Effects of temperature on sliding wear process under contaminated lubricant test conditions

Six sliding wear tests have been conducted using a pin-on-disc tester to investigate the effects of temperature on sliding wear processes when the iron particle contaminants were existent or non-existent in the SAE40 lubricant. Ferrography analysis, particle size analysis using a CSI particle analyzer, numerical analysis on particle morphology based on confocal laser scanning microscope (CLSM) and surface examination of the tested samples using scanning electron microscope (SEM) were used to study the wear particles and the wear surfaces. Supported by data generated from the comprehensive analyses of the wear particles and the surfaces of the tested samples, it is clear that the temperature of the SAE40 lubricating oil has a significant influence on the wear processes. The increase in the temperature of the SAE40 lubricant increases the probability of adhesion, oxidation and wear rates. For the tests at elevated temperature, when the iron particles are added into the SAE40 lubricant, the degree of oxidation wear increases compared with the test without the iron particles in the SAE40 lubricant. This study has shown that temperature plays an important role in wear process and it is crucial to control temperature for controlling wear rates in sliding wear process.