Abstract
In this study, highly elongated Al12wt.%Si alloy flakes were produced by splat quenching centrifugally atomized droplets on a moving substrate at a small angle. The dimensions of flakes obtained under various operating conditions were measured and the influences of droplet size and impingment velocity on the flake morphology were investigated. The extension factor defined by the ratio of flake length (or width) to droplet diameter was used to represent the spreadability in the corresponding direction. The results showed that both increasing droplet size and increasing impingement velocity increased the extension factor in the transverse direction but decreased it in the longitudinal direction. As a result, the length-to-width ratio was reduced together with the decreased flake thickness to give a larger aspect ratio. The aspect ratio of as-produced flakes ranged from 200 to 800. © 1994.