Fizika i Tekhnika Poluprovodnikov, 2022 Volume 56, Issue 2,Pages 173–177(Mi phts6991)
XVII Interstate Conference ''Thermoelectrics and Their Applications -- 2021" (ISCTA 2021 St. Petersburg, September 13-16, 2021)
Investigation of the influence of technological factors on the uncertainty of the results of measuring thermal conductivity by the method of laser flash
Abstract:
The estimation of the deviation in the measurements of thermal conductivity by the laser flash method for materials with different thermal conductivity coefficients, arising due to the presence of a graphite coating on the sample and the small thickness of the sample, is carried out. A computer model of the method was created in the Comsol Multiphysics software environment. For bulk samples with a graphite coating thickness of 20 $\mu$m, the deviation is 5.5%. The thickness of bulk samples does not affect the measurement results. For materials with low thermal conductivity, a sharp increase in the deviation is observed, reaching 60%. For thermally conductive materials, the deviation is 16–18%. For thin samples less than 10 $\mu$m thick, the thickness of the graphite coating does not affect the measurement results. The decisive factor is the duration of the laser pulse.