Speaker
Description
At elevated temperatures liquid metals are chemically highly reactive. This makes the investigation of these materials and the precise measurement of their (thermophysical) properties very challenging if conventional container- or substrate-based techniques are used.
Containerless levitation techniques are therefore indispensable. They grant access to high temperatures, to the investigation of highly reactive materials (Ti, Zr, V, ..) and to the deeply undercooled range.
Depending on the application purpose and material, three main methods are currently in use: The techniques of electromagnetic levitation, electrostatic levitation and, increasingly important, aerodynamic levitation. Microgravity (µg) environment offers additional benefits. For instance, the nearly negligible positioning fields needed under µg lead to the suppression of the disturbing turbulent fluid flow which is otherwise present in electromagnetic levitation under ground-based conditions.
The present lecture will give an overview on all three levitation techniques with a focus on ground-based electromagnetic levitation. Some diagnostic means will be presented in order to determine thermophysical properties like density, surface tension, viscosity, self-diffusion coefficient, electrical and thermal conductivity, heat capacity, emissivity and others.
Some important results will be highlighted and recent trends/developments will be discussed.
| Speaker Country | Germany |
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