Aluminum Foam Infiltration Study

Aluminium foam is a new kind of material composited of gas and Al or Al alloy, integrating high specific strength and functionalities. Because of its multi-functionalities, aluminum foam has much potential applicatious in such fields as automotive, aviation and building industry, etc.The preparing of aluminium foam by penetrating has some benefits, especially the controlling of pore ctructure. Some deficiencies are existing in tis processes, such as high cost and pollution to the environment. In order to preparing aluminium foam with open-cell, a new procession using two different metals was used in this paper. Taking lower melting point of zinc particles as the precursor, higher melting point of Al melt was filled into the precursor. This new processing has some advantages, such as low cost, precarsor metal Zn recyclable, no polluting to the environment.The optimized processing parameters were studied in this paper. The heat transfer equation was obtained through theoretical calculation. Based on this, modifing the size of zinc particles, zinc particles preheat temperature, gas pressure, aluminum melt temperature, and the die preheating temperature, then the parameters of procession were deduced.The results show that, the optimized processing parameter is that as fallowing:the preheating temperature of aluminum melt and the die 740℃, the preheat temperature of zinc particles 220℃, and the size of zinc particles 3mm and 4mm. The talcum powder was coated on the surface of zinc particles, and a layer of talcum powder was sprinkled between the interface of the zinc particles and molten aluminum, so this heat obstruct layer existing and benefiting to the penetration.The compressive propertie of aluminium foam indicated that:with the same pore size, yield strength can be decreased by increasing porosity of open-cell foam. With the pore size 3mm, yield strength was in the range of 5.2-2.4 MPa while porosity were 60-71%. With the same porosity, yield strength can be increased by increasing pore size of open-cell foam. With the porosity 63%, yield strength were 1.9 and 3.2 MPa while pore size were 3mm and 4mm. With the porosity 67%, yield strength were 1.8 and 2.7 MPa while pore size were 3mm and 4mm.The residual content analysis of Zn show that the percentage composition of zinc decreases with increasing porosity of open-cell foam. The composition of zinc is in the range of 11.3-4.5% while porosity were 60-71%.