Lutsenko V. The scientific foundation for improvement of steel rod’s thermo-mechanical processing for the wire of small diameter

Object of research - the processes of structure and properties formation in the steel wire rod of wide grade composition processed under different thermo-mechanical modes in the stream of high-speed wire mill. Subject of research -the regularities which determine the impact of thermo-mechanical processing modes on the structure, mechanical properties and qualitative adjectives of the steel wire rod, high-carbon, alloyed welding and low-carbon. Aim of research - the setting of new regularities of structure and properties formation of the metal, the improvements of thermo-mechanical processing technology to increase the ductility of wire rod and provide the production of small diameter steel wire with reduction of financial costs. Research methods: metallographic, electron microscopical, dilatometer, X-ray, quantitative microanalysis of the structural condition, the evaluation of microhardness and mechanical properties. Received results - the setting of new regularities of structure and properties formation in the steel wire rod for small diameter as a result of the thermo-mechanical processing. The obtained steel wire rod has the increased plastic properties, easily removable calx and the structure: high-carbon – the dispersing perlite without closed cementite net, the uniform distribution of the thin decarbonized layer around the periphery; low-carbon – the ferrite with a minimum of perlite; alloyed – the presence of bainite-martensite areas up to 10% in the mixed structure. The results were implemented on РJSC "ArcelorMittal Kryvyi Rih" and OJSC "Byelorussian steel works". Application sector - Metallurgy.