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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.:

US 10844920 B1

PDFFull Text
Date of Patent:
Nov. 24, 2020

Filed:

Sep. 05, 2016

Spring steel wire and spring

Applicant:

Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;

Inventors:

Shinya Teramoto, Tokyo, JP;

Hiroshi Yarita, Narashino, JP;

Shouichi Suzuki, Narashino, JP;

Assignee:

NIPPON STEEL CORPORATION, Tokyo, JP;

Attorney:

Birch, Stewart, Kolasch & Birch, LLP

Primary Examiner:

Jie Yang

Int. Cl.
CPC ...
C21D 9/02 (2006.01); F16F 1/02 (2006.01); C22C 38/06 (2006.01); C21D 8/06 (2006.01); C22C 38/26 (2006.01); C22C 38/20 (2006.01); C21D 1/48 (2006.01); C21D 6/00 (2006.01); C22C 38/02 (2006.01); C22C 38/34 (2006.01); C22C 38/00 (2006.01); C21D 9/52 (2006.01); C22C 38/22 (2006.01); C22C 38/28 (2006.01); C22C 38/04 (2006.01); C21D 1/25 (2006.01); C22C 38/18 (2006.01); C22C 38/24 (2006.01); C22C 38/32 (2006.01); C22C 38/60 (2006.01);
U.S. Cl.
CPC ...
F16F 1/02 (2013.01); C21D 1/25 (2013.01); C21D 1/48 (2013.01); C21D 6/002 (2013.01); C21D 6/008 (2013.01); C21D 8/065 (2013.01); C21D 9/02 (2013.01); C21D 9/525 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/18 (2013.01); C22C 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/24 (2013.01); C22C 38/26 (2013.01); C22C 38/28 (2013.01); C22C 38/32 (2013.01); C22C 38/34 (2013.01); C22C 38/60 (2013.01); C21D 9/52 (2013.01); C21D 2211/004 (2013.01); C21D 2211/008 (2013.01);
Abstract

A spring steel wire includes, by mass %, C: 0.40% to 0.75%, Si: 1.00% to 5.00%, Mn: 0.20% to 2.00%, P: 0.0001% to 0.0500%, S: 0.0001% to 0.0500%, Cr: 0.50% to 3.50%, Al: 0.0005% to 0.0500%, N: 0.0020% to 0.0100%, Mo: 0% to 2.00%, V: 0% to 0.50%, W: 0% to 0.50%, Nb: 0% to 0.100%, Ti: 0% to 0.100%, Ca: 0% to 0.0100%, Mg: 0% to 0.0100%, Zr: 0% to 0.1000%, B: 0% to 0.0100%, Cu: 0% to 1.00%, Ni: 0% to 3.00%, and a remainder consisting of Fe and impurities. A structure includes, by area radio, tempered martensite of 90% or more. The prior austenite grain size number is No. 12.5 or higher. The presence density of iron-based carbide having an equivalent circle diameter ranging from 0.15 μm to 0.50 μm ranges from 0.40 pieces/μmto 2.00 pieces/μm.

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