Preparation of foamed magnesium alloy with dolomite as foaming agent and thickener was carried out. The effects of dolomite amount

particle size and adding temperature on structure of foamed magnesium alloy were investigated. The results reveal that dolomite can be used as foaming agent and thickener to prepare foamed magnesium alloy with uniform pore structure and high porosity. However

it has the defects of gas cavity and pore-free layer at the bottom. The minimum density of magnesium foam is 0.38 g/cm

3

and the maximum porosity is 78.7%. Dolomite is decomposed in large quantities when heated above 650 ℃

which can be used as foaming agent of magnesium foam. As thickener and foaming agent

dolomite cann’t be decomposed completely

and its residues and decomposition products are basically distributed evenly in the matrix and locally agglomerated at the edge of the hole. The density of foamed magnesium alloy is decreased with the increase of dolomite content in the range of 1%～2.5%. The density of foamed magnesium alloy is decreased at first and then increased with the increase of the size of foaming agent in range of 74～250 μm

and the turning point is 150 μm. In range of 620～710 ℃

as the temperature of dolomite increases

the density of the foamed magnesium alloy is decreased firstly and then increased. The turning point is 680 ℃. The change of porosity of foam magnesium alloy is the opposite to that of density.