Clean corrosion-resistant steel for ocean engineering and manufacturing method thereof

Abstract

The invention relates to clean corrosion-resistant steel for ocean engineering and a manufacturing method thereof. The clean corrosion-resistant steel comprises the following chemical components in percentage by weight: 0.01-0.03% of C, 0.28-0.95% of Si, 0.10-0.50% of Mn, 0.010-0.10% of P, 0.10-0.90% of Ni, 0.05-0.25% of Cu, not more than 0.006% of S, not more than 0.005% of Nb, not more than 0.005% of V and not more than 0.005% of Ti, wherein the sum of Cu and Ni is not less than three times of the C content and is not more than 1.15%, and the sum of Ni and Mn is not less than 1.5 times of the Cu content and is not more than 1.28%. The manufacturing method comprises the following steps of: smelting, carrying out vacuum treatment and continuously casting; heating and uniformly heating cast blank; continuously rolling to manufacture finished-product steel plates; and naturally cooling down to room temperature. According to the clean corrosion-resistant steel for the ocean engineering and the manufacturing method thereof, disclosed by the invention, on the premise of meeting mechanical property of the steel of an ocean structure, the seawater corrosion resistance is improved by at least 35%, the cleanliness of the steel is high (the number of impurity grains observed under a metallographic microscope of 100 times is not more than 5), and the cold and hot processing properties are excellent.

Description

technical field [0001] The invention relates to a corrosion-resistant steel material, in particular to a clean corrosion-resistant marine engineering steel and a production method thereof. Background technique [0002] The service life of steel structure projects such as offshore drilling platforms, ocean-going ships, and cross-sea bridges is significantly lower than that of inland steel structure projects due to the corrosive environment of seawater and ocean atmosphere. Corrosion is the first factor in the failure of steel structure projects. In order to improve the service life, often Spray thick anti-corrosion paint on the steel surface, but it increases the weight of the steel structure itself, which is not conducive to construction and transportation. Moreover, the steel surface paint is easy to scratch during the construction process of steel structure assembly, forming a local source of corrosion, and it is not easy to be found. After a certain time it can have catas...

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Problems solved by technology

[0004] The problem to be solved by the present invention is that the cleanliness is not enough to cause poor seawater corrosion resistance. It provides a method that can improve the seawater corrosion resistance by at least 35% under the premise of satisfying the mechanical properties of steel for marine structures, and the cleanliness of the steel Good clean corrosion resistant steel for marine engineering and method for producing the same

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