The rate of oxidation can be further enhanced by reducing the ferrotungsten particle size to -1/4 mesh size. The size reduction may be achieved by mechanical milling or sieving to remove the larger fraction. Additionally, the rate of oxidation may also be increased by enhancing the concentration of oxygen in the calciner atmosphere. This may be accomplished by increasing the flow rate of the oxidizing gas into the calciner or by augmenting the amount of oxygen in the gas.
The following examples are provided to enable those skilled in the art to more clearly understand and practice the invention. These examples should not be considered as a limitation upon the scope of the invention, but merely as being illustrative and representative thereof.
Oxidation tests on representative ferrotungsten samples were performed in air at different temperatures in a muffle furnace. Samples of ferrotungsten were weighed and placed in previously weighed crucibles. The crucibles were then placed in a muffle furnace which had been heated to the desired temperature. The crucibles were removed at approximately 2 hours intervals, cooled, and weighed. Heating in the muffle furnace was continued until no further weight gain was observed. The data for these experiments are represented in FIG. 1.
FIG. 1 is a graphical representation of the effect of temperature on the oxidation of ferrotungsten.
Tungsten Powder Manufacturer & Supplier: Chinatungsten Online - www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn