SPHERICAL POWDER AND ITS PREPARATION

摘要

A spherical tungsten carbide powder is characterized by that the material has a microhardness higher than 3600 kgf/mm2, and that the powder has an apparent density from 9.80 to 11.56 g/cm3. A method for the manufacture of a powder comprises the steps: a) providing a chamber comprising a rotatable crucible, b) adding material into said rotatable crucible, c) melting the material using a plasma arc discharge, d) rotating the crucible to atomize the molten material to form liquid droplets, with subsequent cooling of the droplets to obtain a powder, wherein the material added into said rotatable crucible is heated to a temperature above 40% of the melting temperature of the material before it enters the crucible. It is possible to reduce the current required for melting the stock. Heat losses are decreased, and the spherical powder obtained during atomization becomes more homogeneous in its composition and structure. The cost is reduced.