Temperature control diaphragm based high temperature material spectral emissivity measuring device and measuring method

Abstract

The present application belongs to the field of optical measurement and test, and discloses a high-temperature material spectral emissivity measuring device and method based on a temperature-controlled diaphragm. The measuring device is composed of a standard black body, a temperature-controlled diaphragm, an electrically-controlled rotating mirror, a sample heating furnace, a three-dimensional platform, an optical collimation system and a Fourier transform infrared spectrometer. The present application adopts a liquid circulation type temperature-controlled diaphragm, and the surface temperature of the diaphragm is the same as the laboratory environment temperature. In the spectral emissivity measurement, a diffuse reflection plate with a reflectivity of 1 does not need to be introduced, and a vacuum constant temperature system is also not needed. The present application can eliminate the influence of environmental radiation and atmospheric transmittance, and improve the spectral emissivity measurement precision. The present application designs a gradual diaphragm to realize the selection of the effective detection area of the material sample, and realizes the high dynamic range measurement of the infrared radiation signal in a wide temperature range.

Description

Technical Field

[0001] This invention belongs to the field of optical metrology and testing, and relates to a device and method for measuring the spectral emissivity of high-temperature materials, particularly a device and method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture with a temperature range of 1273K to 3100K. Background Technology

[0002] Spectral emissivity is a crucial parameter describing the thermal radiation characteristics of an object. Accurate spectral emissivity data holds significant scientific and practical value in fields such as power equipment, new materials, and optoelectronic countermeasures. In power equipment, the spectral emissivity of the collector tube coating is a fundamental technical indicator determining solar energy absorption rate and a key factor in the efficiency of solar thermal power generation systems. In new materials, testing the thermal radiation performance of various new materials, such as building solar radiation control coatings, carbon fiber heating materials, graphene flexible heating films, and novel heat-resistant protective coatings with infrared radiation capabilities, helps promote the development of energy conservation and environmental protection in my country. In optoelectronic countermeasures, spectral emissivity is an important parameter for evaluating infrared stealth performance. By developing low-emissivity materials and coatings, the infrared radiation of targets can be reduced, lowering the probability of detection / tracking by enemy infrared optical systems and improving defensive and survivability capabilities.

[0003] Material emissivity depends not only on its composition and surface condition (roughness, oxidation, etc.), but also on factors such as temperature, wavelength, and observation direction. In recent years, with the development of infrared detection technology, especially the widespread application of Fourier transform spectrometers in spectral emissivity measurement, the accuracy of spectral emissivity measurement has been greatly improved. Currently, when using the energy comparison method to test the spectral emissivity of materials, it is often necessary to test the voltage signal of the diffuse reflector, which affects the accuracy of the spectral emissivity measurement. For example, the paper titled "Research and Error Analysis of a Measurement Device for Directional Spectral Emissivity of Solid Materials" published in Volume 31, Issue 4 of *Applied Optics* analyzes and introduces a proposed emissivity measurement model based on the energy method, and establishes a measurement device for directional spectral emissivity of solid materials. It uses an approximate measurement with a diffuse reflector coefficient of 1 to obtain the directional spectral emissivity of solid materials in the temperature range of 50℃~300℃ and the spectral range of 1.3μm~14.5μm. Summary of the Invention

[0004] (I) Purpose of the Invention

[0005] The purpose of this invention is to provide a device and method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture, in order to meet the requirements of high-precision material spectral emissivity measurement.

