Abstract. The article substantiates two non-destructive testing methods — non-contact and contact — de-signed to determine the thermophysical properties of materials by locally heating a semi-infinite medium using a disk-shaped heat source. During processing of the heating thermogram obtained with a non-contact source, the homochronicity parameter is used, defined as the ratio of the average rates of surface tempera-ture change taken from different sections of the heating thermogram. It is established that, for certain geo-metric dimensions of the heat source and temperature measurement points, the homochronicity parameter ε is functionally related to the product of the material’s thermal diffusivity and the temperature measurement time. This makes it possible, using nomograms derived from preliminary numerical calculations for a series of materials with known thermophysical properties, to determine the thermal diffusivity and thermal conduc-tivity coefficients of the test materials without employing complex methods for solving inverse heat conduc-tion problems.
The contact method involves time-resolved detection of the excess temperature at the center or at a certain distance from the disk-shaped heat source, and interpretation of the temperature profile using nomograms obtained with consideration of the heater’s heat capacity and the homochronicity parameter values, or by means of a neural network that establishes a relationship between the heating thermogram parameters and the target thermophysical properties.

Keywords: thermal non-destructive testing methods, non-contact method, contact method, homochronicity parameter, nomograms, neural network

For citation: Brovka G. P., Lysenko S. A., Agutin K. A., Murashko A. A., Brovka A. G. Non-destructive test-ing methods for determining thermophysical properties of materials. Aerospace Engineering and Technology. 2025. Vol. 3, no. 4, pp. 672–687. https://doi.org/10.52467/2949-401X-2025-3-4-672-687; https://elibrary.ru/BYOWPW (In Russian)

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