Thermal conductance of pressed contacts at liquid helium temperaturesIt is pointed out that the optimum design of cryogenic instruments requires accurate thermal models. The present models are limited by a lack of knowledge of the low temperature thermal conductance of the bolted joints which are typically used in the instrument-to-system interface. In connection with studies of pressed contacts, it has been found that the thermal conductance does not obey the Wiedemann-Franz law. The present investigation is concerned with the characterization of the thermal conductance of pressed contacts at liquid helium-4 temperatures, taking into account the dependence of thermal contact conductance on applied force and temperature. It is shown that for the 0.4 micron OFHC copper pressed contact pair, the thermal conductance varies roughly as the second power of the temperature, and increases with increasing applied force.
Document ID
19830051490
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Salerno, L. J. (NASA Ames Research Center Moffett Field, CA, United States)
Kittel, P. (NASA Ames Research Center Moffett Field, CA, United States)
Spivak, A. L. (Trans-Bay Electronics, Inc. Richmond, CA, United States)