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:
Apr. 04, 2017
Filed:
Sep. 18, 2014
Nippon Steel & Sumitomo Metal Corporation, Chiyoda-ku, Tokyo, JP;
Hatsuhiko Oikawa, Tokyo, JP;
Hideki Hamatani, Tokyo, JP;
Masafumi Azuma, Tokyo, JP;
Noriyuki Suzuki, Tokyo, JP;
Fuminori Watanabe, Tokyo, JP;
Naoki Maruyama, Tokyo, JP;
Hiroyuki Kawata, Tokyo, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
Provided is a spot welded joint () which includes at least one thin steel plate with a tensile strength of 750 MPa to 1850 MPa and a carbon equivalent Ceq of equal to or more than 0.22 mass % to 0.55 mass % and in which a nugget () is formed in an interface of the thin steel plates (A,B). In a nugget outer layer zone, a microstructure consists of a dendrite structure in which an average value of arm intervals is equal to or less than 12 μm, an average grain diameter of carbides contained in the microstructure is 5 nm to 100 nm, and a number density of carbides is equal to or more than 2×10/mm.