Corrosion behavior of SiC-hyaluronic acid-Sr doped dicalcium phosphate dihydrate composite coating in simulated body fluid

To endow suitable anti-corrosion property in simulated body fluid for biological carbon/carbon composites (CC), a composite coating consisted of SiC inner-layer and hyaluronic acid(HYA)-Sr doped dicalcium phosphate dehydrate (SD) outer-layer was fabricated on CC. The morphology, microstructure and corrosion resistance of the SiC-HYA-SD composite coating were investigated. The results showed that SiC inner-layer could provide a rough surface for the nucleation of HYA-SD outer-layer. The SiC inner-layer served as a buffer layer between CC and HYA-SD outer-layer. HYA and SD combined together to form a hybrid outer-layer after the electrodeposition process. HYA-SD could enwrap the SiC inner-layer and then form a uniform coating with villous shape. Potentiodynamic polarization results indicated that SiC-HYA-SD composite coating exhibited better corrosion resistance in simulated body fluid compared to HYA-SD coating without SiC inner-layer.