Using infrared imaging to measure the friction coefficient during pin-on-disk sliding wear tests

In a standard pin on a disk tribometer, the friction coefficient under a sliding wear configuration is commonly obtained from the experimental measurement of the tangential force, which is usually achieved through either a load cell attached to the pin holder or a torque meter attached to the disk shaft. This paper presents an alternative method to measure the friction coefficient using a combination of thermal imaging and a reverse thermal model. The measurement of the temperature evolution of the pin, allow to solve the friction heat generation problem between the mating surfaces. Heat generation is influenced by the friction coefficient and the test parameters, whilst conduction is also significantly affected by the thermophysical properties of the materials. Experimental tests with PTFE pins with lamellar bronze filler and Cr2O3-coated stainless steel disks showed an average difference of the friction coefficient of about 12% between the new thermal and the standard measurement.