Sintering effects of mullite-doping on mechanical properties of bovine hydroxyapatite

•Above 1000 °C, decomposition of HA and new phase formations occur in HA doped with powder mullite.•Whitlockite and gehlenite play an important role in mechanical improvement up to 10 wt% mullite reinforcement.

In this study, sintering effects on microstructural behavior of bovine derived hydroxyapatite doped with powder mullite are considered in the temperature range between 1000 °C and 1300 °C. Results show that maximum values of both compressive strength and microhardness are achieved in the samples sintered at 1200 °C for all mullite additions of 5, 7.5, 10 and 12.5 wt%. Moreover, above 1000 °C, decomposition of HA and new phase formations such as whitlockite and gehlenite play a major role in both compressive strength and microhardness properties which increase up to 10 wt% mullite reinforcement.