PARTICLE-SIZE MEASUREMENT OF INERT-GAS-ATOMIZED POWDER

Metal powder produced by supersonic inert gas metal atomization (SiGMA) has been analyzed using several diagnostic methods. This analysis has brought to our attention several interesting and unexpected results. Some of these unexpected results concern the reliability of the various particle-measuring techniques, the procedure for proper (reproducible) particle size analysis, and the graphical representation of the data that best shows the powder's characteristics. This study has also shown that gas-atomized powders produced in the SiGMA facility have distinct size distribution characteristics that do not follow the log-normal pattern. The fragmentation mechanisms leading to droplet formation which explain the SiGMA powder size distribution data are examined. We conclude that these new powder analysis procedures are applicable to all inert-gas-atomized powder and can lead to a better understanding of an atomizing system's operative liquid disruption mechanisms. © 1990.