Method for testing thermal resistance and heat conductivity coefficient of material

Abstract

The invention relates to a method for testing the thermal resistance and the heat conductivity coefficient of a material. The method comprises the following steps: arranging a to-be-tested material on a constant-temperature heat sink; mounting the MOSFET power device on the material to be tested; heating the MOSFET power device until a heat flow transmission path reaches heat balance, and recording a first heating curve of the voltage of the MOSFET power device along with time by using thermal resistance test equipment; removing the to-be-tested material, and mounting the MOSFET power device on the constant-temperature heat sink; heating the MOSFET power device until a heat flow transmission path reaches heat balance, and recording a second heating curve of the voltage of the MOSFET power device along with temperature change by using thermal resistance test equipment; the thermal resistance of the to-be-measured material is calculated through fitting according to the first heating curve and the second heating curve; and determining the heat conductivity coefficient of the to-be-tested material according to the thermal resistance.

Description

technical field [0001] The invention relates to the field of material thermal property testing, in particular to a testing method for material thermal resistance and thermal conductivity. Background technique [0002] The thermal conductivity of a material is an inherent property of the material itself, which is not only related to the material type of the material, but also closely related to the material's microstructure and filler content. In practical scientific experiments and engineering design, there are many test methods for thermal conductivity, and these methods have different requirements for applicable fields, measurement ranges, precision, accuracy and sample size. At present, the main methods of material thermal conductivity testing are steady-state and non-steady-state. In the field of thermal grease, the steady-state hot plate method (reference standard: ASTM D5470) and the transient plane heat source method (reference standard ISO 22007-2) are mainly used. ...

AI Technical Summary

Problems solved by technology

The steady-state hot plate method has the following problems: it has certain requirements on the thickness of the material and the size of the sample, and at the same time it is difficult to control the power consumption of the heat source, and its measurement range and accuracy have certain limits

There are also certain problems in the transient test: for example, this method is only suitable for testing the thermal conductivity of homogeneous materials, and is not suitable for measuring anisotropic materials, such as graphite sheets

At present, there are a large number of thermal conductivity test methods, but none of them can be applied to all products, all occasions, or at least most products and occasions, and product characteristics, test standards, test environments, etc. will affect the results of thermal conductivity

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