Fabrication and Characterization of Sol- Gel Derived Bioactive Glass/Zirconia Composite Coating for Biocompatibility Improvement of AISI 316L Stainless Steel

The aim of this research was fabrication and characterization of bioactive glass/zirconia composite coating via the sol-gel method for corrosion behavior improvement of metallic substrate. Coating was produced on AISI 316L stainless steel (SS) substrate by spin-coating technique. Structural characterization techniques including XRD، SEM and EDS were used to investigate the microstructure، morphology and the chemical composition of the coating. The hardness of coating was evaluated using knoop microhardness test method. Electrochemical potentiodynamic polarization tests were performed in two different types of physiological solutions at 37 ºC in order to determine and compare the corrosion behavior of the coated and uncoated SS specimens. Crack-free and homogeneous bioactive glass/zirconia composite coatings were obtained without major defects. The composite coating also improved corrosion resistance of the AISI 316L SS substrates as the corrosion current density of coated samples in comparison with pristine samples was decreased. It was concluded that the sol-gel bioactive glass/zirconia composite coating can be used for improvement of corrosion behavior and thus biocompatibility of the 316L SS substrates