Novel substantial reductions in sintering temperatures for preparation of transparent hydroxyapatite bioceramics under ultrahigh pressure

A novel method for preparing highly transparent hydroxyapatite bioceramics at relatively low temperatures (325-450 °C), i.e. about 60% lower compared with other commonly used preparation methods, has been developed under ultrahigh pressure (UHP; 2.0-5.0 GPa). UHP can remarkably restrain grain growth, enhance density and microhardness and we have characterized the morphology, density and mechanical properties of the prepared ceramics. We reason that these bioceramics are highly transparent due to the negligible light scattering from the nanosized grains and pores in the samples.