Solid-State Sintering Synthesis of Biphasic Calcium Phosphate/Alumina Ceramic Composites and Their Mechanical Behaviors

In this present study, we report the fabrication of biphasic calcium phosphate (hydroxyapatite-tricalcium phosphate), abbreviated as BCP. The BCP was composited with alumina by grinding process and continuously sintering at 1200 °C for 2 hours. The sintering triggered the partial changes of crystalline phase from hydroxyapatite to tricalcium phosphate. Some fundamental characterizations were conducted to reveal the crystal structure, microstructural morphology, and mechanical strength, by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and Vickers hardness test, respectively. Our results clearly showed that the desired crystalline phases of the composites have been successfully formed. The SEM data captured compact ceramic composites of BCP/alumina. On top of that, introducing of alumina into BCP leads to enhancing the mechanical strength of the composites, having maximum Vickers hardness of nearly 0.38 GPa. Therefore, the composites meet the criteria for load-bearing application in human dentin.