Abstract: This article describes a method named Powder-Compact Foaming Technique to produce close cell aluminum foams. Porous Al was fabricated by decomposing of sodium nitrate powders at initial compacted precursor. At the first Al and NaNO3 powders were mixed together and then compacted to initial precursor. At the final the precursor put in the sintering furnace. The gas released during sintering and also the mushy aluminum was the source of the produced pores. The effect of initial compacting pressure, heating temperature and weight ratio of powders have been investigated. Visual inspection and scanning electron microscopy (SEM) were utilized to characterize the porous samples. Analyzing the properties of the aluminum foams showed that the optimum weight fraction for blending initial powders was %2 wt. NaNO3. In addition, if the initial compacting pressure of the powders was decreased to below 250MPa, the foaming process did not take place properly. The optimum time and temperature of this process were 15 min at 680◦C.

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