Influence of zirconia on microstructure of bioactive glass coated on stainless steel for biomedical application

We investigated the effects of zirconia on microstructure and characterization of bioactive glass coating. Coatings were performed by sol-gel method and thermal properties of the prepared gel were studied by differential thermal analysis (DTA). X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) was used to investigate the microstructure and morphology of the coatings. After heat treatment in 700°C, bioglass was crystallized partly and hydroxyapatite (HA) and tetragonal zirconia formed that confirmed the bioactivity and toughness of glass-ceramic prepared by sol-gel method. Crack free and homogenous coatings were obtained. Coating without zirconia was obtained different grain size. In the case of with zirconia, the microstructures are composed of nanoplates. It seems that an activation barrier on the growing of nanoplate excites.