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:
Feb. 10, 2009
Filed:
Nov. 14, 2003
Masayuki Hashimura, Muroran, JP;
Atsushi Mizuno, Muroran, JP;
Kenichiro Naito, Tokyo, JP;
Hiroshi Hagiwara, Tokyo, JP;
Kohichi Isobe, Muroran, JP;
Hiroshi Hirata, Muroran, JP;
Masayuki Hashimura, Muroran, JP;
Atsushi Mizuno, Muroran, JP;
Kenichiro Naito, Tokyo, JP;
Hiroshi Hagiwara, Tokyo, JP;
Kohichi Isobe, Muroran, JP;
Hiroshi Hirata, Muroran, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
The present invention provides steel superior in machinability comprised of, by wt %, C: 0.005 to 0.2%, Si: 0.001 to 0.5%, Mn: 0.2 to 3.0%, P: 0.001 to 0.2%, S: 0.03 to 1.0%, T.N: 0.002 to 0.02%, T.O: 0.0005 to 0.035%, and the balance of Fe and unavoidable impurities, said steel satisfying one or both of Mn/S in the steel being 1.2 to 2.8 or an area ratio of pearlite over a grain size of 1 μm in a microstructure of the steel being not more than 5%.