Precise Measurement of Thermophysical Properties of Solids by a Direct Electrical Heating Method (Measurement of Thermal Diffusivity and Theoretical Evaluation of Accuracy)

Abstract

The final goal of this study is to develop a multipurpose measurement system, which can simultaneously obtain thermal conductivity, total hemispherical emittance, thermal expansion, thermal diffusivity and specific heat by a direct electrical heating method. In this report, the principle of the newly-developed method for measuring thermal diffusivity is described. Rod samples of silver (purity 99.99%) and austenitic stainless steel (JIS SUS 304) of 200 mm in length and 1.494 mm in radius are used in order to verify the applicability of this method. Theoretical evaluations of errors in this measurement are also conducted. From the experimental results and their evaluation, it becomes clear that this method is satisfactory for precisely measuring the thermal diffusivity of a rod sample.