Wetting of pure aluminum on filter materials graphite, AlF3 and Al2O3

The wettability of pure aluminium on filter materials is believed to be an important factor affecting the filtration of aluminium. The contact angle of molten aluminium on graphite, alumina and AlF3 has been measured in 1 atmosphere of argon with an oxygen partial pressure of about 10-17 Pa in the temperature range of 1000-1800ºC. Improved techniques to remove the aluminium oxide layer from a molten aluminium drop have been employed in a horizontal graphite tube furnace. The wettability of aluminium on graphite, alumina and AlF3 has been discussed and compared with the aim to obtain “new” and more effective filter materials.