Local convective flows in partly solidified alloys
Abstract
Channel formation in a dendritic mushy zone is examined with reference to experimental results obtained for an acqueous system, NH4Cl-H2O, and a low-melting metallic system, Pb-Sn. The problems of channel nucleation, propagation, and prevention are considered for a configuration in which heat flow is directed downwards and growth occurs upwards into a positive temperature gradient. It is found that channels nucleate at the growth front by double diffusive perturbations into the quiescent bulk liquid, and not by perturbations within the dendritic framework of the mushy zone.
- Publication:
-
IN: Structure and dynamics of partially solidified systems; Proceedings of the NATO Advanced Research Workshop
- Pub Date:
- 1987
- Bibcode:
- 1987sdps.proc....5H
- Keywords:
-
- Convection;
- Crystal Growth;
- Lead Alloys;
- Mushy Zones;
- Solidification;
- Two Phase Flow;
- Ammonium Chlorides;
- Aqueous Solutions;
- Dendritic Crystals;
- Microgravity Applications;
- Space Commercialization;
- Tin Alloys;
- Solid-State Physics