Apparatus for stabilization treatment of ferromagnetic metal powder

• US 5,003,919 A
• Filed: 06/09/1989
• Issued: 04/02/1991
• Est. Priority Date: 02/12/1987
• Status: Expired due to Fees

• Current Assignee: Chisso Corporation
• Original Assignee: Chisso Corporation
• Inventors: Yamamoto, Tetsushi, Nakagawa, Etsuo, Niwano, Masaru
• Primary Examiner(s): Beck, Shrive
• Application Number:
  US07/364,489
• Time in Patent Office: 662 Days
• Field of Search: 118/19, 118/20, 118/58, 118/303, 118/716, 427/242
• US Class Current: 118/716
• CPC Class Codes: B22F 1/145 Chemical treatment, e.g. passivation or decarburisation
• CPC Class Codes: C23C 8/10 Oxidising
• CPC Class Codes: G11B 5/70605 metals or alloys
• CPC Class Codes: H01F 1/061 with a protective layer

Abstract

An apparatus for stabilizing treatment of ferromagnetic metal powder which apparatus makes it possible to form a surface-oxidized film on the powder which is as uniform and dense as possible and to afford ferromagnetic metal powder having a good quality, and which apparatus is characterized by comprising a horizontal, cylindrical, rotating type body of reactor; a feeding port for the ferromagnetic metal powder into the body; a withdrawing port for the ferromagnetic metal powder from the body; a blowing passageway for an oxidizing gas into the body; and a withdrawing passageway for the oxidizing gas from the body.

Claims

1. An apparatus for stabilizing treatment of ferromagnetic metal powder, which apparatus comprises:

a horizontal, cylindrical, rotating type reactor body provided with end walls substantially perpendicular to a cylindrical side wall which forms an inner wall of said reactor body;

a jacket for a heat transfer medium;

a port including a valve for feeding said ferromagnetic metal powder into said reactor body;

a port for withdrawing said ferromagnetic metal powder from said reactor body, which port may be used in common with said feeding port;

a passageway for blowing an oxidizing gas into said reactor body comprising an oxidizing gas inlet in communication with a pipe arranged within said reactor body coaxially with respect to the axis of rotation of said reactor body, said passageway arranged to be in substantial non-contacting relationship with ferromagnetic metal powder and said pipe, having an outlet end, extends longitudinally through said reactor body, said outlet end positioned proximate the side wall remote from said oxidizing gas inlet;

a passageway for withdrawing said oxidizing gas from said reactor body comprising an oxidizing gas outlet in communication with a duct connected to said reactor body and arranged coaxially with respect to the axis of rotation of said reactor body, said passageway arranged to be in substantial non-contacting relationship with ferromagnetic metal powder; and

a plurality of scraping up plates for said ferromagnetic metal powder arranged on said inner wall of said reactor body parallel to the axis of rotation of said reactor body and extending longitudinally from one end of the reactor body to the other end thereof.

2. An apparatus according to calim 1 wherein said plurality of scraping-up plates comprises two scraping-up plates.

3. An apparatus for stabilizing treatment of ferromagnetic metal powder, which apparatus comprises:

a horizontal, cylindrical, rotating type reactor body provided with end walls substantially perpendicular to a cylindrical side wall which forms an inner wall of said reactor body;

a jacket for a heat transfer medium;

a port including a valve for feeding said ferromagnetic metal powder into said reactor body;

a port for withdrawing said ferromagnetic metal powder from said reactor body, which port may be used in common with said feeding port;

a passageway for blowing an oxidizing gas into said reactor body comprising an oxidizing gas inlet in communication with a duct connected to said reactor body and arranged coaxially with respect to the axis of rotation of said reactor body, said passageway arranged to be in substantial non-contacting relationship with ferromagnetic metal powder;

a passageway for withdrawing said oxidizing gas from said reactor body comprising an oxidizing gas outlet in communication with a pipe arranged within said reactor body coaxially with respect to the axis of rotation of said reactor body, said passageway arranged to be in substantial non-contacting relationship with ferromagnetic metal powder and said pipe, having an inlet end, extends longitudinally through said reactor body, said inlet end positioned proximate the side wall remote from said oxidizing gas outlet; and

a plurality of scraping up plates for said feromagnetic metal powder arranged on said inner wall of said reactor body parallel to the axis of rotation of said reactor body and extending longitudinally from one end of the reactor body to the other end thereof.

4. An apparatus according to claim 3 wherein said plurality of scraping-up plates comprises two scraping-up plates.