Interface Characterization of Plasma Sprayed Hydroxyapatite Coat on Ti 6Al 4V

Hydroxyapatite (HA), a material proven to be biocompatible within the human body, has been produced to a high level of purity. This material has been applied as a coating on Ti-6Al-4V alloy by using the air plasma spraying technique. The coat was characterizted with SEM, XRD, FTIR and Raman spectroscopy methods to consist of a mixture of calcium phosphates including HA mainly and traces of tricalcium phosphate, tetra calcium phosphate and calcium oxide phases. This HA phase was dehydrated and partially decomposed to oxyapatite and amorphous HA. EPMA method was used cross-sectionally on the interface in order to determine the depth profiles and elemental maps of Calcium, Phosphorous, Oxygen, Titanium, Vanadium and Aluminum elements. The results clearly showed the evidence of interdiffusion at the interface. Ultimately, the diffusion depth of each element was studied and compared with each other.