Structural and bio-mineralization features of alumina zirconia composite influenced by the combined Ca2+ and PO43- additions.

ABSTRACT

The structural and bioactivity features of alumina zirconia composite (AZC) due to Ca2+ and PO43- additions are demonstrated. An in situ synthetic approach, starting from the solution precursors is devised for the powder synthesis in which the assorted range of Ca2+ and PO43- additions were done to the equimolar concentrations of Al3+ and Zr4+ precursors. The results witnessed the unique crystallization of tetragonal zirconia (t-ZrO2) at 1100 °C while Ca2+, PO43- and Al2O3 remained in their amorphous state in the system. On further heat treatment, α-Al2O3 crystallized at 1200 °C, which enforced t- → m-ZrO2 transformation while Ca2+ and PO43- still retained their amorphous state. The immersion tests in simulated body fluid (SBF) solution validated the enhanced bio-mineralization activity of AZC due to Ca2+ and PO43- additions. The results from the indentation tests demonstrated good uniformity in the elastic modulus and hardness data of the investigated specimens. Further, in vitro cell culture tests ascertained the bioactivity of all the AZC compositions.