Preparation of aluminum foam using novel foaming agent

The thermal decomposition behavior of a novel foaming agent substituting for TiH_2 and ZrH_2 during the preparation process of aluminum foam was investigated. The effects of the foaming agent content and foaming temperature on the porosity of aluminum foam were also discussed. The experimental results show that the novel foaming agent has a wide decomposition temperature range and a slow decomposed rate; the extra viscosifier such as Ca is unnecessary while using this foaming agent; the porosity firstly increases and then decreases with foaming temperature rising; the free-bubble layer in material decreases with foaming agent addition increasing, and the free-bubble layer disappears while foaming agent addtion is more than 1.4%; an aluminum foam product characterized by no free-bubble layer, uniform bubble distribution, pore sizes of 2-5mm and porosity of 60%-80% can be obtained under the conditions the foaming temperature 740℃, foaming agent addition 1.40%- 2.20%, stirring time 3min and foaming time 5min.