Control of Fine Powder Production and Melt Flow Rate Using Gas Dynamics

摘要

Understanding the relationships between melt flow rates, gas-only aspiration of the atomizer nozzle and operating pressures, is crucial in the production of fine metal powder. The ability to control these gas atomization variables is elusive and most often these parameters are interdependent. In general, fine particle production and high melt flow rate have been commonly associated with operating atomizing nozzles at deep aspiration characteristics. Deep aspirations, as a result of wake-closure, have been commonly associated with robust atomization enhanced by the increase in melt flow rate. But such assumptions have not been filly explained using metal melt atomization. The investigation of these atomization variables is performed using an industrial gas atomizer nozzle and a 50 lb (22.7 kg charge weight) laboratory gas atomizer system. A pulsatile atomization model is presented to bridge the relationship between gas-only aspiration and the resulting yield from melt atomization.