Tribocorrosion studies on diamond-like carbon film deposited by PECVD on 304 stainless steel in simulated body fluid

In this paper, a diamond-like carbon (DLC) film with a controlled content of hydrogen (20%) and carbon (80%) was deposited onto a 304 stainless steel (304SS). Tribocorrosion tests were performed following immersion in simulated body fluid (SBF) solution. The DLC film with hydrogen and carbon control decreased the SS304 corrosion susceptibility 59-fold, compared to the bare surface, improving on the corrosion protection provided by DLC reported in the literature. Debris or nanoparticles from corroded metals can cause cytotoxicity or genotoxicity towards many cells, so these possible effects were evaluated using A172 glial cells (ATCC #CRL-1620 glioblastoma). The DLC film was not genotoxic or cytotoxic towards the glial cells. Furthermore, no cytotoxicity or genotoxicity was observed in the A172 cells after exposure to the SS304 covered with DLC film, even after 24 h of incubation, when compared to untreated cells. The methodology adopted, using a silicon interface between the DLC and the 304SS, was effective in preventing delamination of the DLC film. This report provides full information concerning methods for the production and characterisation of this DLC film.