Off-line quenched and tempered EH960 ultrahigh-strength maritime work steel plate and manufacturing method thereof

Abstract

The invention discloses an off-line quenched and tempered EH960 ultrahigh-strength maritime work steel plate and a manufacturing method thereof. The off-line quenched and tempered EH960 ultrahigh-strength maritime work steel plate comprises the following chemical components in percentage by weight: 0.05%-0.11% of C, 0.30%-0.60% of Si, 1.40%-1.60% of Mn, less than or equal to 0.013% of P, less than or equal to 0.003% of S, 0.040%-0.065% of Nb, 0.005%-0.020% of Ti, 2.5%-3.5% of Ni, 1.1%-1.50% of Cu, 0.40%-0.50% of Mo, 0.40%-0.60% of Cr, 0.50%-0.60% of Al, less than or equal to 12 ppm of O, less than or equal to 40 ppm of N, less than or equal to 1.5 ppm of H, more than or equal to 2 of Ni / Cu, less than or equal to 6 of Ni / Al and the balance of Fe and inevitable impurities. The off-line quenched and tempered EH960 ultrahigh-strength maritime work steel plate provided by the invention is excellent in performance and appropriate in thickness, low-carbon design is adopted for the components, and according to the influence rule of alloy elements such as C, Si, Ni, Al, Mo, Cu, Nb, Mn, Ti and the like and Ni / Cu and Ni / Al on the strength, toughness and yield ratio of steel, a component foundation is laid for obtaining various properties such as ultrahigh strength, high toughness, high plasticity, low yield ratio, easiness in welding and low crack sensitivity of the product; and smelting, rolling treatment and off-line quenching and tempering production are adopted in the process, and the shape and performance of the steel plate can be considered.

Description

technical field [0001] The invention relates to a steel for ships and marine engineering and a manufacturing method thereof, in particular to an off-line quenched and tempered EH960 ultra-high-strength marine steel plate and a manufacturing method thereof. Background technique [0002] In the existing technology, some important steel types have been widely used on a large scale, but there is still a lack of platform steel with ≥500 MPa grade ultra-high strength, easy to weld, ultra-low temperature, and seawater corrosion resistance for key parts of ships and marine engineering equipment. , Extensive research and collaboration are needed to solve these problems, so as to improve the level of independent and controllable technology in the marine engineering equipment and high-tech ship industry chain, and enhance the competitiveness of marine engineering and high-tech ships. [0003] The service time of offshore platforms is 50% longer than that of ships. The steel plates used...

AI Technical Summary

Problems solved by technology

The yield strength of the steel plate needs to be improved, and the thickness of the steel plate is relatively large, so the production process has more stringent requirements

Images