Title:
MANUFACTURE OF PC STEEL BAR OF HIGH STRENGTH
Document Type and Number:
Japanese Patent JP3468828
Kind Code:
B2
Abstract:
PURPOSE: To provide a manufacturing method of a PC steel bar excellent in the delayed cracking resistance and the spot weldability.
CONSTITUTION: The steel having the composition consisting of 0.15-0.4% C, 0.05-2% Si, 0.2-2% Mn, 0.005-0.1% Al, ≤0.015% P, ≤0.015% S, and one or two or more kinds of Ti, B, Cr, Mo, Ni, Cu, V and Nb as necessary, and the balance Fe and inevitable impurities with PCM limited in the range of 0.20-0.45% where PCM(%)=C+Si/30+(Mn+Cr+Cu)/20+Ni/60+Mo/15+V/10+5B is wire drawn under the prescific condition, and heat treated under the specific conditions to obtain the structure consisting of a specific martensite and ferrite. Then, the steel is wire drawn under the specific conditions, and heat treated under the specific conditions.
Inventors:
Toshizo Tarui
Michiaki Tateyama
Michiaki Tateyama
Application Number:
JP7101494A
Publication Date:
November 17, 2003
Filing Date:
April 08, 1994
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
C21D8/08; C22C38/00; C22C38/06; (IPC1-7): C21D8/08; C22C38/00; C22C38/06
Domestic Patent References:
| JP1298116A | ||||
| JP5287450A | ||||
| JP2240244A | ||||
| JP61270355A | ||||
| JP55119134A |
Other References:
【文献】特許3348187(JP,B2)
【文献】特許3348188(JP,B2)
【文献】特許3348189(JP,B2)
【文献】特許3348188(JP,B2)
【文献】特許3348189(JP,B2)
Attorney, Agent or Firm:
Tachio Chanogi (1 outside)
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