Sintering Behavior and Property of Bioglass Modified HA-Al2O3 Composite

The bioglass modified HA-Al2O3 composites were successfully fabricated by mixing HA, synthesized by wet chemical method between precursor materials H3PO4 and Ca(OH)(2), with 25wt% Al2O3 and different content of bioglass (5%, 25%, 45%, 65wt%) respectively, with a mole fraction of 53.9%SiO2, 22.6%Na2O, 21.8%CaO, and 1.7wt%P2O5, sintered in air at various temperatures (750-950 degrees C) for 2h. when the content of bioglass is below 45wt% in the composite, HA decomposes completely and transforms to beta-TCP. The main phase in this case are beta-TCP, Al2O3 and Ca-3(AlO3)(2). When the content of bioglass is above 45wt% in the composite, the decomposition of HA to beta-TCP is suppressed and the main phases in this case are Al2O3 and HA, DCP square CaHPO4 square and beta-TCP, which almost have the same chemical composition, forming ternary-glass phase, and have better bioactive than pure HA. It can also be found that at the certain addition of bioglass, the higher sintered temperature, the bigger volume density and flexural strength of the composite are, but when the sintered temperature reaches 950 degrees C, they decrease. This modified HA-Al2O3 composites by calcium silicate glass have a much lower sintering temperature and decrease the production cost much.