Effect of chemical composition on fabrication of HAp-YSZ-Ti composites by spark plasma sintering method

This research examines the thermal behavior and sintering characteristics of hydroxyapatite (HAp) composites with yttria-stabilized zirconia (YSZ) and titanium via the spark plasma sintering (SPS) method. This study uses simultaneous thermal analysis (STA) to investigate the decomposition behavior of composites. During the sintering process, data on displacement, temperature, time, and current were recorded. A key challenge encountered was the fracture and crushing of the samples after the sintering process. The results show that the decomposition temperature of pure HAp (sample 100-0-0) occurs around 800 °C. In contrast, adding 4% titanium and 6% YSZ to the sample composition increases the decomposition temperature above 1000 °C. A further increase in YSZ content, up to 31%, leads to a decomposition temperature of approximately 1000 °C. These findings show that the presence of titanium and its conversion to TiO2, together with YSZ, increases the stability of the composite materials and thus reduces HAp decomposition and affects the thermal behavior of the sintered samples.