51. In situ synthesis of osteoconductive biphasic ceramic coatings on Ti6Al4V substrate by laser-microwave hybridization
- Author
-
Man-Tik Choy, Ling Chen, Wing Cheung Law, Gary Chi-Pong Tsui, Ka-Wai Yeung, and Chak Yin Tang
- Subjects
Laser ablation ,Materials science ,Simulated body fluid ,Titanium alloy ,030206 dentistry ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,engineering.material ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Apatite ,Surfaces, Coatings and Films ,03 medical and health sciences ,0302 clinical medicine ,Coating ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,engineering ,Surface modification ,Ceramic ,Composite material ,0210 nano-technology ,Micropatterning - Abstract
Microwave heating is an efficient alternative approach for synthetic chemistry with many distinctive advantages of high heating rate, selective and homogeneous heating. In this study, a new laser-microwave hybridization method, which comprises laser micropatterning, microwave heating and in situ synthesis has been developed to produce titania/hydroxyapatite/tricalcium phosphate (TiO 2 /HA/TCP) composite coating on titanium alloy (Ti6Al4V) substrate. The composite coating with a fine porous network microarchitecture was selectively produced on the Ti6Al4V surface by laser ablation and alkaline treatment. Using TiO 2 sol-gel and mixed powders of calcium carbonate (CaCO 3 ) and dicalcium phosphate dihydrate (CaHPO 4 ·2H 2 O), the composite coating synthesized at a temperature of 800 °C in a short time of 20 min exhibited homogeneous microstructure, strong hydrophilicity and good adhesion strength of 34 MPa. The in vitro apatite-forming capability of the coating was examined by immersing the coated Ti6Al4V specimen into a simulated body fluid (SBF) for up to 7 days. Biodissolution was observed in the early stage of incubation, followed by apatite precipitation. The quantity and size of the apatite globules increased over time. After 7 days of immersion, the coating surface was nearly covered by a layer of bone-like apatite, showing a significant improvement of its osteoconductive property over the uncoated sample. The laser-microwave hybridization provides an efficient route to synthesize HA/TCP based coatings for bioactivity enhancement, and serves as an effective sterilization tool for implant materials.
- Published
- 2017