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. 15, 2015
Filed:
Mar. 26, 2009
Yuusuke Oikawa, Tokyo, JP;
Hiroshi Urashima, Tokyo, JP;
Shinji Tsuge, Tokyo, JP;
Hiroshige Inoue, Tokyo, JP;
Ryo Matsuhashi, Tokyo, JP;
Yuusuke Oikawa, Tokyo, JP;
Hiroshi Urashima, Tokyo, JP;
Shinji Tsuge, Tokyo, JP;
Hiroshige Inoue, Tokyo, JP;
Ryo Matsuhashi, Tokyo, JP;
Abstract
The present invention provides a lean duplex stainless steel able to suppress the drop in corrosion resistance and toughness of a weld heat affected zone comprising, by mass %, C: 0.06% or less, Si: 0.1 to 1.5%, Mn: 2.0 to 4.0%, P: 0.05% or less, S: 0.005% or less, Cr: 19.0 to 23.0%, Ni: 1.0 to 4.0%, Mo: 1.0% or less, Cu: 0.1 to 3.0%, V: 0.05 to 0.5%, Al: 0.003 to 0.050%, O: 0.007% or less, N: 0.10 to 0.25%, and Ti: 0.05% or less, having a balance of Fe and unavoidable impurities. An Md30 value is 80 or less, an Ni-bal is −7.1 to 4, an austenite phase area percentage is 40 to 70%, and a 2×Ni+Cu is 3.5 or more: Md30=551−462×(C+N)−9.2×Si−8.1×Mn−29×(Ni+Cu)−13.7×Cr−18.5×Mo−68×Nb; Ni-bal=(Ni+0.5Mn+0.5Cu+30C+30N)−1.1(Cr+1.5Si+Mo+W)+8.2 and N(%)≦0.37+0.03×(Ni-bal).