Yield strength 225MPa-level earthquake-resistant construction steel and production method thereof

Abstract

The invention discloses yield strength 225MPa-level earthquake-resistant construction steel and a production method thereof. The steel comprises the following chemical compositions in percentage by weight: 0.01 to 0.05 percent of C, 0.01 to 0.04 percent of Si, 0.20 to 0.70 percent of Mn, less than or equal to 0.010 percent of P, less than or equal to 0.005 percent of S, 0.002 to 0.007 percent of Mg, 0.001 to 0.003 percent of N, 0.005 to 0.015 percent of Re, less than or equal to 0.070 percent of Ti, less than or equal to 0.020 percent of Nb, less than or equal to 0.0520 percent of Al, and the balance of Fe and inevitable impurities. The production method for the earthquake-resistant construction steel comprises the following steps of hot metal desulphurization, converter blowing, vacuum treatment, continuous casting, hot rolling, cooling, and the like. When the yield strength of the steel products exceeds 245MPa, a step of annealing treatment is added after the cooling step. Experiments prove that the yield strength 225MPa-level earthquake-resistant construction steel has the characteristics of low yield strength, high elongation and excellent impact toughness, and the production method has the advantages of simple process and low production cost.

Description

technical field [0001] The invention relates to building steel, in particular to an anti-seismic building steel with a yield strength of 225 MPa and a production method thereof. Background technique [0002] With the development of steel structure construction, improving the seismic performance of steel structure has become one of the necessary measures to ensure the safety of buildings. In the seismic design of steel structure buildings, the energy generated by the earthquake can be absorbed by the plastic deformation of the steel structure, which requires that the steel used in the building has a lower yield strength, better plastic deformation capacity and good elongation. [0003] Before the present invention, the Chinese Invention Patent Publication No. 200710046076.8 introduced a steel plate with an extremely low yield point and a manufacturing method thereof. The chemical composition of the steel plate is (mass percentage): C: 0.006-0.018%, Si≤0.10%, Mn: 0.10-0.30%, ...

AI Technical Summary

Problems solved by technology

However, the steels disclosed in these two patents have complex chemical compositions, high content of alloying elements, high content of impurities in the steel plate, poor weather resistance and weldability

Moreover, their production alloying costs are high, and the production process is complicated, which cannot better meet the needs of large-scale production.

Images