Electrical contact resistance and tribological behaviors of self-lubricated dielectric coating under different conditions

• Published in: Tribology international Vol. 143; p. 106086
• Main Authors: Echeverrigaray, F.G., de Mello, S.R.S., Leidens, L.M., Boeira, C.D., Michels, A.F., Braceras, I., Figueroa, C.A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-03-2020; Elsevier BV
• Subjects: Bearing steels; Coefficient of friction; Contact resistance; Dielectric properties; Dissipated energy; Electric contacts; Electrical contact resistance; Electrical resistance; Electro-tribology; Friction resistance; Lubrication; Mathematical analysis; Microslip; Self lubrication; Tool wear; Tribology; Wear sensing; AISI; HMDSO; Electrical contact resistance; HV; SHC; Dissipated energy; ECR; ASTM; EDS; RH; Electro-tribology; SEM; COF; PECVD; Wear sensing; OM; DC
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2019.106086

In this study, the electro-tribological performance of hydrogenated amorphous carbon coatings against bearing steel in different experimental conditions was continuously monitored by means of coefficient of friction (CoF) and electrical contact resistance (ECR). The influence of tribosystem variables such as humidity, velocity and lifetime on frictional and electrical response were also compared with specific wear energy calculation method. The main findings of both tribological and electrical behaviors include the dissipated energy and the micro-slip dielectric failures that can be linked to the properties of self-lubricating layers, which depend also on the working media. In this framework, the electro-tribological evaluation provides an electrical monitoring tool for coating premature wear detection in real time.
•Local recognition of micro-slip dielectric failures in real time using ECR displacement traces.•Energy transfer can gradually cause transitions on film surfaces and frictional oscillations.•High speed under 80% RH results in CoF increase, water molecule cover-break and dielectric character preservation.•Lowest specific wear energy among surface tribopairs in high speed compared to low speed at dry conditions.•Surface integrity response linked to the effects of eletrotribological system inputs, outputs and losses.