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:
Feb. 20, 1996
Filed:
Apr. 18, 1994
Katsuaki Fukushima, Shimane, JP;
Toshio Okuno, Yasugi, JP;
Masakazu Ito, Kasugai, JP;
Keizo Takeuchi, Handa, JP;
Toshiaki Terada, Okazaki, JP;
Hitachi Metals, Ltd., Tokyo, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A high-strength stainless steel for use as a material of a fuel injection nozzle or a fuel injection needle of an internal combustion engine. The stainless steel is an as annealed martensitic stainless steel which exhibits a hardness not less than HRC 58 after quenching and tempering heat-treatment. The limit swaging ratio of said as annealed martensitic stainless steel is not less than 75%. The hardness of said as annealed martensitic stainless steel is not higher than HB 157. Preferably, the number of carbides having sizes of 0.2 .mu.m or less occupies not more than 50% of the total carbides, and wherein the limit swaging ratio of said as annealed martensitic stainless steel is not less than 75% or the hardness of said as annealed martensitic stainless steel is not higher than HB 157. Preferably, the stainless steel has a chemical composition containing, by weight: 0.4 to 0.6% of C; not more than 0.5% of Si; not more than 0.5% of Mn; 8.0 to 13.0% of Cr; 0.1 to 2.0% of one or both of W and Mo in terms of W/2+Mo; one or both of 0.05 to 1.0% of one or both of Nb and V in terms of Nb/2+V, and 0.2 to 2.0% of Co; and the balance substantially Fe and incidental impurities.