Title:
NON-HEAT TREATED STEEL EXCELLENT IN YIELD STRENGTH AND HAVING HIGH TOUGHNESS
Document Type and Number:
Japanese Patent JP2780628
Kind Code:
B2
Abstract:
PURPOSE: To produce a non-heat treated steel excellent in yield strength and having high toughness.
CONSTITUTION: This steel has a composition consisting of, by weight, 0.20-0.30% C, 0.05-1.00% Si, 1.00-3.00% Mn, ≤0.020% S, 1.00-3.00% Cr, 0.05-0.20% V, 0.005-0.030% sol.Al, and the balance Fe with inevitable impurities and containing, if necessary, 0.005-0.080% Nb and/or 0.005-0.050% Ti and satisfying inequality 1.2≤C%+(1/10)Si%+(1/5)Mn%+(5/22)Cr%+(33/20)V%-(5/7)S%≤1.5. Further, this steel has a bainitic structure in which the area ratio of pro-eutectoid ferrite is regulated to ≤10% and A type inclusions (JISG0202) of ≤2.0μm average diameter are contained by ≥20pieces/mm2 by existence frequency.
Inventors:
Satoshi Kakizaki
Yoshihiko Kamata
Kazuhiko Nishida
Yoshihiko Kamata
Kazuhiko Nishida
Application Number:
JP2379894A
Publication Date:
July 30, 1998
Filing Date:
January 26, 1994
Export Citation:
Assignee:
SUMITOMO METAL INDUSTRIES,LTD.
International Classes:
C22C38/00; C22C38/24; (IPC1-7): C22C38/00; C22C38/24
Attorney, Agent or Firm:
Terutaka Hogami (1 person outside)