[0006] (II) Technical Solution

[0007] To address the aforementioned technical problems, this invention provides a high-temperature material spectral emissivity measurement device based on a temperature-controlled aperture. This device includes: a standard blackbody 1, an electrically controlled rotating mirror 3, a sample heating furnace 4, an optical collimation system 6, and a Fourier transform infrared spectrometer 7. The standard blackbody 1 is arranged on one side of the electrically controlled rotating mirror 3, and the sample heating furnace 4 is arranged on the opposite side. The optical collimation system 6 is arranged on the reflective side of the electrically controlled rotating mirror 3. The sample to be measured is arranged inside the sample heating furnace 4. The reflective surfaces of the electrically controlled rotating mirror 3 are sequentially switched, respectively converting the effective radiating surfaces of the standard blackbody 1 and the sample to the focal position of the optical collimation system 6. The thermal radiation signals of the standard blackbody 1 and the sample are collimated by the optical collimation system 6 to form a collimated beam, which is received by the Fourier transform infrared spectrometer 7. The Fourier transform infrared spectrometer 7 uses the interference principle to perform interference splitting of the incident light, forming an interference phase distribution. This distribution is then converged by an imaging mirror and received by an infrared detector. The spectral information is then recovered through Fourier transform.

[0008] It also includes two temperature control apertures: a first temperature control aperture 20 and a second temperature control aperture 21. The first temperature control aperture 20 is set at the thermal radiation outlet of the standard blackbody 1, and the second temperature control aperture 21 is set at the thermal radiation outlet of the sample heating furnace 4.

[0009] It also includes: a three-dimensional platform 5, a sample heating furnace 4 installed on the three-dimensional platform 5, the built-in laser of the infrared Fourier transform spectrometer 7 is turned on so that the laser backlight path is incident on the surface of the sample being tested, and the three-dimensional platform 5 is adjusted so that the laser point in the infrared Fourier transform spectrometer 7 is located at the center of the surface of the sample being tested.

[0010] The standard blackbody 1 includes a graphite tube blackbody cavity, a temperature-controlled radiation thermometer, a temperature controller, and a power supply. The graphite tube blackbody cavity employs a direct resistance heating principle based on graphite elements, connected to water-cooled copper electrodes at both ends of a graphite ring. The power supply heats the graphite tube, which has an external conical structure. The blackbody cavity is evacuated and filled with argon gas. Both ends of the graphite tube have extended sealed cavities, with window flanges installed on both sides, and quartz and KBr windows respectively. The temperature-controlled radiation thermometer is a photoelectric pyrometer. During measurement, the optical imaging system at the front end of the photoelectric pyrometer is adjusted to focus the pyrometer on the bottom of the blackbody cavity target to complete the temperature measurement. The temperature controller adjusts the power supply's heating power according to the set temperature value and the photoelectric pyrometer's measurement value, while also providing control for water cooling circulation and argon filling.

[0011] The first temperature-controlled aperture 20 and the second temperature-controlled aperture 21 have the same structure, both including a constant-temperature liquid temperature controller, a centrally-aperture cubic aperture 8, an electrically controlled temperature-controlled shutter 9, and a temperature measurement module. The constant-temperature liquid temperature controller is connected to the pipe interface 10 of the centrally-aperture cubic aperture 8 through a liquid transmission pipe, and uses a liquid circulation temperature control method to control the surface temperature of the aperture to be the same as the laboratory ambient temperature. The central aperture of the centrally-aperture cubic aperture 8 is made of an arc-shaped blade with a continuously adjustable aperture diameter. The electrically controlled temperature-controlled shutter 9 has a cylindrical structure and is connected to the centrally-aperture cubic aperture 8 through a liquid transmission pipe. The surface temperature of the electrically controlled temperature-controlled shutter 9 is the same as the laboratory ambient temperature. The temperature measurement module measures the laboratory ambient temperature in real time and feeds it back to the constant-temperature liquid temperature controller so that the constant-temperature liquid temperature controller can adjust the circulating liquid temperature.

[0012] The electrically controlled rotating reflector 3 includes a gold-plated plane reflector, an electrically controlled rotating platform, and an electrically controlled shifting stage controller. The gold-plated plane reflector is mounted on the electrically controlled rotating platform, and the electrically controlled shifting stage controller controls the working state of the electrically controlled rotating platform. The electrically controlled rotating platform drives the gold-plated plane reflector to achieve optical path switching.

