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The surface tension and density of three liquid AlTi-based alloys (AlTiV, AlTiNb, and AlTiTa) have been measured using electromagnetic levitation as a tool for containerless processing. Surface tension has been determined by the oscillating-drop method, while the density was measured using a shadowgraph technique. Both quantities were determined over a wide temperature range, including the undercooled regime. In addition, sessile-drop and pendant-drop experiments to determine the surface tension were performed in a recently built high-temperature furnace. The measured data were compared to thermodynamic calculations using phenomenological models and the Butler equation. Generally, good agreement was found.

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The knowledge of thermophysical properties of liquid Co-Si alloys is a key requirement for manufacturing of composite materials by infiltration method. Despite this need, the experimental and predicted property data of the Co-Si system are scarce and often inconsistent between the various sources. In the present work the mixing behaviour of Co-Si melts has been analyzed through the study of the concentration dependence of various thermodynamic, surface (surface tension and surface composition) and structural properties (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of the Compound Formation Model (CFM) and Quasi Chemical Approximation for regular solutions (QCA). In addition, the surface tension of the Co 22.5 Si 77.5 (in at %) eutectic alloy, that is proposed to be used as the infiltrant, has been measured by the pendant drop method at temperatures ranging from 1593 to 1773 K. The results obtained were discussed with respect to both, temperature and concentration, and subsequently compared with the model predictions and literature data.

The wetting behaviour and interfacial interactions between liquid Al and TiB 2 ceramic have been studied by the sessile drop technique in the temperature range from 700 to 1400°C. At about 800°C, liquid Al starts to wet TiB 2 and at about 1000°C it completely spreads over the ceramic. Al 3 Ti and Al 2 O 3 are found to be the main phases precipitating at the interface. Starting from 1000°C, liquid Al either fill pores or penetrates along the grain boundaries of the TiB 2 ceramic. Scanning electron microscopy analysis of the interfaces evidences that the TiB 2 grains remain intact after the aluminium melt/ceramic interaction even at 1400°C.