The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 25, 2001
Filed:
Jan. 12, 2001
Applicant:
Inventors:
Mutsumi Tanida, Wakayama, JP;
Tetsuya Nakanishi, Wakayama, JP;
Assignee:
Sumitomo Metal Industries, Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C22C 3/818 ; C22C 3/860 ; C22C 3/832 ;
U.S. Cl.
CPC ...
C22C 3/818 ; C22C 3/860 ; C22C 3/832 ;
Abstract
A martensitic stainless steel for seamless steel pipes, excellent in descaling property and machinability, having the following chemical composition, by weight %; 0.025 to 0.22% of C, 10.5 to 14% of Cr, 0.16 to 1.0% of Si, 0.05 to 1.0% of Mn, 0.05% or less of Al, 0.100% or less of N, 0.25% or less of V, 0.020% or less of P, 0.004 to 0.015% of S, and the balance Fe and impurities, This steel may include 0.0002 to 0.0050% of B, and/or 0.0005 to 0.005% of Ca. In this case, the upper limit of S may be extended up to 0.018%. Preferably, Al is limited to less than 0.01%.