STEEL EXCELLENT IN TOUGHNESS AT WELD HEAT-AFFECTED ZONE

Title:

STEEL EXCELLENT IN TOUGHNESS AT WELD HEAT-AFFECTED ZONE

Document Type and Number:

Japanese Patent JP3408385

Kind Code:

B2

Abstract:

PROBLEM TO BE SOLVED: To obtain a steel excellent in toughness at low temp. in a weld heat- affected zone by providing a specific composition and specifying the number of oxides and double oxides of Ti and Mg.
SOLUTION: The steel has a composition consisting of, by weight, 0.01-0.15% C, ≤0.6% Si, 0.5-2.5% Mn, ≤0.030% P, ≤0.005% S, 0.005-0.025% Ti, ≤0.02% Al, 0.0001-0.0010% Mg, 0.001-0.004% O, 0.001-0.006% N, and the balance Fe with inevitable impurities and contains the oxides and double oxides of Ti and Mg, with 0.001-5.0μm grain size, by ≥40 pieces/mm2. By this method, steel materials (thick steel plate, hot coil, shape steel, steel tube, etc.), excellent in toughness at low temp. in a weld heat-affected zone (HAZ), can be obtained.

Inventors:

Takuya Hara
Hitoshi Asahi
Hiroshi Tamehiro
Ryuji Uemori
Naoki Saito

Application Number:

JP33617496A

Publication Date:

May 19, 2003

Filing Date:

December 16, 1996

Export Citation:

Click for automatic bibliography generation Help