METHOD FOR MEASURING THERMAL CONDUCTIVITY AND CONTACT RESISTANCES OF MULTILAYER NANOPOROUS MATERIALS Russian patent published in 2023 - IPC G01N25/18 B82B1/00 B82Y40/00 

FIELD: measuring technology.

SUBSTANCE: invention relates to methods for measuring the thermophysical properties of composite materials, in particular multilayer substrates for power printed circuit boards, and can be used to evaluate and calculate thermal resistance during the development and manufacture of these substrates. A method for determining the thermal conductivity and thermal resistance of multilayer nanoporous materials by the method for stationary heat flow is claimed, consisting in registering the thickness of the sample represented by the substrate, coating the test substrate with a sheet of copper foil 0.05 mm thick on both sides, and the foil sheet covers the end surfaces of the substrate, coating the test substrate with thermal paste on both sides, placing the substrate between two metal measuring rods with an array of thermocouples, application of clamping pressure, temperature recording of metal measuring rods, the surface area of the substrate, the distances between the thermocouples in the metal rods, as well as the distances between the thermocouples and the lower and upper surfaces of the substrate. Moreover, the calculation of the average heat flow through the substrate, the values of the temperature of the lower surface of the sample and the temperature of the upper surface of the sample, as well as the thermal resistance is carried out by varying the thickness of the substrate, while the thermal resistance is determined from the analytical dependence, and the thermal conductivity is determined from the graph of the dependence of thermal resistance on the thickness of the substrate, which is a straight line, the tangent of the angle of inclination of which is the inverse of the desired thermal conductivity.

EFFECT: simplification of the experiment procedure, reduction of preparation time for it and acceleration of obtaining the measurement results.

1 cl, 1 dwg, 2 tbl