About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Ceramic Materials and Processing
|
| Presentation Title |
Rheology of ceramic suspensions subjected to AC electric fields for freeze-casting |
| Author(s) |
Dipankar Ghosh, Sivakumar Chithamallu |
| On-Site Speaker (Planned) |
Dipankar Ghosh |
| Abstract Scope |
Alternating current (AC) electric fields can extrinsically tune freeze-cast microstructure, originating from field-induced increase in viscosity of ceramic suspensions. However, the changes that occur in a ceramic suspension and rheological behavior, ultimately affecting freeze-cast microstructure, are not well understood. The viscosity and temperature of ceramic suspensions subjected to AC field and direct heating were measured, revealing that the increase in viscosity is due to dielectrophoretic forces rather than field-induced heating of suspension. While very high viscosity of suspensions indicated strong flocculation, in situ X-ray imaging pinpointed the field time window during which strong flocculation occurred. With the increasing field duration, freeze-cast microstructure became increasingly dendritic. For a short field duration, weak flocculation did not affect viscosity but enhanced the propensity for particle entrapment within ice crystals, resulting in dendritic freeze-cast morphology. Longer field durations resulted in a strongly flocculated state with a strong network of particles, preventing freeze-cast microstructure formation. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Ceramics, Characterization, |