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:
Jan. 31, 1984
Filed:
Sep. 24, 1982
Lars A Norstrom, Hagfors, SE;
Uddeholms Aktiebolag, Hagfors, SE;
Abstract
A steel with good weldability and hardenability, a yield point of at least 600 MPa, a rupture limit of at least 900 MPa at room temperature and an impact toughness of at least 40 Joule at -20.degree. C., has the following chemical composition as % by weight: C: 0.03-0.07 Si: 0.10-1 Mn: 1.2-2.5 Cr: 1.8-3 Ni: 1.5-3 Mo: max 0.5 Nb, V, Ti total 0-0.10 with the remainder mainly only iron and impurities in normal amounts. The best impact toughness in achieved when the ratio Mn/Cr is about 2/3 or 0.6. The total content of Mn+Cr is, in accordance with a preferred embodiment, between 3 and 5, suitably between 3.5 and 4.5%. The steel is particularly suitable for anchor chains for e.g. off-shore oil drilling platforms. A recommended heat treatment after welding includes normalizing at 800.degree.-1000.degree. C., cooling to room temperature and duplex annealing.