THE INFLUENCE OF CHEMICAL COMPOSITION, HEATING TEMPERATURE AND COOLING RATE ON THE FORMATION OF STRUCTURAL COMPONENTS OF STEELS

Problem statement. The formation of structural components starts with the hardening steels. Therefore, it is important to investigate influence chemical composition, temperature additional heating and cooling rate melt on purpose research – compare in Methods. To determine features state steels, we use microstructural analysis, X-ray microanalysis, diffraction method surface etching specimens nital hot solution sodium picrate. Results. In work, a study steel different carbon, manganese silicon content was carried out. We compared cross-section continuous cast billet similar composition after above liquidus line at 50 °C, 150 °C rates 10–104 °C/s. Scientific novelty. It found that process manufacturing billets, when crystallizer ~104 ºС/s zone steels carbon ≥ 0.5 wt.%, 0.75 wt.% 0.45 δ-ferrite γ-iron dendrites from are completely suppressed. For first time, effect up °С 10–103 °С/s structure experimental investigated. established 102–103°C/s almost inhibits ferrite along grain boundaries, enhances more uniform structure, an increase dispersion components, simultaneous solid-solution steel, improvement mechanical properties addition, decrease volume fraction areas containing liquation elements (manganese silicon) observed. were distributed evenly, which suggests there could be difference elements, condition without melt. Practical value. obtained results allow develop technologies for obtaining structure.