The effect of annealing on the properties of bovine bone was investigated over the temperature range of 400 oC to 1300 oC at a ramp rate of 10 oC/minute. The XRD results indicated that annealing at between 600 oC and 1100 oC resulted in phase pure hydroxyapatite (HA). However, decomposition of HA to form tri-calcium phosphate was observed for samples annealed above 1000 oC. Thermo-gram analysis of bovine bone revealed the existence of organic combinations that was completely removed from the structure during heat treatment above 600 oC. Annealed bovine bone between 800 oC-1000 oC exhibited features of interconnecting pore structure, suitable for biomedical application. The study revealed that proper heat treatment through the control of annealing temperature represent a viable method to produce a HA structure from bovine bone.
Keywords: Hydroxyapatite, Bovine bone, Annealing, Microstructure.