Comparative Study of Tribological and Mechanical Properties Between Single Layers of Al2O3 and Si3N4 Deposited on AISI 316 Stainless Steel

Al2O3 and Si3N4 coatings have been extensively studied separately, showing excellent performance in resistance to corrosion and wear. In the present work, the structural, morphological, mechanical and tribological properties of Al2O3 and Si3N4 single-layer coatings deposited on AISI 316 stainless steel substrates were studied by means of the R. F. Magnetron Sputtering technique. By X-ray diffraction (XRD) The structures of the coatings were determined, the chemical composition was studied by X-ray Photoelectron Spectroscopy (XPS). By means of Atomic Force Microscopy (AFM) the grain size and roughness were analyzed, through Scanning Electron Microscopy (SEM) the wear surfaces produced by the Pin-On-Disk and the Scratch tests were studied. By nanoindentation technique the behavior in hardness and elastic modulus was evaluated, finding better performance in the Si3N4 coating. The friction coefficient was evaluated by Pin-On-Disk tests in dry and lubricated environments. The critical load against adhesive wear was determined for Al2O3 and for Si3N4. This study develops a comparison between the mechanical and tribological properties of the mentioned coatings, proposing their possible application in components of the food and pharmaceutical industry that are subjected to phenomena where Al2O3 and Si3N4 coatings could mitigate.