Pulse uniform heating device for measuring thermal conductivity of thermal barrier coatings under high temperature conditions

Abstract

The present invention discloses a pulse uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high temperature conditions, which belongs to the field of thermal metrology technology. The present invention includes a pulse energy excitation system, an optical system and a sample holder system. The pulse excitation system includes a pulse laser and an optical fiber. The optical system includes a focusing lens, a focusing lens adjustment mechanism, a spot shape switcher, a first beam splitter, a first beam splitter adjustment frame, a second beam splitter, a second beam splitter adjustment frame, a detector, an energy meter and an optical cavity. An excitation optical path is used to adjust the laser spot according to the size and shape of the sample; by having an "inner petal" type sample holder, contact with the sample is further reduced, contact thermal resistance is reduced, and partial energy absorption by the sample holder is avoided, thereby improving the accuracy of thermal conductivity measurement; a variety of atmosphere interfaces are used to ensure the integrity, purity and emissivity of the sample, avoid oxidation and contamination of the sample, and can measure the thermal conductivity of thermal barrier coating samples under high temperature conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal metrology and relates to a pulse uniform heating device for measuring the thermal conductivity of a thermal barrier coating under high temperature conditions. Background Art

[0002] The primary development direction for today's aircraft engines is to increase turbine inlet temperatures, boost thrust-to-weight ratios, and enhance the thermal efficiency of turbine engine components, including those in harsh operating environments such as corrosion and oxidation. The surface temperature of a turbine blade with a thrust-to-weight ratio of 10 reaches 1100°C. The thermal conductivity of a thermal barrier coating directly affects its insulation performance and capacity, which in turn directly determines the cooling airflow rate. A thermal barrier coating with a thermal conductivity below 1.5 W / (m·K) effectively blocks heat transfer between the combustion gas and the base alloy, achieving insulation performance better than 80°C. This reduces cooling airflow by 15% and fuel consumption by approximately 0.4%, thereby simplifying the cold channel molding process and reducing blade processing costs. Therefore, accurately measuring thermal conductivity is a key technology for improving engine thrust-to-weight ratios, reducing fuel consumption, and extending turbine blade service life.

[0003] Current pulse heating devices for measuring the thermal conductivity of thermal barrier coatings using the laser flash method have three problems: First, they use only a single energy, single shape, and single size of laser energy to pulse heat the sample. This cannot meet the requirements for testing samples of multiple sizes or irregular shapes, and the quality of the laser energy cannot be monitored and corrected. This not only limits the range of TBC samples that can be measured, but also poses a significant risk to the accuracy of the measurement results. Second, a necessary condition for measuring the thermal conductivity of TBCs is that the front surface of the sample absorbs the pulse energy uniformly. If the front surface of the sample is not evenly illuminated by the laser or the sample holder absorbs some heat, an edge effect will occur, causing the temperature rise curve to continuously increase, making it impossible to complete the thermal conductivity measurement. Third, the current calculation of thermal conductivity based on the temperature rise curve only uses a mathematical algorithm to obtain the starting point of the temperature rise curve, which can introduce unpredictable errors and greatly affect the accuracy of the thermal conductivity measurement. Summary of the Invention

[0004] In response to the problems of existing pulse heating devices for measuring the thermal conductivity of thermal barrier coatings, such as a single laser energy form that cannot be monitored and corrected, the sample holder absorbing laser energy to form an edge effect, and the lack of a basis for the starting point of the temperature rise signal, the main purpose of the present invention is to provide a pulse uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high temperature conditions. The device adopts an excitation optical path to adjust the laser spot size and shape according to the sample size and shape, and can simultaneously analyze and correct the laser energy size, pulse width and spot quality. The "inner petal" type sample holder further reduces contact with the sample, reduces contact thermal resistance, avoids partial energy absorption by the sample holder, and improves the accuracy of thermal conductivity measurement. The device adopts multiple atmosphere interfaces to ensure the integrity, purity and emissivity of the sample, avoid sample oxidation and contamination, and can measure the thermal conductivity of thermal barrier coating samples under high temperature conditions.

