Protection and functionalization of AISI 316 L stainless steel for orthopedic implants: hybrid coating and sol gel glasses by spray to promote bioactivity

Abstract

This work presents the synthesis and deposition of hybrid sol-gel coating applied on AISI 316Lstainless steel by dipping with the aim of providing corrosion protection to the substrate. On the top of this coating a potentially bioactive glass (58S) made also by sol gel method with tetraethoxysilane (TEOS), triethyl phosphate (TEP) and calcium nitrate as precursors, was applied by spray technique. This method allows the creation of a wide distribution of particles sizes on the target. Coatings were characterized by profilometry and optical and electronic microscopy. The surface integrity and corrosion resistance of the coatings in time is analyzed by electrochemical tests in simulated body fluid (SBF).It is observed some kind of detrimental effect regarding the corrosion behavior between the bioactive dots and the underneath coating. Nevertheless the entire system results promising for further investigation since the addition of 58S bioactive particles by spray method results appealing as it is a simple way to generate bioactive points on the implant surface.