Tribo-electrochemical investigation of 60NiTi alloy in saline solution

• Published in: Journal of Alloys and Metallurgical Systems Vol. 6; p. 100074
• Main Authors: Okoani, Anthony Onyebuchi, Nand, Ashveen, Ramezani, Maziar
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2024; Elsevier
• Subjects: 3.5 wt% NaCl electrolyte; Corrosion-wear; NiTiNOL60 alloy; Oxidation; Three-body abrasion; Wear mechanisms; Three-body abrasion; Oxidation; Wear mechanisms; 3.5 wt% NaCl electrolyte; NiTiNOL60 alloy; Corrosion-wear
• ISSN: 2949-9178; 2949-9178
• DOI: 10.1016/j.jalmes.2024.100074

This research explores the tribocorrosion behaviour of 60NiTi alloy, also known as NiTiNOL60, when exposed to a saline environment. Our investigation focuses on understanding the relationship between corrosion and wear rates and assessing surface damage and material degradation. To conduct our experiments, we employed a linear reciprocating ball-on-plate tribometer coupled with electrochemical polarisation using a three-electrode cell configuration to assess the combined effects of corrosion and sliding wear. Surface characterisation was carried out through scanning electron microscopy and energy dispersion spectroscopy, revealing the material to be a Ni-rich 60NiTi alloy, with surface oxidation evident in the electrolyte medium. Our electrochemical findings indicate the occurrence of localised corrosion in both cathodic and anodic regimes, with corrosion pit nucleation, cavities, and cracks being accelerated by reciprocating sliding and corrosion potential. These interactions exposed the material surface to various wear mechanisms, including abrasive, adhesive, oxidative, corrosive, and fatigue processes. This study underscores the significant influence of mechanical properties on the rate of material degradation due to corrosion, while also highlighting the substantial impact of prevailing electrochemical conditions on the rate of mechanical material removal. This paper offers valuable insights for designers working on load-bearing structures in saline environments. •This study examined the behaviour of 60NiTi alloy in a saline environment.•The research integrated tribological and electrochemical analyses.•Potentiodynamic polarisation revealed localised corrosion in cathodic and anodic regions•Abrasive, adhesive, oxidative, corrosive and fatigue wear mechanisms were unveiled.•Equilibrium rate at passivation and repassivation plays a key role in tribocorrosion