Abstract
The fabrication conditions of high-density fluorapatite (Ca10(PO4)6F2: FAp) ceramic material with submicrometer sized grains were examined by two different techniques, namely pressureless firing and pulse-current pressure firing. Firstly, FAp compact was pressurelessly fired at a temperature between 1000 and 1200 °C for 10 h. The relative density and grain size of the FAp compact fired at 1200 °C achieved 92.6% and 1.8 μm, respectively. In order to enhance the relative density but restrict the grain size below 1 μm, FAp compact was pulse-current pressure fired at a temperature between 900 and 1100 °C for 10 min. The relative density and grain size of the FAp compact were 98.8% and 0.79 μm, respectively, when the temperature increased to 1100 °C. Owing to the simultaneous achievement of high density and restricted grain growth, the tensile strain of the FAp specimen pulse-current pressure fired at 1100 °C for 10 min was investigated and found to attain 70.6% at a test temperature of 1100 °C and a strain rate of 1.48 × 10-4 s-1.