[0013] The sample heating furnace 4 uses electric heating to heat the graphite plate. The electrodes at both ends of the graphite plate are cooled by water cooling. The sample to be tested is installed in a fixed workpiece, which is supported by two graphite support rods. The two graphite support rods are placed parallel to each other in front of the graphite plate, and the sample is heated by radiative heat transfer.

[0014] The sample heating furnace 4 has a water-cooled jacket and is coated with a high emissivity coating inside it.

[0015] The main material of the three-dimensional platform 5 is aluminum alloy, which is subjected to black anodizing treatment; the optical collimation system 6 adopts a total internal reflection structure, which consists of an aspherical mirror and a plane mirror. The effective radiation surface of the standard blackbody 1 and the sample under test is located at the focal point of the optical collimation system. The thermal radiation signals of the two are formed into a collimated beam after passing through the optical collimation system and are received by the Fourier transform infrared spectrometer; the Fourier transform infrared spectrometer 7 uses the interference principle to perform interference and spectral dispersion on the incident light, forming an interference phase distribution. The phase distribution is received by the infrared detector under the convergence of the imaging mirror, and the spectral information can be recovered after Fourier transform.

[0016] This invention also provides a method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture. The measurement method is implemented using the aforementioned measuring device, and the process is as follows:

[0017] (1) The sample to be tested is clamped on the sample heating furnace 4, the thermocouple thermometer is inserted into the side opening of the sample, the sample heating furnace is installed on the three-dimensional platform 5, the built-in laser of the infrared Fourier transform spectrometer 7 is turned on, so that the laser backlight path is incident on the surface of the sample to be tested, and the three-dimensional platform 5 is adjusted so that the laser point in the infrared Fourier transform spectrometer 7 is located at the center of the material sample surface, and the material sample clamping adjustment is completed.

[0018] (2) Turn on the controllers of the standard blackbody 1, sample heating furnace 4, and electric rotating reflector 3 in sequence. Set the spectral range of the high-temperature material spectral emissivity measurement device to 1μm~15μm, the wavelength interval to 0.1μm, and the temperature measurement point to T. Start the test after the standard blackbody 1 and the material sample temperature stabilize.

[0019] (3) Open the electronic shutter of the temperature-controlled aperture 2 at the front end of the standard blackbody 1, control the electronic rotating mirror 3 to rotate so that the radiation from the standard blackbody 1 enters the optical path, and read the output signal of the standard blackbody 1:

[0020] V i (λ, T) = K(λ){τ(λ)[ε B (λ,T)L b (λ,T)+[1-ε B (λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )}

[0021] In the formula V i (λ, T) is the output signal of the standard blackbody 1, ε B (λ, T) is the standard blackbody spectral emissivity, L b (λ,T) represents the spectral radiance of a standard blackbody at wavelength λ and temperature T, where L b (λ,T a () represents wavelength λ and temperature T a In the case of a standard blackbody, τ(λ) is the atmospheric transmittance, and K(λ) is the responsivity of the Fourier transform infrared spectrometer.

[0022] (4) Open the electronic shutter of the temperature control aperture 2 at the front end of the sample heating furnace 4, control the electronic rotating mirror 3 to rotate so that the infrared material sample radiation enters the optical path, and read the output signal of the material sample at the same temperature and wavelength as the standard blackbody 1:

[0023] V i ′(λ,T)=K(λ){τ(λ)[ε′ M (λ,T)L b (λ,T)+[1-ε′M (λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )}

[0024] In the formula V i ε′(λ, T) is the output signal of the material sample, ε′ M (λ, T) represents the spectral emissivity of the material sample;

[0025] (5) Close the electric shutter 9 of the temperature control aperture 2 to make the temperature of the electrically controlled surface the same as the laboratory ambient temperature, and measure the background signal.

