ANGSTROM'S METHOD FOR SPREADING THERMAL CONDUCTIVITY MEASUREMENTS OF VAPOR CHAMBER

摘要

This study was tried to build up a measuring test platform to measure the thermal diffusivity of the vapor chamber by means of the Angstrom method.In addition, to obtain the spreading thermal conductivity (Ksp) of the vapor chamber, a specific heat capacity measuring device was designed as well.In general, Copper and Aluminum are usually applied in the cooler material due to the reason of the high thermal conductivity.Therefore, we used these thermal properties of these two materials as our calibration standard values.The results shown the relative error of the specific heat of the copper and aluminum samples were within 5％.The experiment results also shown the relative error of the thermal diffusivity of the copper was only 1.7％ when the distance was at 0.03m between two measuring thermocouples, while the relative error of the thermal diffusivity of the aluminum was 4.79％.The experiment result shown the temperature amplitude of the sine wave was increasing with increasing of the input power, and this was matched with the physical phenomena.Therefore, based on this test calibration philosophy, the spreading thermal conductivity for the copper vapor chamber and aluminum vapor chamber were 1390 W/m,K and 608 W/m,K respectively.