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Investigation of the important parameters in a gas sparging technique for production of tungsten carbide.

Authors
Kazonich-G; Raddatz-AE; Carnahan-TG
Source
Metal Powder Rep 1988 Dec; 43(12):800-810
Link
NIOSHTIC No.
10006581
Abstract
The Bureau of Mines conducted a study to delineate the important parameters in a three-step process to produce commercial-quality tungsten carbide (wc) directly from tungsten minerals. In the process, tungsten concentrates of wolframite or wolframite and scheelite are decomposed at 1,050 deg. C in a molten mixture of nacl and na2sio3 that forms two immiscible phases. Tungsten, as sodium tungstate, reports to the halide phase and is separated from the gangue constituents, which report to the silicate phase. After decanting to separate the two phases, natural gas is sparged into the molten halide phase at 1,070 deg. C. Submicrometer crystals of tungsten carbide are initially produced. These crystals grow into thin, triangular-shaped plates up to 100 um on a side or into popcorn-shaped conglomerates.
Publication Date
19881201
Document Type
OP; Journal Article
Fiscal Year
1989
Identifying No.
OP 28-89
Issue of Publication
12
ISSN
0026-0657
NIOSH Division
RERC
Source Name
Metal Powder Report
State
NV
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division