SIMPLE GUARDED HOT PLATE TECHNIQUE FOR MAKING THERMAL CONDUCTIVITY MEASUREMENTS OF COMPOSITE MATERIALS AT CRYOGENIC TEMPERATURES

摘要

There is an increasing requirement for the use of composite materials in applications at cryogenic temperatures, especially in spacecraft and liquid propellant propulsion systems. This paper reports on a simple technique for measuring the in-plane thermal conductivity of composite laminate materials between 4K- 300K. The measurement apparatus is constructed entirely within a 5cm diameter, 1.5m long evacuated stainless steel tube. The probe-like device is designed to be immersed in liquid helium contained in a standard transfer dewar. The thermal conductivity of various composite laminates was obtained at temperatures between 5K and 300K. The apparatus was calibrated using a NIST austenitic stainless steel standard reference material (1462). The results suggest that this novel approach is suitable for practical thermal conductivity measurements at cryogenic temperatures, while minimizing the usage of liquid helium.