Comparative Study on TiH_2 and CaCO_3 for Fabrication of Mg Alloy Foams

摘要

Aluminum alloy foams, new materials belonging to a special class of porous materials, have been prepared using melt foaming method. Silicon was chosen alloying element due to its low density, high strength, effective casting and reduced shrinkage. Melt foaming method is cost-effective method to fabricate metal foam. Usually, TiH_2 is applied to blowing agent, but its cost is high. CaCO_3 is one of candidates to substitute TiH_2 in the economic view-point. For the comparison of formability, Mg alloy foams were prepared by TiH_2 and CaCO_3. However, the decomposition temperature of CaCO_3 is higher than that of TiH_2. This paper will be discussed on the possible usage of CaCO_3 in the Al melt.