Comparative Study of Microstructures and Material Properties in the Vacuum and Spark Plasma Sintered Ti-Calcium Phosphate Composites

Abstract

Sintering of Ti-biphasic calcium phosphate (BCP) is difficult because of the chemical instability of the phases at high temperature. When the sintering temperature is above 1273 K, Ti reacts with BCP and forms CaO, TiO₂, CaTiO₃, TiP etc. Conventional vacuum sintering is common for Ti powder but for Ti-BCP composites, spark plasma sintering in an inert atmosphere is a quick method to overcome the issues associated with a prolonged reaction time. In this study, the effect of two different sintering processes on the sintering reactions and mechanical and biological properties of Ti-30 vol%BCP composites were investigated and compared. Detailed micro-structural and morphological analyses were conducted using scanning electron microscopy (SEM). Mechanical properties were characterized by relative density, Vickers hardness and compressive strength measurement. Phase characteristics were analyzed by X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). Cell viability and biocompatibility were investigated using the MTT assay and by examining cell morphology. In this study, the mechanical properties and biocompatibility for both, spark plasma sintered Ti-Ca-P composites were excellent compare to vacuum sintered composites.