Influence of Magnesium Content on Preparation of Aluminum Foam

Abstract

Aluminum foam was prepared by foaming in melt route. Bubble growth and structure of the obtained foam blocks were investigated. Viscosity and surface tension of aluminum melt were also analyzed after adding Mg into it. The main results are as follows: expanding velocity of aluminum melt is accelerated after adding Mg and height of the foamed block is higher than that without adding Mg. The apparent density of aluminum foam increases first and then declines with increasing the Mg content. Intermetallic compounds existing in aluminum melt are largely oxidized when Mg is put into the melt and amount of the composite oxides increases obviously. These changes result in elevation of viscosity and reduction of surface tension in the aluminum melt.