Effect of Vanadium on the Microstructure and Property of Rebar Steel

Abstract

Rebar steel is used in the construction of various buildings. Vanadium (V), one of microalloying elements, is often added in the rebar steel to improve mechanical property. In order to analyse the effect of V on the microstructure and property of rebar steel, 0.043 wt.% V was added in a 20MnSi rebar steel. The base steel and V added steel were refined in a 50 kg vacuum induction furnace and rolled to plates of 14 mm thick. The mechanical properties of two steels were compared by tensile tests on a Wan-10000 tensile testing machine. The microstructure and precipitation of two steels were analysed by SEM and TEM observations. The microstructures of two steels consist of ferrite and pearlite. However, the grains of V bearing steel are finer. Moreover, fine nanoscale precipitates of V can be observed in V bearing steel. Therefore, the mechanical property of V addition rebar steel is improved by gain refinement strengthening and precipitation strengthening.