and high machinability, carbon alloyed and high-speed tool heat-resistant corrosion-resistant, heat-resistant and heat-resistant. The essence of metallographic methods is to determine the decarburized layer by microstructure. Method M is used for structural carbon and alloy steels with a carbon content of at least 0.3%, for tool steels - carbon and alloy steels, as well as spring and bearing steels. Low tempering is used most often for tool steels and for products requiring high surface hardness. Medium tempering, which produces the troostite structure, is generally used for spring and spring steels, as it provides a good combination of increased elasticity and high hardness. Tool steels are subjected to high tempering, which provides a sorbitol structure with high ductility. Silicon as an alloying impurity in steels is contained in an amount of 0.5–0.6% or more. Steel alloyed with silicon has a higher yield strength, greater elasticity, high impact resistance, low residual magnetism, good hardenability, heat resistance, the ability to maintain hardness at relatively high temperatures when quenched, and other useful properties.