[0005] The purpose of the present invention is achieved through the following technical solutions.

[0006] The present invention discloses a pulsed uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high-temperature conditions, comprising a pulsed energy excitation system, an optical system, and a sample holder system. The pulsed excitation system includes a pulsed laser and an optical fiber. The optical system comprises a focusing lens, a focusing lens adjustment mechanism, a spot shape switcher, a first beam splitter, a first beam splitter adjustment mount, a second beam splitter, a second beam splitter adjustment mount, a detector, an energy meter, and an optical cavity. The sample holding system comprises a vacuum transition chamber, a sample holder, and a sample. The sample holder base is threadedly secured to the bottom of the vacuum transition chamber; the sample is placed on the sample holder's sample seat.

[0007] The pulse laser excitation energy in the pulse excitation system ranges from 0 to 30 J, and the pulse width ranges from 0 to 10 ms.

[0008] The optical system comprises a focusing lens for receiving pulsed excitation energy transmitted by an optical fiber, and a focusing lens adjustment mechanism for adjusting the position and posture of the optical fiber head so that the laser is aimed at the target after being emitted. The pulsed laser energy concentrated by the focusing lens is converted into collimated light by a collimation adjustment lens group, and the collimated laser is adjusted to a collimated laser with the same shape and area as the sample by a spot shape switcher. The laser with adjusted shape and size enters the optical cavity, and 10% of the laser energy is reflected 90° by the first beam splitter to enter the energy meter, and 90% of the laser energy hits the center point of the second beam splitter. After passing through the second beam splitter, 90% of the laser energy is reflected 90°, changing from a horizontal direction to a vertical direction, passing through the inner tube of the sample holder, and accurately hitting the lower surface of the thermal barrier coating sample, thereby performing pulsed thermal excitation on the thermal barrier coating sample. 10% of the laser energy is horizontally transmitted to the photosensitive surface of the detector through the second beam splitter, serving as the starting time of the pulsed excitation.

[0009] In the sample fixing system, the sample holder base is fixed to the bottom of the vacuum transition chamber by means of threads; and the sample is placed on the sample seat of the sample holder.

[0010] Preferably, the focusing lens adjustment structure comprises, from top to bottom, a scissor lift, a dovetail guide manual translation stage, a manual rotation stage, a manual translation stage, and a focusing lens mounting bracket. These features include adjustment in five dimensions: up and down, left and right, front and back, pitch, and yaw, further ensuring that the laser energy accurately excites the back of the sample. The scissor lift has an adjustable height of 60 to 120 mm, ensuring that the focusing lens and the reflector within the optical vacuum chamber are at the same level. The dovetail guide manual translation stage allows for rapid adjustment of the focusing lens's forward and backward displacement. The manual rotation stage adjusts the focusing lens's horizontal angle. The manual translation stage allows for fine-tuning of the focusing lens's horizontal position, front and back, left and right. The focusing lens mounting bracket secures the focusing lens horizontally to the manual translation stage.

[0011] Preferably, the first and second beam splitter mounting brackets have three-dimensional directional adjustment capabilities and are mechanically fixed to the first and second 45° brackets, respectively, with screws. The first beam splitter is fixed to the first beam splitter mounting bracket and further reflects 10% of the laser energy at a 90-degree angle into an energy meter. The energy meter measures the energy generated by sample heating and calculates the laser energy absorbed by the sample based on the sample emissivity. The remaining 90% of the energy is directed horizontally to the center of the second beam splitter. The second beam splitter is fixed to the second beam splitter mounting bracket and further reflects 90% of the laser energy directed horizontally to the center of the second beam splitter, converting the horizontal direction into a vertical direction. The energy is then directed vertically through the inner tube of the sample holder and accurately onto the lower surface of the thermal barrier coating sample, providing pulsed thermal excitation of the thermal barrier coating sample. The remaining 10% of the laser energy is directed horizontally to the detector's photosensor, serving as the starting point for the pulse excitation. The detector is fixed to a reserved hole on a manual translation stage. The manual translation stage has two-dimensional angle adjustment, allowing the detector's position to be adjusted vertically and horizontally, ensuring that the laser energy fully reaches the detector's photosensor. The mounting bracket bears the weight of all the above components.

