Development of a heating system and the effect of temperature in the twin-disc test

Although temperature is an important variable in tribosystems, its monitoring and control are constantly neglected by studies that use the twin-disc test to simulate the interactions that occur at the wheel-rail interface. In this study, a heating system was developed that allows the performance of tests with temperature control. For validation, tests were performed from room temperature to 80 °C. These tests demonstrated the operation of the heating system and the effect of temperature in the twin-disc test. Under the test conditions at a temperature of 70 °C, the mass loss was 36% lower than that of the test at room temperature. In discs A (wheel), the formation of black oxides with lubricating characteristics was observed and consequent reduction in wear for tests at higher temperature. On the other hand, in discs B (rail), the condition of lower mass loss coincides with a less degraded surface and with fewer and smaller cracks. The post-test roughness of the disc B (rail) was independent of the temperature; however, the roughness of the disc A (wheel) suffered a slight rise with an increase in temperature. The roughness of the discs B was also lower than that of the discs A.