Composite specific heat measuring device by black body method

Abstract

The invention discloses a composite specific heat measuring device by a black body method. A variable diaphragm (2) is arranged behind the illuminating end of a laser light source (1); a light splitter (4) is arranged behind the variable diaphragm (2); a laser energy sensor (13) corresponds to the light splitter (4); a focusing lens (5) is arranged behind the light splitter (4); the top end of a shell (7) with energy sensor function is provided with a small hole (6); a temperature sensor (9) is arranged on a sample (8); three channels of a three-channel amplifier (10) are electrically connected with the temperature sensor (9), the shell (7) with energy sensor function and the laser energy sensor (13) respectively, and the three-channel amplifier (10) is electrically connected with a computer (12) by a data acquisition card (11). The composite specific heat measuring device by a black body method has high precision and high reliability of measurement of specific heat and heat conduction coefficients without carrying out any surface processing on a sample to be measured.

Description

technical field [0001] The invention relates to a laser specific heat testing device, in particular to a composite black body method measuring specific heat device. Background technique [0002] At present, while the laser flash method (Flash Method) is used to measure the thermal diffusivity of materials at home and abroad, the specific heat measurement generally adopts the comparison method. After patch or coating treatment, the first step is to irradiate the surface of the standard sample with a laser, and measure the maximum temperature rise on the back. The product of this temperature rise and the known mass and specific heat is the laser energy absorbed by the standard sample; The second step is to treat the surface of the sample to be measured in the same way, and irradiate it with the same energy laser, and also measure the maximum temperature rise on the back side. If it is assumed that the absorbed energy is equal to that absorbed by the standard sample, the speci...

AI Technical Summary

Problems solved by technology

Theoretical analysis and practice show that inconsistencies in surface treatment cause differences in absorptivity, resulting in large errors in specific heat tests

At the same time, due to the need for standard samples, two sample surface treatments and two laser irradiations are required, which complicates the experimental process and increases the experimental cost.

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