Influence of Tiron concentration on dispersability and sintering behaviors of hydroxyapatite in an aqueous system

Rheological and sintering behaviors of hydroxyapatite slurries with different Tiron concentrations were investigated. It was shown that HAp slurries could be stabilized at pH 11 with 2.25 wt% Tiron concentrations. Results confirmed that well dispersed slurries could be obtained with solid content as high as 50 wt%. Zeta potential measurements were conducted on HAp powders evaluated the influence of dispersant on surface charge properties of the particles. X-ray diffraction technique was used to study the crystalline phase evolution; scanning electron microscopy was used to estimate the particle size of the powder and fracture surfaces of bodies sintered at various temperatures. After sintering process at 1200 and 1350 °C, relative density and bending strength of HAp samples reached 76.67% and 92.18% and 57.77 and 97.36 MPa, respectively.