Microwave synthesis of hydroxyapatite bioceramic and tribological studies of its composites with SrCO3 and ZrO2

Hydroxyapatite (HAp) powders were prepared successfully using microwave-assisted co-precipitation method. HAp powder was characterized by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy for structural confirmation of the prepared material. Further, six composites of HAp with SrCO₃ and ZrO₂ were synthesized to study the morphological and tribological behaviour. Three composites of HAp with three varying 2, 4, 6 wt% of SrCO₃ and similarly other three with ZrO₂ were prepared using solid-state route method. Scanning electron microscopy (SEM) analysis confirmed that the presence of SrCO₃ and ZrO₂ among HAp particles helps in grain growth during the sintering processes. The tribological study reveald that the inclusion of SrCO₃ and ZrO₂ in pure HAp enhanced the resistance to wear and specific wear rate. The average grain size of HAp–ZrO₂ was observed more in comparision to the average grain size of the HAp–SrCO₃. The values of the specific wear rate and wear of HAp–SrCO₃ and HAp–ZrO₂ composite ceramics lies in the range from 4.13,239 × 10⁻⁵ to 5.44517 × 10⁻⁵ mm³/Nm and 4.68693 × 10⁻⁵ to 6.10099 × 10⁻⁵ mm³/Nm, respectively.