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. 22, 1995
Filed:
Jun. 30, 1993
Tohru Arai, Aichi, JP;
Kazuyuki Nakanishi, Aichi, JP;
Hiromasa Takeda, Aichi, JP;
Hideo Tachikawa, Aichi, JP;
Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi, JP;
Abstract
A nitride or carbonitride layer is formed on the surface of a metal material as follows: A treating agent composed of a refractory powder of alumina or the like and a powder of a metal for forming a nitride or a carbide or an alloy thereof is disposed in a fluidized bed furnace; the treating agent is fluidized to form a fluidized bed by introducing an inert gas; the fluidized bed furnace is heated to a temperature of not higher than 700.degree. C.; an activator of a halogenated ammonium salt is intermittently supplied into the fluidized bed at a rate of 0.001 to 5 wt %/hour based on the total amount of the treating agent; and the metal material to be treated is disposed in the fluidized bed during or after any of the above steps. For example, a nitride layer composed of only a metal for forming a nitride which contains almost no Fe--N is formed on the surface of iron steel even at a temperature as low as not higher than 700.degree. C. The layer is very hard and efficient in wear resistance, and the toughness of the base metal is hardly lowered.