A novel radiographic flow visualization technique, whose development was initiated under a NSF research equipment grant, is proposed to study the buoyancy and surface tension induced convection and their interaction with phase change in model systems relevant to materials processing, including crystal growth and casting. The technique is based on the use of metallurgically compatible, neutrally buoyant tracer particles which are more radio-opaque compared to the melt. The proposed work will include further development of the radiographic tracer technique as well as studies on the convection-mediated solidification processes, including the formation of mushy zone.