[0012] Preferably, the sample holder has an "inner petal" structure to further reduce contact with the sample, reduce contact thermal resistance, and improve the accuracy of thermal conductivity measurement.

[0013] The pulsed uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high-temperature conditions disclosed in the present invention operates as follows: to ensure the integrity, purity, and emissivity of the sample and to prevent oxidation and contamination of the sample, an inert gas is introduced through an atmosphere interface to achieve pressure equilibrium. Laser energy emitted by a pulsed laser is then guided through an optical fiber and processed by a focusing lens, a collimating adjustment lens assembly, and a spot shape switcher to form a laser spot with the same shape and size as the sample. 10% of the laser energy is reflected 90 degrees by a first beam splitter and enters an energy meter for analysis and correction of the laser energy, pulse width, and spot quality. 90% of the laser energy is directed to the center point of a second beam splitter. After passing through the second beam splitter, 90% of the laser energy is reflected 90 degrees, changing from a horizontal direction to a vertical direction. The laser energy passes through the inner tube of the sample holder and accurately strikes the lower surface of the thermal barrier coating sample placed on an "inner petal" sample holder, thereby pulse-exciting the thermal barrier coating sample. 10% of the laser energy is horizontally transmitted through the second beam splitter to the photosensitive surface of the detector, serving as the starting point of the pulse excitation time for calculating the thermal conductivity. The thermal conductivity is calculated by the following thermal conductivity calculation formula, which realizes the thermal conductivity measurement of the thermal barrier coating.

[0014] Thermal conductivity calculation formula:

[0015] λ=α·c p ·ρ

[0016] λ—thermal conductivity, in watts per meter Kelvin [W / (m·K)];

[0017] α—thermal diffusion coefficient, unit is square meter per second (m 2 / s);

[0018] c p —Specific heat capacity, expressed in joules per kilogram Kelvin [J / (kg·K)];

[0019] ρ—bulk density, in kilograms per cubic meter (kg / m 3 )

[0020] The bulk density is determined according to the corresponding standards, and the specific heat capacity can be obtained by looking up relevant information.

[0021] Thermal diffusivity calculation formula:

[0022] α=0.13879L 2 / t 1 / 2

[0023] t 1 / 2 =t1-t0

[0024] L—sample thickness, in m;

[0025] t1—the time corresponding to half of the maximum temperature rise, in seconds;

[0026] t0—Starting point of pulse excitation time, in seconds.

[0027] Beneficial effects:

[0028] 1. The pulse uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high-temperature conditions disclosed in the present invention adopts an excitation optical path to adjust the laser spot size and shape according to the sample size and shape. At the same time, the quality of the laser, such as energy, pulse width, and spot quality, can be analyzed and corrected to ensure that the front surface of the sample accurately and uniformly absorbs the pulse energy.

[0029] 2. The pulse uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high temperature conditions disclosed in the present invention adopts a sample holder with an "inner petal" structure to further reduce contact with the sample, reduce contact thermal resistance, and avoid the sample holder absorbing part of the energy, which has a positive effect on improving the accuracy of thermal conductivity measurement.

[0030] 3. The pulse uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high temperature conditions disclosed in the present invention adopts multiple atmosphere interfaces to ensure the integrity, purity and emissivity of the sample, avoid oxidation and contamination of the sample, and can measure the thermal conductivity of thermal barrier coating samples under high temperature conditions.

[0031] 4. The pulse uniform heating device disclosed in the present invention for measuring the thermal conductivity of thermal barrier coatings under high temperature conditions performs pulse excitation on the thermal barrier coating sample. 10% of the laser energy is horizontally transmitted to the photosensitive surface of the detector through the second beam splitter, which serves as the starting point of the pulse excitation time for calculating the thermal conductivity. This provides a basis for the starting point of the temperature rise signal and improves the measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a composition diagram of a pulse uniform heating device for measuring the thermal conductivity of a thermal barrier coating under high temperature conditions according to the present invention.

