Abstract
We have been developing an improved in-plain thermal conductivity measuring method of flat plate specimen such as printed wiring board (PWB) named as "quasi-steady state straight fin temperature fitting method" in which transient temperature data are used to obtain temperature dependency of the thermal conductivity of the specimen by only one time heating. We demonstrated the accuracy of the measurement method by experiment and numerical simulation. Three kinds of metals such as pure copper, pure aluminum and stainless steel were used as specimens in which fin efficiency were ranged from 0.09 to 0.75. The following conclusions were obtained from the experiment and the numerical simulation. (1) As specimen temperature rises, the temperature profile changed analogously after a certain time after start of heating. (2) The temperature profile reached steady state condition at 3600s after heating but thermal conductivity obtained by this method showed constant value after 400s. (3) The effective thermal conductivity obtained by this method agreed with the literature data within ±10% dispersion in the fin efficiency ranges of 0.2〜0.8.
