High-performance hot-rolled H profile steel resisting atmosphere corrosion and preparation method thereof

Abstract

The invention aims to solve the defects of welding and strength performances in traditional weather-resistant H profile steel, and provides high-performance hot-rolled H profile steel resisting atmosphere corrosion and a preparation method thereof. The H profile steel comprises the following chemical components: C, Si, Mn, Cr, Cu, Ni, Mo, Sb, Als, not more than 0.025% of P, not more than 0.010% of S, not more than 0.0080% of N, Bs, Nb, Ti, V, Ca, and the balance of Fe and inevitable impurities; and the required atmosphere corrosion resisting index I is not less than 6.30. The preparation method is to perform air cooling or rapid cooling for a forging blank of the components after secondary rolling. The product reduces the carbon content, adds the microalloying elements of Nb and Ti, adds Ni, Mo, Cu and Cr, and also adds Sb to greatly improve the corrosion resistance in industrial-polluted atmosphere environment containing such higher pollutants as SO2; the steel structure of the product mainly adopts ferrite and ferrite+bainite; and the product has the yield strength of 235-500 MPa grade, is excellent in toughness and plasticity, is excellent in industrial-polluted atmosphere environment corrosion resistance, and can be used without coating in the industrial-polluted atmosphere environment.

Description

technical field [0001] The invention belongs to the field of iron and steel manufacturing, and particularly relates to a hot-rolled H-shaped steel with excellent atmospheric environment corrosion resistance, excellent welding performance and excellent low-temperature toughness and a preparation method thereof. Background technique [0002] The deterioration or even destruction of metal materials and their products caused by chemical or electrochemical reactions in the atmospheric environment is called atmospheric corrosion. Corrosive gases such as SO in the global atmosphere 2 , SO 3 、H 2 S, HCl, Cl 2 , CO 2 , CO, etc. have increasingly become the main killers of atmospheric corrosion, greatly accelerating the corrosion of metal materials in the atmospheric environment. SO in polluted atmosphere 2 The impact is the most serious, mainly from the waste gas from petroleum and coal combustion and the waste gas from factory production, and its solubility in aqueous solution...

AI Technical Summary

Problems solved by technology

The patented H-shaped steel has high carbon content and added B elements. Its welding performance and low-temperature impact toughness are poor, and its carbon content is in the range of peritectic steel. difficulty

Because the chemical elements that play a role in weather resistance in its composition design are only the traditional combination of Cr and Ni elements, its corrosion resistance is poor in the modern industrially polluted atmospheric environment

[0004] Patent No. ZL201310199239.1, a rolling process patent for vanadium-containing weather-resistant hot-rolled H-shaped steel with a yield strength of 500MPa, discloses a rolling process for a vanadium-containing weather-resistant hot-rolled H-shaped steel with a yield strength of 500MPa. Weather-resistant hot-rolled H-shaped steel, in terms of mass percentage, the composition ratio is C: 0.09-0.12, Si: 0.43-0.55, Mn: 1.39-1.49, P: 0.013-0.017, S: 0.011-0.016, Cu: 0.27-0.36 , Cr: 0.32~0.38, Ni: 0.25~0.32, V: 0.098~0.110, AlS: 0.014~0.023, and the rest are iron and residual trace impurities; the chemical elements that play a role in weather resistance in the composition design of this invention patent are still traditional Combination of Cu, Cr and Ni elements, its corrosion resistance performance is average in modern industrial polluted atmospheric environment, and its carbon content is in the range of peritectic steel, the continuous casting slab is easy to crack, which causes serious damage to the continuous casting slab production and welding process. great difficulty

[0005] To sum up, the shortcomings of the existing weather-resistant H-beam technology are mainly high carbon content, unreasonable ratio of alloying elements, poor corrosion resistance in industrial atmospheric environment, and poor welding performance and low-temperature toughness of steel.

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