Plasma-sprayed diopside coatings for biomedical applications

Diopside coatings have been sprayed onto Ti-6Al-4V substrates using an atmospheric plasma spray system. The phase composition and microstructure of the powders and coatings were examined by scanning electron microscopy and X-ray diffraction. The thermal expansion coefficient of diopside coating was measured by a dilatometer in the temperature range of 20-600 degreesC, which adapted to that of titanium alloy. The bond strength of coating was approximately 32.5 MPa, which is higher than that of plasma sprayed HA coating on titanium alloys substrates. The density, porosity, roughness and Young's moduli of diopside coatings were also measured. The bioactivity of diopside coating was evaluated in vitro by soaking it in simulated body fluid. After 15 days soaking in simulated body fluid, an apatite layer was formed on the surface of the coating. The results are obtained indicated that plasma sprayed diopside coating and may be a candidate for bone and dental implant. (C) 2004 Elsevier B.V. All rights reserved.