Thermophysical properties of Al and Mg alloys for metal foam fabrication

The rheological characteristics are the most important factors in the metal foam manufacturing. The surface tension (by the ring method) and the viscosity (by the rotation method) of recycled Al alloys and Mg-Al alloy (AM60) have been measured under pure Ar or SF6 + CO2 atmosphere. The results show that the surface tension and the viscosity of these alloys decrease with increasing temperature together. The addition of Si, Cu and Zn to pure Al decrease the surface tension and increase the viscosity. This anomalous behavior has the relation of the preferential adsorption of high activity elements on the surface.