The precise knowledge of thermophysical properties becomes increasingly important as progress is made in numerical simulations of complex processes. With the improvement of the models, the limiting factor in predicting the real process is determined by the accuracy of the input parameters characterising the material under study. For high temperature melts, such as liquid metals, containerless methods are the best choice for their measurement. They avoid contamination of the melt, give access to the undercooled regime and allow accurate measurements of thermophysical properties sensitive to surface contamination, such as surface tension. During the MSL-1 mission (Microgravity Science Laboratory), undercooling experiments were performed using the electromagnetic levitation facility TEMPUS (Tiegelfreies Elektro Magnetisches Prozessieren Unter Schwerelosigkeit) to measure thermophysical properties and to study the nucleation and growth phenomena of selected metals and alloys. Following thermophysical properties were measured: specific heat, thermal expansion, electrical conductivity, viscosity and surface tension. The range of materials investigated included pure metals, binary alloys, and multicomponent alloys. Among the latter, special attention was given to the new easy glassforming systems and to alloys with quasicrystalline symmetry. The experiments were very succesful: large undercoolings were obtained and many melt cycles could be performed. The large amount of scientific data, consisting of digital and video signals, requires an extensive analysis, which, to some extent, is still not complete. This paper reports on the experiments and some selected results already available.
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