METHOD AND TRANSFERRED ARC PLASMA SYSTEM FOR PRODUCTION OF FINE AND ULTRAFINE POWDERS

摘要

The present invention is concerned with a method for the production of fine and ultrafine powders of various materials such as metals, alloys, ceramics, composites etc., through a transferred arc plasma system. The method comprises vaporizing or decomposing the material in the plasma reactor, condensing the vapor in a quench tube comprising two sections, the first one for indirectly cooling or heating the vapor, and the second one for directly cooling the vapor. The powder is recovered i n a conventional collection unit. The two step condensation in the quench tube allows a substantial control of powder properties like crystallinity, size distribution and mean particle size.