HRB500E V-N high-strength anti-seismic steel bar and production method thereof

Abstract

The invention provides a HRB500E V-N high-strength anti-seismic steel bar and a production method thereof. The HRB500E V-N high-strength anti-seismic steel bar comprises the following chemical components: 0.21-0.25 wt% of C, 0.45-0.65 wt% of Si, 1.35-1.55 wt% of Mn, 0.055-0.070 wt% of V, 0.0145-0.0165 wt% of N, not larger than 0.045 wt% of S, not larger than 0.045 wt% of P, and the balance of Fe and unavoidable impurities. In the invention, through decreasing V and increasing N, and properly controlling initial rolling temperature, finishing rolling temperature, rolling speed, and rolling pass and time, not only a precipitation strengthening effect of the V is fully developed, but also the strength of the steel bar is remarkably improved. Meanwhile, the HRB500E V-N high-strength anti-seismic steel bar maintains favorable plasticity and tenacity with an anti-seismic qualification rate as high as 99.0 percent; cost per ton is reduced by 40-50 yuan RMB compared with that of a V-N microalloying hot rolling process; and the invention is beneficial to the protection and the reasonable utilization of V-N alloy scarce mineral resources, and plays a better promoting role for the popularization and the application of the HRB500E V-N high-strength anti-seismic steel bar.

Description

technical field [0001] The invention relates to a low-cost high-strength anti-seismic steel bar and a production method thereof, in particular to a HRB500E vanadium-nitrogen high-strength anti-seismic steel bar and a hot rolling process production method thereof, belonging to the technical field of metal material processing and forming. Background technique [0002] With the continuous development of urban construction and social progress, the buildings of various countries in the world have developed towards large-scale development. In order to improve the safety of large buildings, the foreign construction industry has generally adopted hot-rolled ribbed steel bars with good welding performance and high strength. For example, EU countries and North America basically use 500MPa and above steel bars. Compared with 335MPa and 400MPa steel bars, 500MPa steel bars have the advantages of high strength, large safety reserves, good seismic performance, saving steel consumption, an...

AI Technical Summary

Problems solved by technology

Due to the high-strength steel bars produced by the micro-alloying hot rolling process have good physical properties, such as elongation, bending properties, weldability, good shock resistance and low strain aging, the process mechanical properties are stable, and there is no need for existing steelmaking There are too many adjustments to the rolling process, so the domestic steel mills currently produce HRB500 high-strength steel bars mainly using the vanadium-nitrogen micro-alloyed hot rolling process; The precipitation-strengthening effect has not been fully exerted, resulting in the waste of some V resources; the existing process has a large amount of vanadium-nitrogen alloy added and high cost, which squeezes the profit margin of the enterprise, which is not conducive to the development of HRB500 vanadium-nitrogen high-strength steel bars. Production and promotion of applications