Investigation of Electrical Contact Resistance of Ag Nanoparticles as Additives Added to PEG 300

Abstract

The electrical contact resistance (ECR) measuring techniques were applied to study the deposit film forming process in the presence of Ag nanoparticles under boundary lubricating condition (abbreviated as NA) and the tribological performance of polyethylene glycol (PEG 300) containing different concentration of Ag nanoparticles were also evaluated. ECR values between tribo-pairs lubricated with PEG 300 containing Ag nanoparticles and blank PEG 300, which was used as a comparison, were detected on a reciprocating “ball-on-disk” mode wear tester and boundary lubricating conditions can be achieved. A series of tests were performed to investigate the effect of rubbing conditions such as normal load, frequency, and surface roughness on the ECR value. SEM and XPS were used to analyze the worn surface to confirm the results of ECR. Results showed that the use of the ECR measuring techniques permits visualization and synchronous study of deposit film formation. Variations in test conditions can only slightly affect the ECR lubricated with PEG 300 containing Ag nanoparticles but affect the ECR lubricated with blank PEG 300 significantly. It is realized that the anti-wear property is related to the formation of a deposited film of Ag nanoparticles.