This research aims at foaming an Al-12Si alloy by using CaCO3 powder
as a foaming agent added to the agitated melt in different weight percents.
The foaming process was carried out at different foaming temperatures of
700C˚, 750 C˚ and 800C˚ for 5, 10 and 15 minutes using different foaming
agent percents (0.5, 1, and 1.5) wt%. The metallic foam had been
characterized by microstructure examinations, density and porosity and
compression tests.
It was found from the results that there is an ability to produce metallic
foams based on Al –Si alloy by using CaCO3 as a foaming agent without the
need for adding ceramic stabilizing materials which are always added in a
high percent. The mach inability problems caused by the presence of these
materials can therefore be avoided.
It was also pointed out that the porosity of metallic foams fabricated in
this work increased as the foaming agent percent increases within the range
used (0.5% - 1.5 %) and the preferred amount is 1%, where the optimum
foaming time is 10 minutes at a foaming temperature of 750 C˚.