A kind of 160mm thick q235c low compression bit thick steel plate and its preparation method

Abstract

The invention discloses a Q235C super-thick steel plate having a thickness of 160mm and low compression ratio and a preparation method of the steel plate. The Q235C super-thick steel plate comprises the following components in percentage by weight: 0.10-0.17% of C, 0.10-0.35% of Si, 0.80-1.40% of Mn, less than or equal to 0.018% of P, less than or equal to 0.0050% of S, 0.020-0.050% of Alt, 0.28-0.34% of Ceq and the balance of Fe and unavoidable impurities. During rolling, the heating temperature of a continuous casting billet having a thickness of 320mm is 1140-1240 DEG C, the heating time of the billet is 300-400 minutes, the temperature of a soaking zone is 1130-1230 DEG C, the soaking time is at least 70 minutes, and the tapping temperature is 1130-1230 DEG C; a one-stage controlled rolling is adopted, greatest reduction is adopted in each pass, the finishing rolling temperature is 800-900 DEG C, and a swing-type reciprocating water-cooled process is used after the rolling. By the preparation method, on the premise that the compression ratio is only 2: 1, a carbon structural steel having a thickness of 160mm and the yield strength being greater than 195MPa can be obtained through rolling, the production pace is quick, the strong applicability is achieved and the Q235C super-thick steel plate has the advantages of excellent lamellar tearing resistance, no need of heat treatment and low production cost.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and relates to a carbon structural steel plate and a preparation method thereof, in particular to a 160mm thick Q235C low compression bit thick steel plate and a preparation method thereof. Background technique [0002] With the continuous increase of my country's infrastructure construction projects, the market demand for extra-thick plates (greater than or equal to 60mm thick) is increasing. The production of extra-thick steel plates in my country cannot meet the needs of the market, and it still needs to be imported from abroad every year, especially some high-performance extra-thick steels, which have high added value. [0003] Extra-thick plates are used in important components, which have high requirements for product service safety, which requires that 160mm thick Q235C steel plates must have: ① Higher strength and toughness, yield strength> 195MPa, tensile strength 370~500MPa, meet ...

AI Technical Summary

Problems solved by technology

[0004] When producing Q235C steel plates with a thickness specification > 150mm and a yield strength of 195MPa or more, major extra-thick plate manufacturers generally use steel ingots as raw materials to produce extra-thick steel plates, resulting in low yield, harsh production environment, and slow production cycle.

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