Electromagnetic enhancement of wetting in the Al-Al{sub 2}O{sub 3} and Al-graphite systems

Conference · Fri Dec 31 04:00:00 EST 1993

OSTI ID:143656

Bunyan, P J; Huo, S H ^[1]

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1. Univ. of Melbourne, Parkville, Victoria (Australia). Dept. of Mechanical and Manufacturing Engineering

The effect of a pulsed electromagnetic field on wetting in the Al-Al{sub 2}O{sub 3} and Al-graphite systems has been investigated in this study. In the sessile drop test the applied electromagnetic field can cause strong circulating surface flow and oscillation of the aluminum droplet. At temperatures above 800{degree}C the oxide film breaks up and fragments can be seen to move over the surface of the droplet under the action of the induced electromagnetic stirring. A rapid decrease of contact angle was observed to occur when surface oscillation occurred. The rate of decrease of the contact angle has been found to be related to the intensity of the oscillation induced by the field. The amplitude of the resonant oscillation is a function of the pulse frequency and amplitude. The treatment temperature and oxygen partial pressure can also influence the strength of oscillation and therefore the rate of decrease of the contact angle. The measured data provide an insight into the influence of the electromagnetic field on wetting. Within 15 minutes the use of the field can reduce the contact angle by 25{degree} and 22{degree} respectively for the Al-graphite and the Al-Al{sub 2}O{sub 3} systems at 800{degree}C.

• OSTI ID: 143656
• Report Number(s): CONF-930246--; ISBN 0-87339-251-5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
ALUMINIUM OXIDES
COMPOSITE MATERIALS
GRAPHITE
PHYSICAL RADIATION EFFECTS
WETTABILITY