Title:
CONTINUOUSLY CAST SLAB FREE FROM SURFACE CRACKING AND PRODUCTION OF NON-REFINING HIGH TENSILE STRENGTH STEEL MATERIAL USING THE SLAB
Document Type and Number:
Japanese Patent JP3719037
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a continuously cast slab free from surface cracking though VN is contained in the steel and to produce non-refining high tensile strength steel material provided with good toughness by using the continuously cast slab.
SOLUTION: The steel compsn. of the continuously cast slab is composed of the one contg., by weight, 0.05 to 0.18% C, ≤0.6% Si, 0.80 to 1.80% Mn, ≤0.030% P, ≤0.004% S, ≤0.050% Al, 0.10 to 0.50% Cu, 0.04 to 0.15% V and 0.0050 to 0.0150% N, moreover contg. one or two kinds of 0.004 to 0.030% Ti and 0.0003 to 0.0030% B in the ranges satisfying the inequality of 5.0≤wt.% V/(wt.% N-0.292×wt.% Ti-1.295×wt.% B)≤18.0, furthermore contg. one or two kinds of 0.0010 to 0.0100% Ca and 0.0010 to 0.0100% rare earth metals in the ranges satisfying the inequality of wt.% Mn×(wt.% S-0.8×(wt.% Ca-110wt.% Ca×wt.% O)-0.25×(wt.% REM-70×wt.% REM×wt.% O)×103≤1.0, and consisting of the balance iron with inevitable impurities.
Inventors:
Akio Omori
Kawabata Bunmaru
Yi Geon
Kawabata Bunmaru
Yi Geon
Application Number:
JP6275399A
Publication Date:
November 24, 2005
Filing Date:
March 10, 1999
Export Citation:
Assignee:
jfe Steel Corporation
International Classes:
C21D8/00; C21D8/02; C22C38/00; C22C38/04; C22C38/12; C22C38/14; C22C38/16; C22C38/58; (IPC1-7): C22C38/00; C21D8/00; C22C38/14; C22C38/58
Domestic Patent References:
| JP53123325A | ||||
| JP58084958A | ||||
| JP7090474A | ||||
| JP5279790A | ||||
| JP10088276A |
Attorney, Agent or Firm:
Junzo Ogawa
Morio Nakamura
Morio Nakamura