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:
Aug. 16, 1977
Filed:
May. 14, 1976
Yoshihiro Yamaguchi, Ashiya, JA;
Takashi Shimohata, Akashi, JA;
Sodai Kita, Kobe, JA;
Yoshihide Fuchino, Kobe, JA;
Tsugio Kaneda, Akashi, JA;
Masashi Kawauchi, Kobe, JA;
Sadayashi Furusawa, Kobe, JA;
Shuzi Iwata, Kobe, JA;
Kobe Steel, Ltd., Kobe, JA;
Abstract
This invention relates to a free-cutting steel that is used as a material for mechanical construction members be manufactured by machining as well as cold working. There has been proposed resulfurized free-machining steels containing large amounts of sulfur to improve the machinability, as well as resulfurized free-machining steels containing sulfur and zirconium to improve machinability and cold workability. None of these steels, however, simultaneously satisfy the machinability cold workability and mechanical properties required of steels used for the construction of machines. The present invention provides a steel comprising 0.08 to 0.6% of carbon, 0.35% or less of silicon, 0.3 to 1.5% of manganese, 0.04 to 0.15% of sulfur, 0.010 to 0.05% of aluminum, 0.01 to 0.08% of niobium, 0.008% or less of oxygen, 0.008% or less of nitrogen, wherein the amount of zirconium being 0.2 to 1.2 in terms of (Zr% -2.9x 0% -6.5x N%)/S%, the steel has a refined grain size and controlled sulfide morphology, and exhibits improved machinability, cold workability and mechanical properties.