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:
Jul. 15, 2003
Filed:
Dec. 05, 2001
Applicant:
Inventor:
Alkan Goecmen, Baden-Daettwil, CH;
Assignee:
Alstom (Switzerland) Ltd, Baden, CH;
Primary Examiner:
Int. Cl.
CPC ...
C22C 3/842 ; C22C 3/844 ; C22C 3/846 ; C22C 3/850 ; C22C 3/852 ;
U.S. Cl.
CPC ...
C22C 3/842 ; C22C 3/844 ; C22C 3/846 ; C22C 3/850 ; C22C 3/852 ;
Abstract
The invention relates to a transformation controlled nitride precipitation hardening heat-treatable steel with the following composition (data in wt. %): 15-18 Cr, max. 0.5 Mn, 4-10 Ni, max. 15 Co, max. 4 W, max. 4 Mo, 0.5-1 V, at least one of Nb, Ta, Hf and Zr totaling between 0.001-0.1, 0.001-0.05 Ti, max. 0.5 Si, max. 0.05 C, 0.13-0.25 N, max. 4 Cu, rest iron and usual impurities, under the condition that the weight ratio of vanadium to nitrogen V/N is in the range between 3.5 and 4.2. The invention also relates to a heat treatment process for this steel. Very good strength, ductility and also corrosion resistance can be attained.