Transparent β-tricalcium phosphate ceramics prepared by spark plasma sintering

β-tricalcium phosphate (Ca3(PO4)2, β-TCP) is known to be biocompatible and osteoconductive. In the present study, β-TCP ceramics were prepared by the spark plasma sintering (SPS) technique at temperatures ranging from 800 to 1000°C at a pressure of 60 MPa for 10 min at a heating rate of 25°C/min. No phases other than β-TCP were detected in the samples sintered at 800, 900 and 1000°C by X-ray diffractometry. The relative densities of the β-TCP ceramics sintered at 800, 900 and 1000°C were 70, 95 and more than 99%, respectively. Transparent β-TCP ceramics were obtained at 1000°C for 10 min. From the results obtained by scanning probe microscopy, the ceramics prepared at 800 and 900 °C were found to have a few pores. The transparent ceramics had an average grain size of 1.5 μm and seemed to be pore-free.