Kharkiv sheet, tool steel U8A, HVG, 9XC, 5HNM, R6M5, spring-spring 65G

A steel circle is a rolled metal product with a circular cross section, this uncomplicated product is the basis for the production of various parts on special machines, pipes of various diameters and special engineering structures are also produced from a steel circle, requiring high-precision turning of parts.

Steel circle: characteristics, application, manufacturing.

Among the wide range of rolled metal products used for the manufacture of pipe products, steel circle is in great demand, from which springs, springs, rivets are produced. GOST 2590, a hot-rolled bar is made with a diameter of 8 mm from steel grades 20, 35, 45 and 40 X, Kh12MF, 65G, U8A, 40KhN2M3, R6M5, and others. CVG steel, the cost of which increases due to a valuable additive - tungsten with a mass fraction of 1.2% - 1.6%, nevertheless, is a common alloyed tool alloy and creates competition at the price of an alternative Kh12MF. GOST 5950-2000 lists its chemical composition and mechanical properties. The main substitute is 9XC. The main components are Cr, W and Mn increase the rigidity, wear resistance and heat resistance of this material. The combination of these elements of the periodic table has another advantage - it is well calcined during heat treatment. Also, thanks to manganese, this metal undergoes minor changes in geometry after hardening in the manufacture of high-precision measuring tools. A special kind of steel alloy is spring steel. Spring steel has a number of features - a very high yield strength, hardness, an acceptable level of corrosion resistance. Such material can bend, change its shape under the influence of external factors. During compression, it retains all its physical properties (strength, mechanical stability, chemical inertness). If such a spring is released, the material will return to its normal shape with all physical properties preserved. Spring steel is an alloy that has a very high yield strength. Yield strength is a physical property of a material that characterizes the stress at which the strain continues to increase without increasing the load. In fact, this indicator reflects the ability of the material to maintain its shape when bending and twisting.
The better the material retains its shape during deformation, the higher its yield strength. A high yield strength occurs in the material due to special processing methods (quenching, tempering). This distinguishes spring steel from many other steel alloys, which usually "acquire unusual properties" due to the inclusion of various alloying additives in their composition. For the production of spring steel, low-alloy alloys are used with a minimum amount of additional components. In American, European, Asian countries, medium and high carbon compounds containing chromium are also often used. As the name implies, spring steel is commonly used in the production of springs, torsion bars, leaf springs, piano strings, clamps and many other products. We list the main physical properties of this type of steel:
    High resistance to elastic deformation. This indicator reflects the fact how easily a plastic element is subjected to compression in the presence of external pressure sources. In the case of high resistance, the steel spring is difficult to compress, which helps the part to regain its natural shape after decompression.
Compounds containing a large amount of manganese, nickel, silicon, tungsten, and nitrogen are also used. These components make the material even more plastic, and also increase its chemical inertness (that is, such a material will not react with alkalis, acids, salts). Low coefficient of residual stretching. In the presence of an external pressure source, such a material takes the appropriate form. However, after the disappearance of such a source of pressure, the part again takes on the old shape. The lower the coefficient of residual tension, the weaker the material is subjected to permanent deformation when the external pressure source disappears. Good strength. When a steel spring is compressed, the part does not crack, its crystalline structure is preserved, and does not crumble into several parts. The natural strength of the part can be increased by adding various alloying additives (nickel, chromium, titanium, lead) to the steel alloy. Good corrosion resistance (in the presence of alloying components). If the spring is made of steel with a high chromium content, then it will withstand corrosion well. The physics of the process looks like this: in the presence of chromium in the metal, a thin oxide film is created on the surface of the material. Such a film prevents the contact of iron with oxygen, nitrogen, which minimizes the risk of rust. Chemical inertness (in the presence of alloying components). Alloy additives based on vanadium, tungsten, aluminum, selenium, silicon reduce the likelihood of contact of iron with external substances. Therefore, when a metal comes into contact with any chemical substance, redox reactions do not occur. This makes the spring chemically inert.