The surface tension of liquid pure aluminium and aluminium-magnesium alloy
- Cite this article as:
- Garcia-Cordovilla, C., Louis, E. & Pamies, A. J Mater Sci (1986) 21: 2787. doi:10.1007/BF00551490
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This paper discusses the results of several experiments designed to further illustrate the recent findings of the present authors according to which, if a virtually leak-fee maximum bubble pressure system is used to measure the surface tension of liquid aluminium, a surface tension around 1100 mJ m−2 is first obtained, decreasing to the oxidized value (around 865 mJ m−2) as the experiment proceeds and oxygen enters the system mainly through the capillary walls. The peculiarities and difficulties inherent to the maximum bubble pressure method are illustrated. For instance, a study of the time needed for the surface tension to decrease to the oxidized value as a function of temperature reveals the important role played by the vapour pressure in the process. This is further illustrated by considering Al-Mg alloys, as magnesium has a different heat of vaporization and a much larger vapour pressure than aluminium at the measuring temperatures. Results for the changes in density and surface tension for the oxidized and unoxidized cases induced by magnesium (up to 8 wt%) are also presented and compared to previous data.