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. 15, 2002
Filed:
Jun. 12, 2000
Philippe Tailhades, Saint-Orens-de-Gameville, FR;
Valérie Carles, Pinsaguel, FR;
Abel Rousset, Ramonville St Agne, FR;
Other;
Abstract
The invention relates to a method of preparing metal powder comprising: preparing a simple or mixed oxalate of one or more metals formed of particles with needle-like morphology having a mean acicularity ratio (length/diameter) of from 4 to 20, and a length of from 5 to 10 microns and converting said oxalate to metal or metal alloy powder by reducing treatment with gaseous hydrogen. The conversion of said oxalate can be carried out by decomposing said oxalate, in air, to an oxide and then reducing said oxide to metal or metal alloy. The metal is chosen from among the rare earth metals and the transition metals, preferably from among iron, cobalt, and nickel. The method is particularly suitable for making iron powder metal having a spongy and filament-like microstructure which makes it suitable for use in heating composition for thermo-piles. In addition, the invention relates to metal compacts unstoved or annealed which are obtained by applying compaction pressure to the powders according to the invention.