Patent Number: 6,165,412

Title: Method of making non-sag tungsten wire for electric lamps

Abstract: A method of making a potassium-doped tungsten powder is described comprising forming a mixture of ammonium paratungstate or ammonium metatungstate and a potassium-containing compound selected from a thermally unstable potassium-containing salt or a potassium tungstate, and reducing the mixture in a single step without adding additional dopants to form a potassium-doped tungsten powder. The potassium-doped tungsten powder produced by the method of this invention can be pressed, sintered and drawn to produce a non-sag tungsten wire.

Inventors: Lunk; Hans-Joachim (Towanda, PA), Salmen; Michael (Brandenburg, DE), Stevens; Henry J. (Athens, PA)

Assignee: Osram Sylvania Inc.

International Classification: C22B 34/00 (20060101); C22B 34/36 (20060101); C22B 5/00 (20060101); C22B 5/12 (20060101); C22C 1/04 (20060101); H01K 1/00 (20060101); H01K 3/00 (20060101); H01K 1/10 (20060101); H01K 3/02 (20060101); B22F 001/02 ()

Expiration Date: 12/26/2013