Title:
MANUFACTURE OF ROLLED SHAPE STEEL EXCELLENT IN TOUGHNESS
Document Type and Number:
Japanese Patent JP2601961
Kind Code:
B2
Abstract:
PURPOSE: To improve the material properties and toughness of steel by subjecting molten steel having a specified compsn. to preliminary deoxidizing treatment to control the amt. of dissolved oxygen, thereafter adding Al thereto, regulating the amt. of Al executing casting and subjecting it to hot rolling.
CONSTITUTION: Molten steel constituted of, by weight, 0.04 to 4.20% C, 0.05 to 0.50% Si, 0.8 to 1.8% Mn, 0.05 to 0.20% V, 0.004 to O.015% N, 0.005 to 0.025% Ti and the balance Fe with inevitable impurities is subjected to preliminary deoxidizing treatment to regulate the amt. of dissolved oxygen to 0.003 to 0.015% and to highly purify the molten steel. Metallic aluminum or ferroaluminum is added to the above molten steel, which is oxidized to control the amt. of oxygen to be added to 0.005 to 0.15% as well as so as to satisfy the relationship of -0.004≤Al%-1.10%≤0.006 to the amt. of dissolved oxygen, and casting is executed. This slab is reheated to 1100 to 1300°C, is subjected to hot rolling and is finished with the rolling at 750 to 1050°C to manufacture the shape steel.
Inventors:
Hiroichi Yamamoto
Yasushi Takeshima
Yasushi Takeshima
Application Number:
JP29553791A
Publication Date:
April 23, 1997
Filing Date:
November 12, 1991
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
C21C7/04; B22D11/00; B22D11/10; B22D11/108; B22D11/12; C21C7/00; C21C7/06; C21D8/00; C21D9/00; C22C38/00; C22C38/14; (IPC1-7): B22D11/10; B22D11/00; B22D11/12; C21C7/00; C21D8/00; C22C38/00; C22C38/14
Domestic Patent References:
| JP2220735A |
Attorney, Agent or Firm:
Tomoyuki Yathata (1 outside)