Self-repairing and tribological behaviour of steel–steel friction pairs lubricated with an oil with magnesium silicate hydrosilicate as additive

Abstract

Magnesium silicate hydrosilicate (MSH) was added into a lubricating oil as an additive for testing self-repairing capability of a friction pair when it is lubricated. A systemic examination of the structure and chemical composition of the surfaces with self-repairing layers was carried out with an expectation of reducing the wear and even fully repairing the surfaces through the newly grown layers. The wear behaviour of the surfaces, including that having the deposited self-repairing layers, was examined with reference to the lubricated steel friction pairs, being loaded under different working conditions. The treated surfaces and their chemical composition were examined using scanning electron microscopy (SEM) and EDS/XRD, respectively. The results showed that the level of the concentration of the additive in the lubricating oil does not affect the chemical composition of the self-repairing layer formed, and lubricating oil with 1.0% MSH is an optimal concentration value for reducing friction and wear for the friction pairs examined. At the same time, the grown self-repairing layers become more uniform as the duration of sliding between the two parts in a friction pair increases.