[0033] Figure 2 This is a diagram of the focusing lens adjustment structure.

[0034] Figure 3 This is a diagram of the beam splitter system.

[0035] Figure 4 Diagram of the sample fixing system.

[0036] Among them: 1- pulse laser, 2- optical fiber, 3- focusing lens, 4- focusing lens adjustment mechanism, 4.1- focusing lens fixing frame, 4.2- manual translation stage, 4.3- manual rotation stage, 4.4- dovetail guide manual translation stage, 4.5- scissor lift, 5- laser, 6- collimation adjustment lens group, 7- spot shape switcher, 8- first beam splitter, 9- first beam splitter adjustment frame, 9.1- manual translation stage 1, 9.2- first 45° bracket, 9.3- first beam splitter fixing frame, 10- second beam splitter, 11- second beam splitter adjustment frame, 11.1- manual translation stage 2, 11.2- second 45° bracket, 11.3- second beam splitter fixing frame, 12- detection system, 12.1- fixed bracket, 12.2- manual translation stage 3 12.3-Detector, 13-Energy meter, 14-Optical cavity, 15-Atmosphere interface, 16-Optical window, 17-Vacuum transition chamber, 18-Sample holder, 19-Thermal barrier coating sample. DETAILED DESCRIPTION

[0037] The present invention is described in detail below with reference to the accompanying drawings.

[0038] like Figure 1 As shown, the pulsed uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high-temperature conditions disclosed in this embodiment includes a pulsed energy excitation system, an optical system, and a sample support system. The pulsed energy excitation system is located in front of the optical system and is primarily used to generate uniform pulsed excitation energy. The optical system is located below the sample support system and is isolated from the sample support system by an optical window 16. It is primarily used to accurately direct the excitation energy generated by the laser to the back of the thermal barrier coating sample, generating a high signal-to-noise ratio temperature rise signal. It also has the functions of energy measurement and temperature rise signal start time measurement. The sample fixation system is primarily used to fix the sample and has a minimum contact area with the sample.

[0039] The pulse energy excitation system includes a pulse laser 1 and an optical fiber 2. Laser light 5 is emitted by the pulse laser 1 and is led to the optical system through the optical fiber 2. The excitation energy of the pulse laser 1 ranges from 0 to 30 J, and the pulse width of the pulse laser 1 ranges from 0 to 10 ms.

[0040] The optical system includes a focusing lens 3, a focusing lens adjustment mechanism 4, a spot shape switcher 7, a first beam splitter 8, a first beam splitter adjustment frame 9, a second beam splitter 10, a second first beam splitter adjustment frame 1, a detector 12, an energy meter 13 and an optical cavity 14. The focusing lens 3 receives the pulse excitation energy transmitted by the optical fiber, and the focusing lens adjustment mechanism 4 can adjust the position and posture of the optical fiber head so that the laser is aimed at the target after being emitted; the pulse laser energy concentrated by the focusing lens 3 enters the collimation adjustment lens group 6 to become collimated light, and the collimated laser is adjusted to a collimated laser with the same shape and area as the sample through the spot shape switcher 7; the laser with adjusted shape and size enters the optical cavity 14, and after passing through the first beam splitter 8, 10% of the laser energy is reflected 90° and enters the energy meter 13, and 90% of the laser energy hits the center point of the second beam splitter 10; after passing through the second beam splitter 10, 90% of the laser energy is reflected 90°, from horizontal direction to vertical direction, passes through the inner tube of the sample holder 18, and accurately hits the lower surface of the thermal barrier coating sample, performing pulse thermal excitation on the thermal barrier coating sample; and 10% of the laser energy is horizontally transmitted through the second beam splitter 10 to the photosensitive surface of the detector system 12, which serves as the starting time of the pulse excitation.

[0041] The sample fixing system includes a vacuum transition chamber 17, a sample holder 18 and a sample 19. The base of the sample holder 18 is fixed to the bottom of the vacuum transition chamber 17 by screw threads; the sample 19 is placed on the sample seat of the sample holder 18.

