Sagura L. Improvement of the chemical composition and thermomechanical treatment of the rolled wire for manufacture of high-strength reinforcing stands and springs

High carbon wire rod, microalloyed by vanadium and/or boron for manufacture of high-strength reinforcing stands and springs. Improvement of the chemical composition and thermomechanical treatment of the rolled wire for manufacture of high-strength reinforcing stands and springs. Metallographic, electronmicroscopic, differential-thermal analysis, mathematical modelling and multicriteria optimization. The kinetics of austenite transformations during continuous cooling of steel C80D2 has been studied and thermokinetic diagram (CCT) has been plotted. The time interval of speed cooling of austenite steel С80D2 (~ 5...2 0C/s), within which the line CCT the end of the transformation of austenite exceeds the line of his beginning has been installed. The introduction of carbon steel boron leads to increased as a strain hardening and uniform elongation due to increased dispersion of perlite, partial-bound nitrogen and formation of dispersed and plastic boron nitrides has been installed. The increase of temperature pickup wire rod in coils after hot deformation promotes the growth of austenitic grain, caused by development processes static crystallization, and the formation of more specific boundaries has been installed. In conditions of JSC "Moldova steel works" the complex technology of production of the high-carbon rolled wire, microalloyed by vanadium and boron has been developed and implemented. The technical agreement TA 518/71915393-01-2010 "About the technical conditions of supply of quality of the high-carbon rolled wire for the manufacture high-strength armaturnoj a wire" has been developed. Cooperation of JSC "MSW" - JSC "Severstal-metiz", JSC "MSW" - LLC "Busol" and JSC "MSW" - PJSC "Dneprometiz" through energy-saving technology of production of high-strength wire direct (without preliminary or intermediate patenting) drawing for the manufacture of high-strength reinforcement strands and springs has been developed and introduced. Metallurgical production, metalware production.