High strength anti-seismic reinforcing steel bar and production method thereof

The present invention relates to a high strength anti-seismic reinforcing steel bar and a preparation method thereof. The high strength anti-seismic reinforcing steel bar comprises the following chemical components, by mass, 0.20-0.25 wt% of C, 0.40-0.65 wt% of Si, 1.30-1.50 wt% of Mn, 0.020-0.030 wt% of V, 0.010-0.020 wt% of N, 0.25-0.40 wt% of Cr, 0.010-0.020 wt% of Nb, less than or equal to 0.045 wt% of S, less than or equal to 0.045 wt% of P, and the balance of Fe and inevitable impurities. The preparation method comprises: conveying a steel billet into a soaking segment, wherein a furnace temperature is 1150-1200 DEG C; heating for 70-100 min so as to achieve a steel rolling starting temperature of 1020-1100 DEG C; carrying out rough rolling, medium rolling and finishing rolling, wherein a finishing rolling temperature is 950-1000; and carrying out rapid water cooling after finishing rolling so as to reduce a surface temperature to 400-500 DEG C, and then naturally cooling, wherein a temperature after a cooling bed treatment is 680-730 DEG C. The high strength anti-seismic reinforcing steel bar has characteristics of stable mechanical property, good extensibility, good weldability, low strain timeliness, and anti-seismic qualification rate of more than 99.2%.