HRB500E fine grain anti-seismic steel bar and production method thereof

Abstract

The invention provides an HRB500E fine grain anti-seismic steel bar which is characterized by comprising the following chemical compositions: C: 0.20-0.25 percent by weight, Si: 0.20-0.45 percent by weight, Mn: 1.35-1.60 percent by weight, Nb: not more than 0.022 percent by weight, S: not more than 0.045 percent by weight, P: not more than 0.045 percent by weight and the balance of Fe and inevitable impurities. The production method thereof only needs to add a very small amount of ferro-niobium and a small amount of nitride intensifier in the steel-making process and then uses the controlled cooling method after rolling in the steel rolling production process to obtain the fine grain anti-seismic steel bar with stable mechanical performances and first-grade anti-seismic qualified rate of being more than 98.0 percent, thereby solving the welding effect of the fine grain high-tensile steel bar and other problems; in addition, the Si content in steel is controlled at a lower level, the consumption of silicon iron is significantly reduced; compared with the prior art, the adding amount of micro-alloy is greatly reduced, thereby being conductive to protecting rare mineral resources and reducing cost.

Description

technical field [0001] The invention relates to a fine-grain anti-seismic steel bar, in particular to a HRB500E fine-grain anti-seismic steel bar and a production method thereof, belonging to the technical field of metal material processing and forming. Background technique [0002] Hot-rolled ribbed steel bar is the main reinforcement material of reinforced concrete building structure, which bears tensile and compressive stress and strain in the structure, high cycle or low cycle fatigue effect, high temperature or cold brittle effect, physical or chemical corrosion, steel bar reprocessing effect , Various loads such as welding, mechanical connection, bending or straightening, etc., enable concrete to meet various functional requirements and have a wide range of applications. With the emergence of high-rise, long-span, earthquake-resistant, low-temperature-resistant, and fire-resistant building structures, steel bars are required to have higher comprehensive properties such...

AI Technical Summary

Problems solved by technology

But the main problems existing in the existing production process are: 1. At present, the price of microalloys such as vanadium alloys and ferroniobium is relatively high, and the amount of microalloys added in the steelmaking process is too large, resulting in high production costs and completely occupying the enterprise Profit margins are not conducive to improving the competitiveness of enterprises

2. Due to the high cost of producing HRB500 and HRB500E high-strength steel bars by conventional micro-alloying process, the production motivation of enterprises is insufficient, and the output cannot be scaled up, so it is not conducive to the promotion and application of HRB500 and HRB500E steel bars

3. The reserves of ferroniobium and vanadium-nitrogen alloy mineral resources, which are important national strategic reserves, are very limited. The conventional production process has greatly increased the consumption of micro-alloyed ferroniobium and vanadium-nitrogen alloys, and the reserves of ferroniobium and vanadium-nitrogen alloy mineral resources have declined sharply , not conducive to the protection of rare mineral resources and the ecological environment