摘要 |
Nanograined tungsten carbide particles are formed by a controlled, simultaneous reduction carburization reaction wherein the kinetics of the carburization and reduction reactions are controlled to permit simultaneous reduction and carburization. The kinetics are controlled by reacting a reduction carburization gas mixture, preferably hydrogen and carbon monoxide by slowly increasing the reaction temperature by controlling the rate of temperature increase. Preferably, the reaction temperature will be increased less than 25 DEG C. per minute, preferably about 1-2 degrees per minute, which prevents the formation of stable, undesirable species such as W2C, which in turn interferes with the reaction efficiency.
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