Steel plate with low welding crack sensitivity and production method thereof

Abstract

The invention discloses a low-welding crack sensitivity steel board and manufacturing method, which comprises the following parts: not more than 0.07% C, 0.15-0.40% Si, 1.00-1.60% Mn, not more than 0.015% P, not more than 0.010% S, not more than 0.30% Cu, not more than 0.50% Ni, not more than 0.30% Cr, not more than 0.30% Mo, not more than 0.08% V, not more than 0.08% Nb, 0.010-0.020% Ti, not more than 0.003% B, Fe and inevitable impurity. The invention is characterized by the following: (1)displaying lower welding crack sensitivity component with Pcm not more than 0.20%; (2)mating the strength and flexibility reasonably with fitful yielding ratio; (3)making the price and property of the steel board superior to the congeneric import product; (4)making the maximum breadth of steel board to 4000mm; (5)simplifying the technique to ensure higher flatness without quenching water.

Description

technical field

[0001] The invention relates to a WDB620 steel plate with low welding crack sensitivity, and also relates to a production method of the steel plate. Background technique

[0002] At present, the 60Kg grade low-welding crack-sensitive high-strength steel produced by domestic and foreign hydropower station penstocks is delivered in a quenched and tempered state (quenching + tempering). , It is also clearly stipulated in the bidding documents of the materials: the delivery state of the steel plate selected for the high-strength steel pipe is the quenched and tempered state (quenching + tempering), or the quenched and tempered steel clearly designated as the XX grade, typically Wuhan Iron and Steel Company 07MnCrMoVR and SM570Q produced according to GB150 and JIS G3106 standards, and NK-HITEN590U2, NK-HITEN610U2 and other steel plates produced by NKK Corporation of Japan according to enterprise standards, have a low-C tempered martensite structure after quenching...