This work concerns the use of a unique macroscopic tribometer to take cryogenic friction measurements of a variety of coatings. This tribometer operates in ultrahigh vacuum (UHV), removing the potential lubricating effects of immersion in cryogenic liquids. Mechanical gauges such as strain gauges tend to lose calibration or fail entirely in a sufficiently low temperature setting, therefore this tribometer was designed to measure friction via analysis of high speed video taken of a block sliding down a ramp. A chameleon coating, molybdenum disulfide + titanium, provides a glimpse at the cryogenic behavior of the strategy of combining the positive aspects of several different materials in a lubricating coating. Study of several carbon-based, sp 3-bonded coatings in vacuum and at low temperatures provides insight into the influence of surface hydrogen termination on the coefficient of friction. The effect of superconductivity is explored using a niobium track with niobium and steel counterfaces, demonstrating no effect on the coefficient of friction on the macroscopic scale. Finally, the lubricating effects of a helium gas environment at 2 Kelvin were explored, showing very little, if any, effect on the coefficient of friction.
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