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:
Oct. 03, 1989
Filed:
Nov. 13, 1987
Abstract
A method of forming a nitride or carbonitride layer on the surface of an iron or iron alloy article, which comprises the steps of: (a) disposing in a fluidized bed furnace a treating agent comprising a refractory powder, a metal powder of at least one selected from the group consisting of chromium, vanadium, titanium and a metal containing at least one of the chromium, vanadium and titanium, and a halide powder; (b) introducing a nitrogen-containing gas into the fluidizied bed furnace; (c) heating the fluidized bed furnace; and (d) disposing the article in the fluidized bed furnace during or after the steps (a) to (c). In this method, the article is preferably treated at a temperature not higher than 650.degree. C. The step (c) may precede the step (b). The halide powder may be supplied to the fluidized bed furnace from outside in the form of green compact or a gas.