The chemical composition of steel 20GL is optimized. The effect of additional alloying on the properties of low-carbon steels is studied, modifiers are chosen, and their effect on the properties of the steel after heat treatment (normalizing and hardening with high-temperature tempering) is determined. Industrial tests on melting steel 20GL in electric arc and open-hearth furnaces have been successful. The main requirements on structural steels for railway transport castings are high strength properties at an appropriate level of ductility and toughness for avoiding brittle fracture of parts operating under dynamic loads and at low temperatures. Steel 20GL is used for fabricating cast parts of rolling stock. Its chemical composition and mechanical properties are regulated by the GOST 22703-91 standard that stipulates four categories of properties (Table 1). Category I corresponds to minimum permissible properties and category IV corresponds to the highest ones. Until recently cast parts for railway transport have been produced from steel 20GL with properties of category I. However, the transition to production with category II is the task of the day and the transition to European quality of the metal, which corresponds to categories III and IV, is the task of the nearest future.
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