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Indexed by:会议论文

Date of Publication:2012-01-01

Included Journals:CPCI-S

Page Number:115-120

Key Words:Aluminum Foam; Cell structure; Solidification; Mechanical stirring; Electromagnetic stirring

Abstract:Metal foam is formed by dispersing the bubbles in the melt. The nucleation, evolution and the solidification behavior of the bubbles can be influenced by the stirring mode and the foaming parameters. In this paper, the effects of different stirring modes on Al foam foaming process were investigated during the direct melt foaming process. The stirring modes include mechanical stirring, electromagnetic stirring, and mechanical-electromagnetic combined stirring. Comparative tests were designed to determine the effective laws of stirring modes in the aluminum foaming process and fmd the right range of parameters of stirring modes. Keep the same mechanical stirring time, with the increase of mechanical stirring frequency, the porosity of Al foam will be constantly improved, the pore structure also tends to unifoitn. The stirring effects of the spiral electromagnetic field are better than the travelling wave electromagnetic field. The effects of the spiral electromagnetic-mechanical combined stirring are better than the situations of the single electromagnetic stirring or the single mechanical stirring.