Fabrication of lotus-type porous aluminum using thermal decomposition of magnesium hydroxide

Lotus-type porous aluminium was fabricated using a thermal decomposition of magnesium hydroxide in a vacuum. The effect of addition of magnesium hydroxide on the porosity and the average pore diameter were investigated. The hydrogen dissolved in molten aluminum through thermal decomposition of magnesium hydroxide when the melt solidified evolves pores. Furthermore, magnesia formed through thermal decomposition of magnesium hydroxide in the melt serves as nucleation sites for the pores. The porosity and the number of the pores increase with increasing amount of magnesium hydroxide, and the average pore diameter is not much varied with amount of magnesium hydroxide.