Formation of apatite/titanium composite coatings on titanium alloy substrate using RF plasma-spraying process

摘要

To improve hydroxapatite (HA) coatings on the titanium substrate, HA/Ti composite was formed on substrates using Radio-frequency (RF) plasma spraying process, as this composite layer may reduce the residual stress due to the large difference in the liner thermal expansion coefficient between th4e substrate and HA. HA/Ti composite was prepared by controlled feeding of HA and Ti powder, as the composition of coatings becomes HA-rich toward the outmost. Coating layer was evaluated by SEM-EDX, XRD and tensile testing. Orientation in c-axis direction of prepared coatings was observed from X-ray diffraction patterns. HA/Ti composite coating gave a higher adhesive (tensile) strength over 10 MPa than direct HA coatings on substrate.