OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 27 No. 1 2025 Inrtoduction Low-carbon steels, such as grades 05, 08, and 10 (according to GOST 1050), are a preferred construction material for a wide temperature range from −40 °C to +450 °C due to their excellent ductility. This group of steels is characterized by excellent weldability, resistance to flake formation, and absence of temper embrittlement during operation. Their high ductility makes these steels indispensable in the manufacture of machine parts and assemblies requiring significant plastic deformation, such as cold forming, drawing, bending, and other types of pressure shaping. These steels are typically used for parts and assemblies subjected to moderate static loads under operating conditions [1–3]. In conventional metalworking, mild steels, owing to their low carbon content, are not traditionally subjected to intensive heat treatment to increase their strength. This is because standard heat-treatment methods, such as quenching and tempering, have little effect on the strength properties of these steels. The reason for this is the limited ability to change the microstructure of steels with low carbon and alloying element content. The increase in strength is often accompanied by a significant decrease in ductility, making this approach impractical for most applications. Low carbon steels are valued primarily for their high ductility and weldability, which are essential for various pressure processing techniques [4, 5]. However, Steel 10, with a slightly higher carbon content (0.07–0.14 wt. %), represents an exception to this rule. A small, but sufficient, increase in carbon content opens up the possibility of more efficient heat-treatment methods. Normalizing, quenching followed by high-temperature tempering, and annealing have a marked effect on the microstructure of Steel 10, leading to a finer and more uniform distribution of carbides and, consequently, to improved mechanical properties [6]. These methods make it possible to adjust the balance between strength and ductility, allowing the selection of the optimal processing mode for specific operating conditions. The application of these methods allows to obtain steel with improved strength properties without significantly sacrificing its ductility [7–9]. To further improve the performance properties of Steel 10, particularly to achieve higher strength and fatigue resistance, a promising direction is the use of deformation thermocycling treatment (DTCT) in combination with subsequent heat treatment. DTCT, which involves the cyclic application of high temperature and plastic deformation, allows one to achieve a finer and more refined microstructure, reduce internal stresses, and improve the uniformity of properties across the cross-section of the product [11–14]. Combining DTCT with subsequent normalizing or quenching with high-temperature tempering allows one to obtain steel with significantly improved mechanical properties optimized for specific working conditions, which expands the application area of low-carbon steels. Studies [1–10] indicate the beneficial effect of DTCT not only on mechanical properties but also on a wide range of material properties. This method has a beneficial effect on the physical, technological, and operational properties of a variety of materials, ranging from cast irons [15] to steels with different chemical compositions [1, 2, 16–18]. The effectiveness of DTCT has also been confirmed by studies on aluminum alloys, in particular, hypereutectic silumins [4–6]. This integrated approach allows one to optimize the internal structure of the material, creating more favorable conditions for stress distribution and improving ductility and strength. The mechanisms of property improvement achieved through DTCT involve a complex process of internal stress redistribution and microstructural changes within the metal. As a result, applying this method can significantly improve the strength, ductility, corrosion resistance, and durability of products. The use of DTCT in combination with subsequent heat treatment opens new perspectives for optimizing the properties of steels, especially when it is necessary to achieve a balance of strength and ductility properties [19– 20]. Further research should aim to identify the optimal DTCT modes to achieve the maximum effect, quantifying the effect of different treatment parameters on the structure and mechanical properties of Steel 10. It is also necessary to consider the effect of DTCT on other performance characteristics, such as wear resistance and fatigue strength.
RkJQdWJsaXNoZXIy MTk0ODM1