METHOD OF MEASURING THERMAL CONDUCTIVITY OF SOLID MATERIALS

摘要

FIELD: test technology.;SUBSTANCE: invention relates to thermal tests, namely to the determination of the thermal conductivity of materials. Method for measuring the thermal conductivity of solid materials is proposed, which includes preparation of a sample from a material under study in the form of a rod of constant cross section, creation of a given temperature drop at the ends of the sample by regulating the power of the heaters and determining the desired value using the mathematical dependence from the results of measuring the temperature difference at the ends of the sample and the power of the heaters after reaching a steady-state heat transfer condition. In this case, the ends of the sample are placed in separate cells of a calorimeter, each calorimetric cell is insulated, supplied with the same electric heaters and individual heat sink. Preliminarily without a sample, the calibration dependences of the heat flux on the temperature for each cell are determined, the heaters of both cells are supplied with a periodic discharge of the connected to them common capacitor, regulating the supply of various energy values to the heaters, determined by the number of power pulses and by measuring the capacitor voltage before each pulse, and regulating the power released on the heaters by changing the number of pulses per time unit. Thermal conductivity is determined on the basis of the thermal balance of each cell under steady-state conditions.;EFFECT: higher accuracy of determining the desired parameter and expansion of the temperature range in which measurements are taken.;1 cl, 2 dwg