2016 Volume 9 Pages E16-014-1-E16-014-9
This paper describes an improvement of a measurement method of thermal conductivity in order to shorten the measurement time. A novel thermal interface material (TIM) which has both high electrical insulation performance and high thermal conductivity is strongly demanded. Especially, the novel TIM is strongly needed to achieve the electrical insulation between inverters and water cooling jacket in EVs (Electric Vehicles) and HEVs (Hybrid Electric Vehicles). In order to shorten the development period of the TIMs that has to do many times of the experiment to optimize the composition of the TIMs, an improvement of an evaluation method of the thermal conduction performance of the TIMs should be prepared. However, steady state measurement methods of thermal conductivity generally take very long time. Therefore, we have been focusing on an improvement of measurement method of thermal conductivity in order to achieve the reduction of the measurement time. In this paper, we developed the fast thermal conductivity measurement method by predicting steady temperature from transient temperature history in equipment. Through the investigation, it is found that steady temperature rise in the steady state thermal conductivity measurement can be predicted by using the transient temperature history of the steady state measurement. Information about the optimum time period of the measurement time of the transient temperature response to predict the correct steady state temperature can be obtained.