A novel method of measuring temperatures due to sliding in ultra-high vacuum

An apparatus was designed and built for the measurement of temperatures due to friction near the interface of two sliding objects. The sliding specimen is electromagnetically suspended and rotated in the suspended position. The only elements in contact with the slider are the rider specimens which act not only as friction sources but also as bearings, guiding the rotating slider. Temperature probes in the slider are temperature sensitive resistors in a transmitter circuit. As their temperature changes, so does the frequency of transmission. In this way, temperatures are transmitted outside the system without introducing any additional contacts. Temperatures on the rider are measured with thermocouples. The normal force on the slider due to the rider and the total torque in the system are also measured. Temperatures are measured both in air and in vacuum. A simplified configuration was chosen for each the slider and the rider. The theory is developed to enable the usage of the measured temperatures as boundary points and the radiation constant as a parameter in calculating the interface temperatures.