[0042] like Figure 2 The focusing lens adjustment structure, from top to bottom, consists of a scissor lift platform 4.1, a dovetail guide manual translation platform 4.2, a manual rotation platform 4.3, a manual translation platform 4.4, and a focusing lens mounting bracket 4.5. These features five dimensions of adjustment: vertical, horizontal, forward, backward, pitch, and yaw, further ensuring accurate laser energy excitation of the backside of the sample. The scissor lift platform 1 can be adjusted from 60 to 120 mm in height, aligning the focusing lens with the reflector within the optical vacuum chamber. The dovetail guide manual translation platform 4.2 allows for rapid adjustment of the focusing lens's forward and backward displacement. The manual rotation platform 4.3 adjusts the focusing lens's horizontal angle. The manual translation platform 4.4 allows for fine-tuning of the focusing lens's horizontal position, front to back, and left to right. The focusing lens mounting bracket 4.5 secures the focusing lens horizontally to the manual translation platform.

[0043] like Figure 3The beam splitter system includes a first manual translation stage 9.1, a first 45° bracket 9.2, a first beam splitter fixing frame 9.3, a first beam splitter 8, a second manual translation stage 11.1, a second 45° bracket 11.2, a second beam splitter fixing frame 11.3, a second beam splitter 10, a fixing bracket 12.1, a third manual translation stage 12.2 and a detector 12.3. The first 45° bracket 9.2 and the second 45° bracket 11.2 are mechanically fixed to the first manual translation stage 9.1 and the second manual translation stage 11.1 respectively with screws; the first beam splitter fixing frame 9.3 and the second beam splitter fixing frame 11.3 have a three-dimensional direction adjustment function and are mechanically fixed to the first 45° bracket 9.2 and the second 45° bracket 11.2 respectively with screws; the first beam splitter 8 is fixed to the first beam splitter fixing frame 9.3, and further 10% of the laser energy is reflected at 90° and placed in the energy meter 13. The energy meter 13 can measure the energy of the sample heated, and the laser energy absorbed by the sample can be further calculated in combination with the sample emissivity. The remaining 90% of the energy level enters the second beam splitter The center of the second beam splitter 8 is located at the center of the second beam splitter 8. The second beam splitter 8 is fixed to the second beam splitter fixing bracket 11.3, further reflecting 90% of the laser energy hitting the center point of the second beam splitter 8 from the horizontal direction to the vertical direction, passing through the inner tube of the sample holder 18 and accurately hitting the lower surface of the thermal barrier coating sample, thereby pulsed thermal excitation of the thermal barrier coating sample. The remaining 10% of the laser energy is horizontally hit on the photosensitive surface of the detector 12.3, which serves as the starting point of the pulse excitation. The detector 12.3 is fixed to the reserved hole of the third manual translation stage 12.2. The third manual translation stage 12.2 has a two-dimensional adjustment angle, which can adjust the position of the detector 12.3 up and down and left and right to ensure that the laser energy fully reaches the photosensitive surface of the detector 12.3. The fixing bracket 12.1 bears the weight of all the above components.

[0044] like Figure 4 The sample holding system comprises a base 18.1, a connecting tube 18.2, a sample holder 18.3, and a fastening cap 18.4. The connecting tube 18.2 is threadedly fixed to the base 18.1. Its hollow structure further reduces heat loss from the holder, minimizing heating of the entire holder. The sample holder 18.3 is threadedly fixed above the connecting tube 18.2. Its "inner petal" structure further minimizes contact with the sample, reducing contact thermal resistance and positively impacting thermal conductivity measurement accuracy.

