Development and optimisation of hydroxyapatite-ß-TCP functionally gradated biomaterial.

Use of hydroxyapatite (HAP) for biomaterials is widely established, often in a combination with titanium alloy substrates in orthopaedic and other implants. Porous HAP-based coatings undergo sintering and heat treatment processes to achieve proper level of density yet avoiding undesirable reactions and phase changes. Thermal expansion mismatch between constituents may also lead to cracking of the coating due to excessive thermal stresses.