Surface modification of biomedical AISI 316L stainless steel with zirconium carbonitride coatings

Abstract In the paper, by using radio frequency (rf) magnetron sputtering method, a zirconium carbonitride coating was produced on AISI 316L austenitic stainless steel. The influence of substrate temperature ( T s ) on microstructure, mechanical properties, corrosion resistance and hemocompatibility were then investigated. XRD and TEM results revealed that the zirconium carbonitride coatings were almost amorphous when T s was below 400°C, while nanostructured Zr 2 CN was formed at T s of 400 °C. The nanocrystalline formation resulted in a significant increase in the nanohardness of zirconium carbonitride coatings from 17 GPa to over 32 GPa. Electrochemical testing showed that the stable zirconium carbonitride coating had improved the corrosion resistance of AISI 316L stainless steel substrate material. The characterization of platelet adhesion indicated that the zirconium carbonitride coatings presented better hemocompatibility when T s varied from 25 °C to more than 200 °C, which may be due to the lower surface roughness, interfacial tension and the rate γ s d / γ s p , where γ s d and γ s p are the disperse component and polar component of the surface, respectively.