A METHOD FOR PERFORMING THERMAL REACTIONS BETWEEN REACTANTS AND A FURNACE FOR SAME

摘要

The present invention relates to thermal reactions performed at rapid transient temperatures, and a furnace (1) able to perform such reactions. The method and the furnace may suitably be applied to perform reactions between reactants where significant losses normally occur at certain transient temperatures or temperature ranges. One practical application of the present invention relates to a carbothermic method for producing Refractory Hard Metal powders, such as borides, nitrides and carbides, and a furnace designed for the performance of the method. In accordance with this method Refractory Hard Metal powders, such as boride powders can be produced with reduced loss of reactants such as C and B2O3. This can be achieved by rapid heating of the mixture containing the reactants in a critical temperature range. For the performance of this particular embodiment a two-step furnace has been applied, where the temperature in each individual temperature zone (37, 38) is respectively below and above critical temperatures of the reaction. In accordance with one embodiment of the present invention high purified boride, carbide and nitride powders with a fine grain size can be produced in a simple and cost effective manner.