[0045] The pulsed uniform heating device for measuring the thermal conductivity of thermal barrier coatings under high-temperature conditions disclosed in this embodiment operates as follows: To ensure sample integrity, purity, and emissivity and prevent sample oxidation and contamination, an inert gas is introduced through the atmosphere port to achieve pressure equilibrium. Laser energy emitted by a pulsed laser is then guided through an optical fiber and processed by a focusing lens, a collimation adjustment lens assembly, and a spot shape switcher to form a laser spot with the same shape and size as the sample. A first beam splitter reflects 10% of the laser energy 90 degrees and enters an energy meter for analysis and correction of the laser energy, pulse width, and spot quality. 90% of the laser energy is directed to the center point of a second beam splitter. After passing through the second beam splitter, 90% of the laser energy is reflected 90 degrees, changing from horizontal to vertical, and passes through the inner tube of the sample holder to accurately strike the lower surface of the thermal barrier coating sample placed on an "inner petal" sample holder, providing pulse excitation for the thermal barrier coating sample. 10% of the laser energy is horizontally transmitted through the second beam splitter to the photosensitive surface of the detector, serving as the starting point of the pulse excitation time for thermal conductivity calculation. The thermal conductivity is calculated by the following thermal conductivity calculation formula, which realizes the thermal conductivity measurement of the thermal barrier coating.

[0046] Thermal conductivity calculation formula:

[0047] λ=α·c p ·ρ

[0048] λ—thermal conductivity, in watts per meter Kelvin [W / (m·K)];

[0049] α—thermal diffusion coefficient, unit is square meter per second (m 2 / s);

[0050] c p —Specific heat capacity, expressed in joules per kilogram Kelvin [J / (kg·K)];

[0051] ρ—bulk density, in kilograms per cubic meter (kg / m 3 )

[0052] Wherein the thermal diffusion coefficient is obtained by solving the present embodiment, the bulk density is measured according to the corresponding standard, and the specific heat capacity can be obtained by searching relevant data.

[0053] Thermal diffusivity calculation formula:

[0054] α=0.13879L 2 / t 1 / 2

[0055] t 1 / 2 =t1-t0

[0056] L—sample thickness, in m;

[0057] t1—the time corresponding to half of the maximum temperature rise, in seconds;

[0058] t0—Starting point of pulse excitation time, in seconds.

[0059] The above specific description further illustrates the purpose, technical solutions and beneficial effects of the invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A pulse uniform heating device for measuring thermal conductivity of thermal barrier coatings under high temperature conditions, characterized by: The invention comprises a pulse energy excitation system, an optical system and a sample holder system; the pulse energy excitation system comprises a pulse laser and an optical fiber; the optical system comprises a focusing lens, a focusing lens adjustment mechanism, a spot shape switcher, a first beam splitter, a first beam splitter adjustment frame, a second beam splitter, a second beam splitter adjustment frame, a detector, an energy meter and an optical cavity; the sample holder system comprises a vacuum transition chamber, a sample holder and a sample; the sample holder base is fixed to the bottom of the vacuum transition chamber by a threaded manner; the sample is placed on the sample seat of the sample holder; The pulse laser excitation energy in the pulse energy excitation system covers 0 to 30 J, and the pulse width covers 0 to 10 ms; In the optical system, the focusing lens is used to receive the pulse excitation energy transmitted by the optical fiber, and the focusing lens adjustment mechanism is used to adjust the position and posture of the optical fiber head so that the laser is aimed at the target after being emitted; The pulsed laser energy gathered by the focusing lens is converted into collimated light by the collimating adjustment lens group. The collimated laser is adjusted to a collimated laser with the same shape and area as the sample through the spot shape switcher. The laser with adjusted shape and size enters the optical cavity. After passing through the first beam splitter, 10% of the laser energy is reflected 90° and enters the energy meter, and 90% of the laser energy hits the center point of the second beam splitter. After passing through the second beam splitter, 90% of the laser energy is reflected 90°, changing from horizontal direction to vertical direction, passing through the inner tube of the sample holder, and accurately hitting the lower surface of the thermal barrier coating sample, thereby performing pulsed thermal excitation on the thermal barrier coating sample. 10% of the laser energy is horizontally transmitted to the photosensitive surface of the detector through the second beam splitter, which serves as the starting point of the pulse excitation. In the sample fixing system, the base of the sample holder is fixed to the bottom of the vacuum transition chamber by means of threads; the sample is placed on the sample seat of the sample holder; The focusing lens adjustment structure is composed of a scissor lift, a dovetail guide manual translation stage, a manual rotation stage, a manual translation stage, and a focusing lens fixing frame from top to bottom. It has adjustment functions in five dimensions: up and down, left and right, front and back, pitch, and yaw, further ensuring that the laser energy accurately stimulates the back of the sample; the scissor lift can adjust the height of 60 to 120 mm, so that the focusing lens and the reflector in the optical vacuum chamber are at the same level; the dovetail guide manual translation stage is used to quickly adjust the front and back displacement of the focusing lens; the manual rotation stage is used to adjust the horizontal angle of the focusing lens; the manual translation stage is used to finely adjust the horizontal position of the focusing lens front and back, left and right; the focusing lens fixing frame fixes the focusing lens horizontally on the manual translation stage; The first and second beam splitter mounting brackets feature three-dimensional adjustment and are mechanically fixed to the first and second 45° brackets, respectively, with screws. The first beam splitter, mounted on the first beam splitter mounting bracket, further reflects 10% of the laser energy at a 90-degree angle into an energy meter. The energy meter measures the energy generated by sample heating and calculates the laser energy absorbed by the sample based on the sample's emissivity. The remaining 90% of the energy is directed horizontally to the center of the second beam splitter. The second beam splitter, mounted on the second beam splitter mounting bracket, further reflects 90% of the laser energy directed horizontally to the center of the second beam splitter, passing through the inner tube of the sample holder and accurately striking the lower surface of the thermal barrier coating sample for pulsed thermal excitation. The remaining 10% of the laser energy is directed horizontally to the detector's photosensor, serving as the starting point for the pulse excitation. The detector is mounted on a reserved hole in a manual translation stage. The manual translation stage features two-dimensional adjustment for adjusting the detector's position vertically and horizontally, ensuring that the laser energy fully reaches the detector's photosensor. The mounting bracket bears the weight of all the above components.