[0026] V0(λ,T)=K(λ){τ(λ)[ε0(λ,T)L b (λ,T a )+[1-ε0(λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )} =K(λ){τ(λ)L b (λ,T a )+(1-τ(λ))L b (λ,T a )}

[0027] In the formula, V0(λ,T) is the background signal, and ε0(λ,T) is the spectral emissivity of the surface of the temperature-controlled aperture electronic shutter;

[0028] (6) By rearranging the above formula, we can calculate the spectral emissivity of the material sample using the definition of spectral emissivity:

[0029] V i ′(λ,T)-V0(λ,T)=K(λ)τ(λ)ε′ M (λ,T)[L b (λ,T)-L b (λ,T a )]

[0030] V i ()λ,T)-V0()λ,T)=K(λ)τ(λ)ε B (λ,T)[L b (λ,T)-L b (λ,T a )]

[0031]

[0032] (III) Beneficial Effects

[0033] The above-mentioned technical solution provides a high-temperature material spectral emissivity measurement device and method based on a temperature-controlled aperture, which has the following beneficial effects:

[0034] (1) A liquid-circulating temperature-controlled aperture is used, and the surface temperature of the aperture is the same as that of the laboratory environment. When measuring spectral emissivity, there is no need to introduce a diffuse reflector with a reflectivity of approximately 1, nor is a vacuum constant temperature system required. This eliminates the influence of environmental radiation and atmospheric transmittance, thereby improving the accuracy of spectral emissivity measurement.

[0035] (2) A gradient aperture is designed to select the effective detection area of ​​the material sample, thereby enabling high dynamic range measurement of infrared radiation signals over a wide temperature range. Attached Figure Description

[0036] Figure 1 This is a diagram showing the composition of the high-temperature material spectral emissivity measurement device of the present invention.

[0037] Figure 2 These are diagrams of the key components of the temperature control aperture of this invention. Diagrams A and B show two different view angles. Detailed Implementation

[0038] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0039] like Figure 1 As shown, the high-temperature material spectral emissivity measurement device based on a temperature-controlled aperture in this embodiment of the invention includes a standard blackbody 1, an electrically controlled rotating mirror 3, a sample heating furnace 4, an optical collimation system 6, and a Fourier transform infrared spectrometer 7. The standard blackbody 1 is arranged on one side of the electrically controlled rotating mirror 3, and the sample heating furnace 4 is arranged on the opposite side. The optical collimation system 6 is arranged on the reflective side of the electrically controlled rotating mirror 3. The sample to be measured is arranged inside the sample heating furnace 4. The reflective surfaces of the electrically controlled rotating mirror 3 are switched sequentially to convert the effective radiation surfaces of the standard blackbody 1 and the sample to be measured to the focal position of the optical collimation system 6. The thermal radiation signals of the standard blackbody 1 and the sample to be measured form a collimated beam after passing through the optical collimation system 6 and are received by the Fourier transform infrared spectrometer 7. The Fourier transform infrared spectrometer 7 uses the interference principle to perform interference and spectral dispersion on the incident light, forming an interference phase distribution. The beam is received by the infrared detector under the convergence of the imaging mirror and the spectral information is restored after Fourier transform.

[0040] The measuring device in this embodiment also includes two temperature control apertures: a first temperature control aperture 20 and a second temperature control aperture 21. The first temperature control aperture 20 is set at the thermal radiation outlet of the standard blackbody 1, and the second temperature control aperture 21 is set at the thermal radiation outlet of the sample heating furnace 4.

[0041] The measuring device in this embodiment also includes: a three-dimensional platform 5, a sample heating furnace 4 installed on the three-dimensional platform 5, the built-in laser of the infrared Fourier transform spectrometer 7 is turned on so that the laser backlight path is incident on the surface of the sample to be measured, and the three-dimensional platform 5 is adjusted so that the laser point in the infrared Fourier transform spectrometer 7 is located at the center of the surface of the sample to be measured.

