SYNTHESIS OF ULTRAFINE METAL AND ALLOY POWDERS

THE TREND IN ALL MATERIALS IS TOWARD THE CONTROL OF MICROSTRUCTURE. IN CERAMICS AND CERMETS THE EMPHASIS IS ON THE REDUCTION OF CRYSTALLITE SIZE AND THEREBY ON IMPROVING PHYSICAL PROPERTIES. POWDERS SHOULD BE EQUIZAXED AND LIMITED TO SUBMICRON RANGE, WITHIN A NARROW AND SPECIFIC SIZE DISTRIBUTION. EVEN MORE IMPORTANTLY LARGE QUANTITIES OF POWDERS MUST BE AVAILABLE AT REASONABLE COST. AS PRESENTLY PRODUCED, ULTRAFINE POWDER OF METALS ARE EITHER UNAVAILABLE OR PROHIBITIVELY EXPENSIVE. ART PROPOSES TO INVESTIGATE NEW PROCESS CONCEPTS THAT ARE EXPECTED TO YIELD ULTRAFINE POWDERS OF A VARIETY OF COMPOSITIONS. FURTHERMORE THE CONCEPTS ARE SUCH THAT THEY SHOULD BE SCALED TO PRODUCTION RATES, AND SHOULD BE ECONOMICAL. LASTLY, THEY OFFER THE POSSIBILITY OF PRODUCING ULTRAFINE POWDERS UNDER HIGHLY CONTROLLABLE CONDITIONS, AND THUS YIELD POWDERS WHOSE PROPERTIES ARE NOT ONLY CONTROLLABLE BUT ALSO REPRODUCIBLE.