The collision and friction between rotor and stator result in a harmful and complex physics process. Most of the mechanical energy dissipated by collision，and friction converts to heat. Even though each collision does not affect the rotor significantly, the decreasing of temperature takes a longer time in comparing with the vibration period of rotor. Once collisions take place constantly, the accumulated thermal effects must be taken into account. When the rotor passes through the critical speed, rub-impacts are liable to happen because of the rather large vibration amplitude. Collisions cause the variation of vibration phase, and the corresponding thermal bending prolongs the process of collisions. At first, a simplified model is set up to describe the elastic collision contact and friction between rotor and stator, and then an example is numerically computed and analyzed in order to examine the influence of rub-impact thermal effects on the vibration characteristics of a rotor passing the critical speed.