EVALUATION OF THE LUBRICATING PROPERTIES OF ENGINE OIL MODIFIED WITH REVITALIZERS

Abstract

 This study investigates the lubricating properties of synthetic SAE 5W-30 engine oils modified with a revitalizing additive under boundary lubrication conditions. The objective was to evaluate the influence of the revitalizer on friction and wear characteristics and to determine the effect of load on tribological performance. Experimental tests were carried out using the four-ball method according to DIN 51 350 standard at loads of 150 N and 300 N. During testing, friction torque and temperature were recorded, the coefficient of friction was calculated, and wear scar diameters were measured after each test. Statistical analysis included the calculation of arithmetic means, standard deviations, and 95% confidence intervals.

The results showed that increasing load intensified friction processes and heat generation, making the tribological system more sensitive to additive effects. The effectiveness of the revitalizer depended on the base oil composition. For one oil, no statistically significant changes were observed, whereas for the other oil a reduction in friction torque and wear was detected at 300 N load. The findings indicate that the revitalizer effect is not universal and becomes more pronounced under higher contact loads, where tribochemical processes and potential tribofilm formation are more active.