About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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Materials Research in Reduced Gravity
|
Presentation Title |
Thermophysical Properties of SiGe Melts Measured on Board the ISS |
Author(s) |
Yuansu Luo, Bernd Damaschke, Georg Lohöfer , Konrad Samwer |
On-Site Speaker (Planned) |
Yuansu Luo |
Abstract Scope |
Processing semiconductors based on EML is a challenge due to their poor electrical conductivity. In framework of the ESA project, first attempts with highly doped Si1-xGex were made on ISS. Initial results indicate that the samples could be melted, overheated by ~350°C and cooled down in 350mbar Ar. A large undercooling of ~240°C was observed thereby, followed with a quasi-homogenous nucleation. During cooling high-resolution videos were taken and digitalized to evaluate the density and thermal expansion. The surface tension and viscosity were measured by the oscillating drop technique and the electrical conductivity by a special sample coupling electronics. We found a nonlinear thermal expansion suggesting a many-body effect in the liquid beyond the regular pair potential and a strongly enhanced viscosity likely due to the internal turbulence flow.
We acknowledge the access to the ISS-EML, undertaking of the ESA & DLR Space Administration, and the financial support of BMWi50WM1750. |
Proceedings Inclusion? |
Planned: Publication Outside of TMS |