Dolomite waste recovery for producing aluminum metal foams via liquid metallurgy

Dolomite (MgCa(CO3)(2)) extraction is one of the most important mining activities. The objective of the present work is to recover solid wastes from dolomite industry and examine the potential of metal carbonates as gas generating agents in order to replace hazardous and expensive foaming agents like the group of hydrides. In order to generate powder sizes of the dolomite mineral several samples were ground using an automated mortar and sieved into various powder size grades. The dolomite powder is added to aluminum melt in order to achieve from 0.5 to 3% in a weight of dolomite content. Foaming heat treatment was carried out on aluminum melt at different times and temperatures. Foam densities lower than 0.8 g/cm(3) were obtained and the foam structure showed a low degree of aluminum draining and a good fine cell size distribution. Density and microstructure characteristics of aluminum foams using dolomite as foaming agent were compared with those obtained with titanium hydride (TiH2) as foaming agent.

Dolomite waste recovery for producing aluminum metal foams via liquid metallurgy Articles