[0042] In this embodiment, the standard blackbody 1 includes a graphite tube blackbody cavity, a temperature-controlled radiation thermometer, a temperature controller, and a power supply. The graphite tube blackbody cavity employs a direct resistance heating principle based on graphite elements. Water-cooled copper electrodes connected to both ends of the graphite ring are used to directly heat the graphite tube using a large AC current and low voltage. The graphite tube adopts an external conical structure design to reduce the local cross-sectional area at the blackbody cavity opening, thereby increasing local resistance and heat generation, compensating for heat loss at the cavity opening, and effectively reducing the temperature gradient on the blackbody cavity wall. To prevent high-temperature oxidation of the graphite, the blackbody cavity is evacuated and filled with argon gas. Both ends of the graphite tube adopt an extended sealed cavity structure design, with window flanges installed on both sides of the extended cavity, and quartz windows and KBr windows installed respectively. The temperature-controlled radiation thermometer is a photoelectric pyrometer. During measurement, the optical imaging system at the front end of the photoelectric pyrometer is adjusted so that the photoelectric pyrometer focuses on the bottom of the blackbody cavity target to complete the blackbody cavity temperature measurement. The temperature controller adjusts the power supply heating power according to the set temperature value and the measurement value of the photoelectric pyrometer, and at the same time provides control operation for water cooling circulation and argon filling.

[0043] like Figure 2 As shown, the first temperature-controlled aperture 20 and the second temperature-controlled aperture 21 have the same structure, both including a constant-temperature liquid temperature controller, a centrally-aperture cubic aperture 8, an electrically controlled temperature-controlled shutter 9, and a temperature measurement module. The constant-temperature liquid temperature controller is connected to the pipe interface 10 of the centrally-aperture cubic aperture 8 via a liquid transmission pipe, and uses a liquid circulation temperature control method to ensure that the surface temperature of the aperture is the same as the laboratory ambient temperature. The central aperture of the centrally-aperture cubic aperture 8 is made of an arc-shaped blade with a continuously adjustable aperture diameter. The electrically controlled temperature-controlled shutter 9 has a cylindrical structure and is connected to the centrally-aperture cubic aperture 8 via a liquid transmission pipe. The surface temperature of the electrically controlled temperature-controlled shutter 9 is the same as the laboratory ambient temperature. The temperature measurement module measures the laboratory ambient temperature in real time and feeds it back to the constant-temperature liquid temperature controller so that the constant-temperature liquid temperature controller can adjust the circulating liquid temperature.

[0044] The electrically controlled rotating reflector 3 includes a gold-plated plane reflector, an electrically controlled rotating platform, and an electrically controlled stage controller. The gold-plated plane reflector is mounted on the electrically controlled rotating platform, and the electrically controlled stage controller controls the working state of the electrically controlled rotating platform. The electrically controlled rotating platform drives the gold-plated plane reflector to achieve optical path switching. The table size of the electrically controlled rotating platform is Ф100mm, the radial runout is less than 10μm, it rotates 360°, and the repeatability positioning accuracy is 0.05°, thus realizing the switching of the measurement optical path.

[0045] The sample heating furnace 4 uses electric heating to heat the graphite plate. The electrodes at both ends of the graphite plate are cooled by water. The sample to be tested is installed inside a fixed workpiece, which is supported by two graphite support rods placed parallel to each other in front of the graphite plate. Heating of the sample is achieved through radiative heat transfer. The sample heating furnace 4 is designed with a water-cooled jacket, and its interior is coated with a high-emissivity coating to reduce the influence of environmental radiation on the measurement results.

[0046] The main body of the 3D platform 5 is made of aluminum alloy and has been treated with black anodizing. The tabletop uses a standard hole spacing of 25mm×25mm and special fixing screw holes. The tabletop size is 500mm*500mm.

[0047] The optical collimation system 6 adopts a total reflection structure design, consisting of an aspherical mirror and a plane mirror. The effective radiation surfaces of the standard blackbody 1 and the sample under test are located at the focal point of the optical collimation system. The thermal radiation signals of the two are formed into a collimated beam after passing through the optical collimation system and are received by the Fourier transform infrared spectrometer.

