Physicochemical characterisation of tribolayers by micro-Raman and GDOES analyses

Using techniques such as scanning electron microscopy (SEM), micro-Raman spectroscopy and glow discharge optical emission spectroscopy (GDOES), this work aimed to develop a physico-chemical methodology for characterising tribolayers. Reciprocating sliding tests (DLC slides without rolling on a flat surface of AISI 304 stainless) under a special atmosphere (refrigerant R134a) were performed. The use of scanning electron microscopy made characterising the evolution of the tribolayers possible. The Raman spectroscopy results revealed the formation of an oxide tribolayer associated with the incorporation of fluorine from the atmosphere. This result was corroborated by GDOES analysis, which also provided information about the effect of the test time on the tribolayer thickness. •A physicochemical methodology for characterising tribolayers was developed.•Reciprocating sliding tests under special atmosphere were performed.•Raman spectra allowed the chemical characterisation of the tribolayer.•GDOES analysis was essential to investigate the tribolayer formation and evolution.•The association of the techniques allowed a broad characterisation of tribolayers.