Monophasic Tungsten Carbide

Details Monophasic Tungsten Carbide Monophasic Tungsten Carbide

2006-09-19

2006-09-19

Langel, Wayne A. (Department: 1754)

Powder metallurgy processes

Powder metallurgy processes with heating or sintering

Metal and nonmetal in final product

C423S440000

Reexamination Certificate

active

07108831

ABSTRACT:
The present invention relates to a method of producing tungsten carbide by gas phase direct carburization of a tungsten-oxide containing starting material, wherein the starting material is reacted with a reaction gas at an increased temperature. The starting material is first heated to a first temperature greater than or equal to 600° C., before reacting with a reaction gas while increasing the temperature to a second temperature that does not exceed 850° C., wherein the reaction gas is selected from the group consisting of CO and a COH2gas mixture comprising up to 20% by volume H2.

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