2. The pulse uniform heating device for measuring thermal conductivity of thermal barrier coatings under high temperature conditions according to claim 1, characterized in that: The sample holder has an "inner petal" structure, which further reduces contact with the sample, reduces contact thermal resistance, and improves the accuracy of thermal conductivity measurement.

3. The pulse uniform heating device for measuring thermal conductivity of thermal barrier coatings under high temperature conditions according to claim 1 or 2, characterized in that: To ensure sample integrity, purity, and emissivity and avoid sample oxidation and contamination, an inert gas is introduced through the atmosphere port to achieve pressure equilibrium. The pulsed laser's laser energy is then directed through an optical fiber and processed by a focusing lens, collimating lens assembly, and spot shape switcher to form a laser spot with the same shape and size as the sample. The first beam splitter reflects 10% of the laser energy 90 degrees and directs it into an energy meter for analysis and correction of laser energy, pulse width, and spot quality. The remaining 90% of the laser energy is directed to the center of the second beam splitter. After passing through the second beam splitter, 90% of the laser energy is reflected 90 degrees, changing from horizontal to vertical, passing through the inner tube of the sample holder and accurately striking the lower surface of the thermal barrier coating sample placed on the "inner petal" sample holder, providing pulse excitation for the thermal barrier coating sample. 10% of the laser energy is transmitted horizontally through the second beam splitter to the detector's photosensitive surface, serving as the pulse excitation time starting point for thermal conductivity calculation. The thermal conductivity is then measured using the following formula: Thermal conductivity calculation formula: λ=α·c p ·r λ—thermal conductivity, in watts per meter Kelvin [W / (m·K)]; α—thermal diffusion coefficient, unit is square meter per second (m 2 / s); c p —Specific heat capacity, expressed in joules per kilogram Kelvin [J / (kg·K)]; ρ — Bulk density, in kilograms per cubic meter (kg / m 3 ) The bulk density is determined according to the corresponding standards, and the specific heat capacity is obtained by searching relevant data; Thermal diffusivity calculation formula: α=0.13879L 2 / t 1 / 2 t 12 =t1-t0 L—sample thickness, in m; t1—the time corresponding to half of the maximum temperature rise, in seconds; t0—Starting point of pulse excitation time, in seconds.

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