[0048] The Fourier transform infrared spectrometer 7 uses the principle of interference to split the incident light, forming an interference phase distribution. The phase distribution is then received by the infrared detector under the convergence of the imaging mirror, and the spectral information can be recovered by Fourier transform.

[0049] A method for measuring the spectral emissivity of high-temperature materials using the above-mentioned device:

[0050] (1) Clamp the material sample on the sample heating furnace 4, insert the thermocouple thermometer into the side opening of the sample, install the sample heating furnace on the three-dimensional platform 5, turn on the built-in laser of the infrared Fourier transform spectrometer 7, so that the laser backlight path is incident on the surface of the material sample, adjust the three-dimensional platform 5 so that the laser point in the infrared Fourier transform spectrometer 7 is located at the center of the surface of the material sample, and complete the clamping and adjustment of the material sample.

[0051] (2) Turn on the standard blackbody 1, sample heating furnace 4, and electric rotating reflector 3 controller in sequence. Set the spectral range of the high-temperature material spectral emissivity measurement device to 1μm~15μm, the wavelength interval to 0.1μm, and the temperature measurement point T. Start the test after the standard blackbody 1 and the material sample temperature stabilize.

[0052] (3) Open the electronic shutter of the temperature-controlled aperture 2 at the front end of the standard blackbody 1, control the electronic rotating mirror 3 to rotate so that the radiation from the standard blackbody 1 enters the optical path, and read the output signal of the standard blackbody 1:

[0053] V i (λ, T) = K(λ){τ(λ)[ε B (λ,T)Lb (λ,T)+[1-ε B (λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )}

[0054] In the formula V i (λ, T) is the output signal of the standard blackbody 1, ε B (λ, T) is the standard blackbody spectral emissivity, L b (λ,T) represents the spectral radiance of a standard blackbody at wavelength λ and temperature T, where L b (λ,T a () represents wavelength λ and temperature T a Given the standard blackbody's spectral radiance, τ(λ) is the atmospheric transmittance, and K(λ) is the Fourier transform infrared spectrometer responsivity.

[0055] (4) Open the electronic shutter of the temperature control aperture 2 at the front end of the sample heating furnace 4, control the electronic rotating mirror 3 to rotate so that the infrared material sample radiation enters the optical path, and read the output signal of the material sample at the same temperature and wavelength as the standard blackbody 1:

[0056] V i ′(λ,T)=K(λ){τ(λ)[ε′ M (λ,T)L b (λ,T)+[1-ε′ M (λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )}

[0057] In the formula V i ε′(λ, T) is the output signal of the material sample, ε′ M (λ, T) represents the spectral emissivity of the material sample.

[0058] (5) Close the electric shutter 9 of the temperature control aperture 2 to make the temperature of the electrically controlled surface the same as the laboratory ambient temperature, and measure the background signal.

[0059] V0(λ,T)=K(λ){τ(λ)[ε0(λ,T)L b (λ,T a )+[1-ε0(λ,T)]L b (λ,T a )] +(1-τ(λ))L b (λ,T a )} =K(λ){τ(λ)Lb (λ,T a )+(1-τ(λ))L b (λ,T a )}

[0060] In the formula, V0(λ,T) is the background signal, and ε0(λ,T) is the spectral emissivity of the surface of the temperature-controlled aperture electronic shutter.

