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:
Sep. 11, 2012
Filed:
Jan. 13, 2009
Masaharu Hatano, Tokyo, JP;
Akihiko Takahashi, Tokyo, JP;
Masaharu Hatano, Tokyo, JP;
Akihiko Takahashi, Tokyo, JP;
Abstract
The present invention provides high purity ferrite stainless steel able to reduce deterioration in surface conditions due to pitting corrosion or rusting or other corrosion to an extent no different from SUS304 or better without inviting a drop in manufacturability or workability and without relying on the addition of rare elements, and a method of production of the same, that is, ferritic stainless steel containing, by mass %, C: 0.01% or less, Si: 0.01 to 0.20%, Mn: 0.01 to 0.30%, P: 0.04% or less, S: 0.01% or less, Cr: 13 to 22%, N: 0.001 to 0.020%, Ti: 0.05 to 0.35%, Al: 0.005 to 0.050%, Sn: 0.001 to 1%, and a balance of Fe and unavoidable impurities to which Sn is added to modify the passive film and improve the corrosion resistance. To improve the effect of modification of the passive film by the addition of Sn, after the final annealing, the steel is held in the 200 to 700° C. temperature range for 1 minute or more.