The Experimental Research On Measurement Of Thermal Contact Resistance Of Two Contacted Solids And Thermal Conductivity

Heat will pass through many interfaces when heat conducts from chips to heat sink in most of the electronic packaging. Contact thermal resistance among these interfaces will affect the thermal management performance and the reliability of these electronic devices. So far, most of the test equipments for thermal contact resistance measurement should be placed in a vacuum chamber, which results in unconvenient operation. Thermal conductivity is one of the basic thermal physical properties, it has wide application in electronic cooling, energy and chemical engineering. Precise measurement of thermal conductivity has important function for material selection.A low cost test setup for measuring thermal contact resistance was built in this paper, which is simple and easily operated compared with the existed apparatus. The above setup can also be used to measure thermal conductivities of solids after a slight change, two-layers method and three-layers method were used to measure thermal conductivities of materials in this paper.The effects of loading, heating power and temperature compensation on thermal contact resistance measurement were studied. It is found that the thermal contact resistance decreases as the laoding force increasing. The heating power does not have any effect on thermal contact resistance. Temperature compensation will affect the measurment accuracy. The experimental results were compared with theoretical analysis results, the results show that it has some difference. Error analysis were conducted and the method of decreasing error was proposed.According to above research, the setup of measuring thermal contact resistance was slightly changed to test thermal conductivity. Two layers method was used to measure thermal conductivities of aluminum alloy LY11 and brass H62, three layers method was used to measure thermal conductivities of epoxy, epoxy-copper and nylon1010. The results show that the mean relative error is between 2.75% and 4% by using this setup and test methods. So this setup is feasible for measuring thermal conductivities of other materials.