Effect of Niobium on Microstructure and Mechanical Properties of a Hypereutectoid Steel

High-carbon steels have been used to high-strength steel wire and strands for prestressing concrete. The necessity of levels at increasingly larger diameters rods is a technological challenge. Two with without Nb were obtained in mill, submitted detailed microstructural (previous austenitic grain size, pearlite interlamellar spacing colony size) mechanical characterization through tensile tests hardness. Hot torsion dilatometry performed simulate processing verify the influence on phase transformation. Adding resulted refinement size colonies but had no effect pearlitic spacing. There was decrease start transformation temperature austenite/pearlite therefore an increase hardenability Nb-added steel. Finally, addition proved be technical economical way strength reduce variability properties.