Foaming mechanism of aluminum-ash-based ceramic pellets under various sintering conditions

Abstract

Abstract Secondary aluminum dross (SAD) is hazardous waste. Because generation N2 during oxidation reaction of aluminum Nitride (AlN) from SAD, it can be used as forming agent in preparing ceramic pellets. The foaming mechanism of ceramic pellet using SAD was studied. Higher temperature can reduce total amount of pores in sample. When the particle size increased from 0.5 to 2.0 cm, the porosity first decreased and subsequently increased. The porosity was the highest (Si-Al ratio was 1 and the sintering time reached 30 min). The glass network polymerization degree in ceramic pellets decreased at 1250℃ and increased at 1260℃. The polymerization degree increased at a particle size of 1.0 and decreased at 1.5 cm. The change in the degree of polymerization of the glass network affected the liquid-phase region of the melt process. The crystalline products after sintering changed the structural denseness and strength of the pellets considerably.