Abstract
The influence of precursor structure on the shape change and the pore formation in Al-7%Si foam is examined with the aim at establishing a graded foaming process. Metal powder layers mixed with different amounts of the foaming agent TiH_2 as well as SiC powder, which may change the viscosity, are compacted into cylindrical precursors and heated up with a mold in a furnace. It is confirmed that the pore distribution in the foam may be controlled by changing the expansion force and the viscosity locally in proper layer arrangement.
