Development of techniques to determine temperature coefficient of resistance

Abstract

The focus of this thesis was to develop a simple, repeatable method for characterizing the relationship of different materials' electrical resistance with respect to temperature. A measurement of this relationship is the temperature coefficient of resistance (TCR). Determining the TCR allows a material to be used as a temperature probe and can be utilized in thermal conductivity measurements. The test apparatus and measurement setup proved capable of determining the temperature coefficients of resistance of a copper-alloy wire and a carbon film resistor, giving TCR values of 0.0036 1/K and -0.00014 1/K, which was consistent with their published values. The work of this project aims to aid in the development of a micro-cooling system, which uses polycarbonate for its heat exchanger at cryogenic temperatures. A potential carbon film temperature probe was tested, but was found to be unfit for the intended use as a temperature probe on a polycarbonate surface due to catastrophic failures in the film, most likely caused by the different thermal expansion rates of the carbon and polycarbonate. Further research should be conducted to first find a more suitable temperature probe for polycarbonate and then conduct tests at cryogenic temperatures.