Local temperatures evaluation on the pin–disc interface using infrared metrology

Abstract

This paper presents the development of an infrared metrology to evaluate local temperatures in sliding contact. A pin-on-disc tribometer was adapted for this purpose. The originality of this metrology is the use of a pin comprising a transmissive infrared window and an optical fiber two-color pyrometer. Local temperatures are evaluated at the pin–disc interface thanks to the optical fiber inserted in the pin. The experimental local temperatures correlate well with the disc surface temperature calculated with an analytical solution found in the literature for a pin-on-disc frictional device. In addition, disc temperature at the exit from the contact area is measured by a monochromatic pyrometer. The monochromatic temperature is corrected by taking into account the emissivity obtained by two-color pyrometry. Results show that the difference between the local temperatures in the pin-disc contact area and the corrected temperature obtained by the monochromatic pyrometry at the exit from the contact area remains weak. Besides, a good correlation was found between the local contact temperature and the friction torque. Thus, the knowledge of the local contact temperature is necessary to determine the modification of the tribological behavior at the pin-on-disc interface.