LAUSR

Porous aluminum phosphate (AlPO4) ceramics was fabricated from various powders synthesized at 800 °C, 900 °C, 1000 °C, and 1100 °C, respectively, using Al(OH)3 and (NH4)3PO4·3H2O as starting materials. Effects of the synthesis temperatures and CaSO4 addition on properties of the porous AlPO4 ceramics were investigated elaborately. The experimental results revealed that water absorption and open porosity of the porous AlPO4 ceramics decreased remarkably with increasing of the powder synthesis temperatures from 800 to 1100 °C and with rising of the CaSO4 addition from 0 to 15 wt%, respectively. The SEM micrographs disclosed glass phase in the porous AlPO4 ceramics decreased markedly as the powder synthesis temperatures rose from 800 to 1100 °C. It was assumed that the formation of AlPO4 owing to the reaction of Al(PO3)3 to the residual Al2O3 could lead to considerable volume expansion and thus resulted in larger water absorption and open porosity.