Formation and wear performance of diamond-like carbon films on 316L stainless steel prepared by cathodic plasma electrolytic deposition

Abstract

Diamond-like carbon (DLC) films were deposited on a 316L stainless steel substrate by a cathodic plasma electrolytic deposition (CPED) method at 200 V with different electrode spacings in a dimethyl sulfoxide and NaCl solution. The discharge characteristics and deposition mechanism of the deposition process were studied by analysing the current-voltage (I-V) curve and the optical emission spectrum (OES) of the CPED process. The microstructure of the films was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and focused ion beam (FIB). Infrared spectroscopy measurements showed that the DLC films were hydrogenated carbon films. Raman spectrum and XPS analysis showed that the films were typical DLC films. The SEM morphology of the deposited films showed that the films were rough. The SEM image of the FIB-milled cross section showed that the average thickness of the films was approximately 200 nm. The tribological tests of coated and uncoated samples indicated that the wear-resistant performance of substrate was improved by the DLC films.