YP500MPa-level thick steel plate with excellent low-temperature toughness and manufacturing method thereof

Abstract

The invention relates to a TMCP-type YP500MPa-level thick steel plate with excellent low-temperature toughness which comprises the following chemical components by weight: 0.010-0.08% of C, 0.005-0.6% of Si, 0.5-2.50% of Mn, not more than 0.015% of P, not more than 0.005% of S, 0.010-0.12% of Nb, 0.005-0.03% of Ti, less than 0.120% of V, not more than 1.50% of Cr, not more than 0.80% of Mo, not more than 1.2% of Cu, not more than 1.60% of Ni, not more than 0.06% of Al, not more than 0.01% of Ca, 0.003-0.008% of N, not more than 0.0025% of B, not more than 0.008% of O, and the balance of Fe and inevitable impurity elements. In the manufacturing process, a heating temperature of a continuous casting blank is 1100-1250 DEG C; a rolling temperature of a recrystallization zone is 920-1170 DEG C; a rolling temperature of a non-recrystallization zone is 680-910 DEG C; a finish rolling compression ratio is not less than 2 T, wherein T is a finished product thickness; a cooling speed is not less than 5 DEG C / s, and a finally cooling temperature is 300-600 DEG C. A TMCP-type YP500MPa-level thick steel plate with excellent low-temperature toughness is obtained.

Description

technical field [0001] The invention relates to a production method of a TMCP type YP500MPa grade steel plate with excellent low-temperature toughness, which is suitable for ships and ocean platforms. Background technique [0002] With the development of the shipbuilding industry, the requirements for the performance of steel for hull structures are getting higher and higher. With the development of the steel industry, the output of steel plates with high strength, excellent toughness, weldability and high surface quality is constantly increasing, but The development of the shipbuilding industry towards large-scale, lightweight and energy-saving, and the service requirements of ships in some special environments make the requirements for material properties more stringent. [0003] Classification societies of various countries have different technical requirements for ship plate steel, but the difference is not significant. According to the material specifications of the cl...

AI Technical Summary

Problems solved by technology

Compared with C in this patent at 0.03% to 0.08%, this patent adopts a higher content range of C at 0.05% to 1.0%, which affects the low temperature toughness level of thick steel plates, and this patent has a certain relationship between Ti / N and chemical elements. Strict restrictions:

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