[0061] (6) By rearranging the above formula, we can calculate the spectral emissivity of the material sample using the definition of spectral emissivity:

[0062] V i ′(λ,T)-V0(λ,T)=K(λ)τ(λ)ε′ M (λ,T)[L b (λ,T)-L b (λ,T a )]

[0063] V i (λ,T)-V0(λ,T)=K(λ)τ(λ)ε B (λ,T)[L b (λ,T)-L b (λ,T a )]

[0064]

[0065] As can be seen from the above technical solutions, this invention uses a liquid-circulating temperature-controlled aperture, where the aperture surface temperature is the same as the laboratory ambient temperature. Therefore, when measuring spectral emissivity, there is no need to introduce a diffuse reflector with a reflectivity of approximately 1, nor is a vacuum constant temperature system required. This eliminates the influence of environmental radiation and atmospheric transmittance, thereby improving the accuracy of spectral emissivity measurement. Furthermore, this invention designs a gradient aperture to select the effective detection area of ​​the material sample, enabling high dynamic range measurement of infrared radiation signals over a wide temperature range.

[0066] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture, characterized in that, The measurement method employs a high-temperature material spectral emissivity measurement device based on a temperature-controlled aperture. The device includes: a standard blackbody (1), an electrically controlled rotating mirror (3), a sample heating furnace (4), a three-dimensional platform (5), an optical collimation system (6), and a Fourier transform infrared spectrometer (7). The standard blackbody (1) is arranged on one side of the electrically controlled rotating mirror (3), and the sample heating furnace (4) is arranged on the opposite side. The optical collimation system (6) is arranged on the reflecting side of the electrically controlled rotating mirror (3). The sample to be measured is arranged inside the sample heating furnace (4). The reflecting surfaces of the mirror (3) are switched sequentially, respectively converting the effective radiation surfaces of the standard blackbody (1) and the sample under test to the focal position of the optical collimation system (6). The thermal radiation signals of the standard blackbody (1) and the sample under test are collimated into a collimated beam after passing through the optical collimation system (6) and are received by the Fourier transform infrared spectrometer (7). The Fourier transform infrared spectrometer (7) uses the interference principle to perform interference and spectral dispersion on the incident light, forming an interference phase distribution. The phase distribution is received by the infrared detector under the convergence of the imaging mirror and the spectral information is restored after Fourier transform. The measuring device also includes There are two temperature control apertures: a first temperature control aperture (20) and a second temperature control aperture (21). The first temperature control aperture (20) is set at the thermal radiation outlet of the standard blackbody (1), and the second temperature control aperture (21) is set at the thermal radiation outlet of the sample heating furnace (4). The first temperature control aperture (20) and the second temperature control aperture (21) have the same structure, both including a constant temperature liquid temperature controller, a centrally opened cubic aperture (8), an electrically controlled temperature shutter (9), and a temperature measurement module. The constant temperature liquid temperature controller is connected to the centrally opened cubic aperture (8) through a liquid transmission pipe. The pipe interface (10) of 8) is connected, and the surface temperature of the aperture is controlled to be the same as the laboratory ambient temperature by using liquid circulation temperature control. The central aperture of the central aperture cube (8) is made of arc blades, and the aperture is continuously adjustable. The electric temperature control shutter (9) is a cylindrical structure and is connected to the central aperture cube (8) through a liquid transmission pipe. The surface temperature of the electric temperature control shutter (9) is the same as the laboratory ambient temperature. The temperature measurement module measures the laboratory ambient temperature in real time and feeds it back to the constant temperature liquid temperature controller so that the constant temperature liquid temperature controller can adjust the circulating liquid temperature. The measurement process is as follows: (1) The sample to be tested is clamped on the sample heating furnace (4), the thermocouple thermometer is inserted into the side opening of the sample, the sample heating furnace is installed on the three-dimensional platform (5), the built-in laser of the Fourier transform infrared spectrometer (7) is turned on, so that the laser backlight path is incident on the surface of the sample to be tested, and the three-dimensional platform (5) is adjusted so that the laser point in the Fourier transform infrared spectrometer (7) is located at the center of the material sample surface, and the material sample clamping adjustment is completed. (2) Turn on the controllers of the standard blackbody (1), sample heating furnace (4), and electrically controlled rotating reflector (3) in sequence. Set the spectral range of the high-temperature material spectral emissivity measurement device to 1μm~15μm, the wavelength interval to 0.1μm, and the temperature measurement point to 1μm. T The test will begin after the standard blackbody 1 and the material sample have reached stable temperatures. (3) Open the electronically controlled temperature-controlled shutter (9) of the front temperature-controlled aperture (2) of the standard blackbody (1), control the electronically controlled rotating mirror (3) to rotate so that the standard blackbody (1) radiates into the optical path, and read the output signal of the standard blackbody (1): In the formula This is the output signal of standard blackbody 1. Emissivity of a standard blackbody spectrum. For wavelength λ and temperature T Under the condition of standard blackbody spectral radiance, For wavelength λ and temperature T a Under the condition of standard blackbody spectral radiance, Atmospheric transmittance, For the Fourier transform infrared spectrometer responsivity; (4) Open the electrically controlled temperature control shutter (9) of the front temperature control aperture (2) of the sample heating furnace (4), control the electrically controlled rotating reflector (3) to rotate so that the infrared material sample radiation enters the optical path, and read the output signal of the material sample at the same temperature and wavelength as the standard blackbody (1): In the formula For the output signal of the material sample, The spectral emissivity of the material sample; (5) Close the electronically controlled temperature shutter (9) of the temperature control aperture (2) to make the temperature of the electronically controlled surface the same as the laboratory ambient temperature, and measure the background signal. In the formula For background signal, The surface spectral emissivity of the temperature-controlled aperture electronic shutter; (6) By rearranging the above formula, we can calculate the spectral emissivity of the material sample using the definition of spectral emissivity: 。 2. The method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture as described in claim 1, characterized in that, The standard blackbody (1) includes a graphite tube blackbody cavity, a temperature-controlled radiation thermometer, a temperature controller, and a power supply. The graphite tube blackbody cavity adopts the direct resistance heating principle based on graphite elements and is connected to water-cooled copper electrodes at both ends of the graphite ring. The power supply is used to heat the graphite tube. The graphite tube adopts an external conical structure. The graphite tube blackbody cavity is evacuated and filled with argon gas. Both ends of the graphite tube adopt an extended sealed cavity structure. Window flanges are installed on both sides of the extended sealed cavity, and quartz windows and KBr windows are installed respectively. The temperature-controlled radiation thermometer is a photoelectric pyrometer. During measurement, the optical imaging system at the front end of the photoelectric pyrometer is adjusted so that the photoelectric pyrometer focuses on the bottom of the blackbody cavity target to complete the measurement of the blackbody cavity temperature. The temperature controller adjusts the heating power of the power supply according to the set temperature value and the measurement value of the photoelectric pyrometer, and at the same time provides control operations for water cooling circulation and argon filling.

