Heat barrier material high temperature heat conductivity plane heat source test system and method

Abstract

The invention provides a heat barrier material high temperature heat conductivity plane heat source test system and method, and heat barrier material heat conductivity at the temperature of room temperature to 1200 DEG C can be tested. Three stacked to-be-tested samples are placed in a high temperature furnace, a plane heat source providing a constant power output is placed between a middle sample and a lower sample, the plane heat source is connected with a constant flow source meter by a high temperature resistant wire, a temperature testing thermocouple responding test temperature is arranged between an upper sample and the middle sample, and the temperature testing thermocouple is connected with a temperature display instrument. After the high temperature furnace is heated, the plane heat source is charged with a step type heating current, and temperature change of the temperature testing thermocouple is tested and recorded under constant pressure so as to calculate the heat conductivity of the to-be-tested sample. The plane heat source and the temperature testing thermocouple can solve the problem of temperature signal interference during test of heat conductivity of a low resistivity material by use of transient plane source method, and can achieve test of high temperature heat conductivity of the low resistivity material.

Description

technical field [0001] The invention belongs to the testing field of heat insulation materials, and specifically provides a test system and method for a plane heat source of high temperature thermal conductivity of heat insulation materials suitable for heat insulation materials at any temperature from room temperature to 1200°C. Background technique [0002] The test methods for thermal conductivity of insulation materials mainly include steady-state flat plate method, transient plane heat source method, transient hot wire method, transient hot-line method, transient hot plate method, transient laser pulse method, etc. The steady-state plate method is mainly used to test materials with a thermal conductivity below 1W / m·K, but its achievable test temperature is not high, and the highest test temperature reported does not exceed 800°C. The transient method can generally achieve higher temperature testing, but these methods also have certain limitations, such as the plane heat...

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Problems solved by technology

For example, a polymer (such as polyimide) insulating film is used to cover the heat source, but due to the low heat resistance temperature of most organic materials, the use temperature of this type of heat source is limited, generally the upper limit is 200-300 ° C, more than It will coke at the upper temperature limit and lose its insulation performance

There are also researchers who test the thermal conductivity of this type of material by coating the surface of the heat source with a high-temperature insulating coating. It cannot be ignored, and the time delay of the thermal signal generated by it is difficult to quantitatively describe in the calculation of thermal conductivity

Although the transient laser pulse method can be used to test the thermal conductivity of non-insulating materials, and the maximum test temperature is as high as 3000°C, it is less than 3×10 for thermal diffusivity. -7 K / m 2 Materials, especially infrared-transmitting insulation materials such as silica and alumina aerogels, are no longer applicable

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