MEVVA ion implantation of TiCN coatings; structural and tribological properties

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 449; pp. 40 - 48
• Main Authors: Ward, L.P., Purushotham, K.P., Manory, R.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.06.2019
• Subjects: Characterization; Friction; Grain size; MEVVA ion implantation; Residual stress; Surface roughness; TiCN coatings; Wear; Characterization; Grain size; Friction; TiCN coatings; Wear; MEVVA ion implantation; Surface roughness; Residual stress
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2019.04.048

•Ion implantation reduced surface roughness.•Smaller grain size was observed after Nb and W implantation.•Increased friction was observed initially for all implanted samples.•Reduced stress, friction and wear accompanied Nb implantation.•Complex interactions exist between properties due to ion implantation. The application of wear resistant metal nitride coatings, typically 2–5 μm thick, is a well-established strategy, employed for prolonging service life of cutting tools, twist drills, taps, dies. Although TiN is an established coating for such applications, in recent years attention has focused on a more diverse range of metal nitride coatings. Specifically, modifications to the TiN structure through the addition of C to produce TiCN are well established for improvement in properties such as friction coefficient and wear rates. Further improvements in tribological performance are expected by modifying the surface using ion implantation. In this exploratory study, TiCN coatings were deposited onto polished AISI 316 stainless steel substrates using commercially available physical vapor deposition technology. Coated samples were ion implanted with a range of metal ions to include Mo, Nb, W, Zr and Cr using the metal vapor vacuum arc (MEVVA) technique. Ions were implanted at a constant dose of 4 × 1016 ions/cm2. The range of techniques used to characterize the implanted layers included x-ray diffraction, Rutherford backscattering, and optical and atomic force microscopy. Dry sliding friction and wear behavior of implanted coatings was assessed using pin on disc equipment. The results showed that, with some exceptions, ion implantation generally improved friction and wear; in particular, implantation with Nb reduced stress levels, grain size, surface roughness, friction and wear rates.