Abstract
Carbonitride (CNx) coatings have existed for several decades but are not well understood. Related studies have indicated that CNx coatings exhibit behaviors comparable to diamond-like carbon (DLC) coatings. Metal-doped CNx coatings are expected to show superior performance to single CNx coatings. In this study, a CNx coating and a group of CNx coatings with 6 at. % metal doping (W, Ti, Zr, or Cr) were prepared on biograde AISI 316L stainless steel (SS316L) substrates, and they were then characterized and studied for antibacterial and wear performance. The microstructure, constituent phase, nanohardness, adhesion, surface roughness, and contact angle were evaluated. The antimicrobial test used Staphylococcus aureus and followed the Japanese Industrial Standard JIS Z 2801:2010. Finally, the wear behavior was assessed. The results showed that the CNx coating was a composite of amorphous CNx and amorphous C structures. The metal doping caused crystalline metal carbides/nitrides to form in the CNx coatings, which weakened their overall integrity. All the coatings showed antimicrobial ability for the SS316L samples. The CNx-Zr coating, the surface of which had the highest hydrophilicity, produced the best antibacterial performance. However, the CNx-Zr coating showed lower wear resistance than the CNx-W and CNx-Ti coatings. The CNx-Ti coating with a highly hydrophilic surface exhibited the lowest antibacterial ability.
Highlights
Considering a coating with antibacterial ability, the first candidate would be Ag-containing coating since Ag is a well-known antibacterial element
The results showed that the CNx coating was a composite of amorphous CNx and amorphous C structures
285.9 eV, which could be deconvoluted into two components with the broader peak corresponding to (C, N) bonding and the other peak corresponding to amorphous C-Zr0.55–0.60 (a-C)
Summary
Considering a coating with antibacterial ability, the first candidate would be Ag-containing coating since Ag is a well-known antibacterial element. Over the past 30 years, a few studies have been performed on CNx. Some results indicated that CNx coatings exhibited low friction, high adhesion, and high wear and corrosion resistance. Found that among evaluated samples, a CNx coating showed the highest hardness under deposition conditions with a N/Ar ratio of 0.2 [14]. The CNx coatings, under deposition conditions with N/Ar ratios of 0.25–0.50, possessed the highest content of sp bonding and exhibited the highest wear resistance of their samples. Lai et al [22] grew a series of CNx/amorphous C-Zr0.55–0.60 (a-C) coatings on biograde Ti samples They found that the coatings showed high biocompatibility and good antibacterial performance when the C content was higher than 12.7 at. Ospina et al [31] evaluated the mechanical properties and wear performance of W-doped CNx (CNx-W) coatings prepared using the pulse arc deposition method. This study was a trial of growing CNx and metal-doped CNx coatings on SS316L steel; their characteristics and possible applications against bacteria and against wear were investigated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
