Abstract A 3D analytical solution is proposed in this paper to determine the temperature and the partition coefficient of heat flux generated by friction in a pin-on-disc tribometer. This solution is valid without restriction on the rotational velocity of the disc. It is given under an explicit form, thus avoiding any iterative calculation. A validation is performed by comparing the results with those available for a circular heat source in rectilinear motion. Thermal maps of the disc are presented for different values of its rotational velocity. The evolution of the temperature and the heat partition coefficient are presented and analysed as a function of the disc velocity and the cooling conditions.