Title:
655 MPa CLASS MARTENSITIC STAINLESS STEEL EXCELLENT IN TOUGHNESS AND METHOD FOR PRODUCTION THEREOF
Document Type and Number:
WIPO Patent Application WO/2006/064553
Kind Code:
A1
Abstract:
A steel which has a chemical composition, in wt %, C: 0.005 to 0.05 %, Si: 0.1 to 0.5 %, Mn: 0.1 to 2.0 %, P: 0.05 % or less, S: 0.005 % or less, Cr: 10.0 to 12.5 %, Mo: 0.1 to 0.5 %, Ni: 1.5 to 3.0 %, N: 0.02 % or less, Al: 0.01 to 0.1 %, provided that an FI value defined by FI = Cr + Mo - Ni -30(C + N) is 5.00 to 8.49, and the balance: substantially iron. A method for producing a martensitic stainless steel for a seamless pipe, which comprises subjecting the above steel to a hot rolling, followed by cooling, and re-heating the resultant steel to a temperature in the range of 780 to 960&ring C, followed by quenching, and then tempering the resultant steel in the range of 550 to 650&ring C. A martensitic stainless steel produced by the above method is suitable to the use under a high CO2 circumstance, has a yield strength of 655 to 758 MPa and high toughness, and is excellent in economical efficiency.
Inventors:
HASHIZUME SHUJI
MINAMI YUSUKE
ONO TATSUO
MINAMI YUSUKE
ONO TATSUO
Application Number:
PCT/JP2004/018710
Publication Date:
June 22, 2006
Filing Date:
December 15, 2004
Export Citation:
Assignee:
NKKTUBES (JP)
HASHIZUME SHUJI
MINAMI YUSUKE
ONO TATSUO
HASHIZUME SHUJI
MINAMI YUSUKE
ONO TATSUO
International Classes:
C22C38/00; C21D6/00; C21D8/02; C22C38/58
Foreign References:
| JP2002241902A | 2002-08-28 | |||
| JP2002180210A | 2002-06-26 | |||
| JP2002309349A | 2002-10-23 | |||
| JP2000328202A | 2000-11-28 | |||
| JP2000024783A | 2000-01-25 |
Attorney, Agent or Firm:
Tsukuni, Hajime (22-12 Toranomon 1-chome, Minato-k, Tokyo 01, JP)
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