3. The method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture as described in claim 2, characterized in that, The electrically controlled rotating mirror (3) includes a gold-plated plane mirror, an electrically controlled rotating platform, and an electrically controlled moving stage controller. The gold-plated plane mirror is installed on the electrically controlled rotating platform, and the electrically controlled moving stage controller controls the working state of the electrically controlled rotating platform. The electrically controlled rotating platform drives the gold-plated plane mirror to achieve optical path switching.

4. The method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture as described in claim 3, characterized in that, The sample heating furnace (4) uses electric heating to heat the graphite plate. The electrodes at both ends of the graphite plate are cooled by water cooling. The sample to be tested is installed in a fixed workpiece, which is supported by two graphite support rods. The two graphite support rods are placed parallel to each other in front of the graphite plate, and the sample is heated by radiation heat transfer.

5. The method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture as described in claim 4, characterized in that, The sample heating furnace (4) has a water-cooled jacket and is coated with a high emissivity coating inside.

6. The method for measuring the spectral emissivity of high-temperature materials based on a temperature-controlled aperture as described in claim 5, characterized in that, The main material of the three-dimensional platform (5) is aluminum alloy, and it is subjected to black anodizing treatment; the optical collimation system (6) adopts a total reflection structure, which is composed of an aspherical mirror and a plane mirror.

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