Method for calibrating irradiation crystal at multiple temperature points

Abstract

The present application relates to the technical field of aero-engine testing, and discloses a method for calibrating a radiation crystal at multiple temperature points, comprising the following steps: S10: heating a tube furnace and controlling the core temperature of the tube furnace; S20: determining the temperature gradient in the tube furnace, and determining the setting coordinates of the radiation crystal according to the temperature gradient; S30: setting the radiation crystal on a test sample, and placing the test sample in the tube furnace for heating; S40: after the heating process is completed, taking the radiation crystal from the test sample, analyzing and processing the radiation crystal, and obtaining the recovery rate of radiation defects; and S50: obtaining the calibration curve of the radiation crystal according to the recovery rate of radiation defects. The present application determines the temperature gradient in the tube furnace to obtain the setting coordinates of the radiation crystal, and realizes the calibration of the radiation crystal at multiple temperature points through one heating process by using different temperature gradients in the tube furnace, thereby shortening the test period of the temperature test of the same batch of radiation crystals and improving the calibration efficiency of the radiation crystal.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engine testing, and particularly relates to a method for calibrating irradiation crystals at multiple temperature points. BACKGROUND

[0002] The irradiation crystal temperature measurement technology is a temperature measurement technology of irradiation defects which has arisen in the field of aero-engine testing in recent years. Before the irradiation crystal temperature measurement test is performed, the irradiation crystals of the same batch need to be calibrated at temperature. The temperature calibration needs to select multiple temperature points for high-temperature annealing in a certain temperature range.

[0003] In the prior art, only one temperature point can be calibrated in each heating process during the calibration of the irradiation crystals. Therefore, the calibration of the irradiation crystals of the same batch needs to be repeatedly performed in the heating and annealing processes, and the test cycle of the irradiation crystal temperature measurement test is relatively long. SUMMARY

[0004] Therefore, the present application provides a method for calibrating irradiation crystals at multiple temperature points to solve the problem of a long test cycle of the calibration of the irradiation crystals of the same batch.

[0005] In a first aspect, the present application provides a method for calibrating irradiation crystals at multiple temperature points, comprising the following steps:

[0006] Step S10: heating a tube furnace and controlling the core temperature of the tube furnace;

[0007] Step S20: determining the temperature gradient in the tube furnace, and determining the setting coordinates of the irradiation crystals on a test sample according to the temperature gradient in the tube furnace;

[0008] Step S30: setting the irradiation crystals on the test sample and placing the test sample in the tube furnace for heating;

[0009] Step S40: taking out the irradiation crystals from the test sample after the heating process is completed, analyzing and processing the irradiation crystals, and obtaining the recovery rate of irradiation defects;

[0010] Step S50: obtaining the calibration curve of the irradiation crystals according to the recovery rate of irradiation defects.

[0011] Beneficial effects: The setting coordinates of the irradiation crystals are obtained by determining the temperature gradient in the tube furnace, the calibration of the irradiation crystals at multiple temperature points is completed by using the different temperature gradients in the tube furnace in one heating process, the test cycle of the irradiation crystal temperature measurement test of the same batch is shortened, and the calibration efficiency of the irradiation crystals is improved.

[0012] In an optional embodiment, in step S20, the method for determining the temperature gradient inside the tube furnace and the setting coordinates of the irradiated crystal on the test sample includes the following steps:

[0013] Step S21: Obtain the basic furnace temperature gradient of the tubular furnace through a paint temperature measurement test;

[0014] Step S22: Based on the temperature gradient inside the basic furnace and the temperature calibrated by the irradiated crystal, obtain the basic coordinate parameters, and set multiple thermocouples on the temperature measuring sample according to the basic coordinate parameters;

[0015] Step S23: Place the temperature measuring sample in a tube furnace for heating treatment to obtain basic temperature parameters;

[0016] Step S24: Based on the basic coordinate parameters and the basic temperature parameters, obtain the basic fitting curve using the fitting formula;

[0017] Step S25: Based on the basic fitting curve and the temperature calibrated by the irradiated crystal, obtain the corrected coordinate parameters of the thermocouple. Based on the corrected coordinate parameters, adjust the position of the thermocouple on the temperature measuring sample. Then, place the temperature measuring sample in a tube furnace for heating treatment to obtain the corrected temperature parameters.

[0018] Step S26: Based on the corrected coordinate parameters and the corrected temperature parameters, obtain the corrected fitting curve using the fitting formula;

[0019] Step S27: Calculate the difference between the base fitting curve and the modified fitting curve using the error formula. When the difference calculation result is greater than the standard error value δ0, take the modified fitting curve as the base fitting curve and repeat step S24; when the difference calculation result is less than the standard error value δ0, proceed to step S28.

[0020] Step S28: Determine the temperature gradient of the tube furnace by correcting the fitted curve, and determine the setting coordinates of the irradiated crystal by correcting the coordinate parameters.

[0021] Beneficial effects: By iteratively correcting the fitted curves of temperature and coordinate parameters, a high-precision furnace temperature gradient is obtained, and the setting coordinates of the irradiated crystal at the calibration temperature are determined by the high-precision furnace temperature gradient, thereby improving the accuracy of multi-temperature point calibration of the irradiated crystal.

[0022] In one optional implementation, the fitting formula is: y = a1x k-1 +a2x k-2 +……a k Where y is temperature, x is distance, and a1 to a k are the coefficients of the polynomial.

[0023] In an optional embodiment, the error formula is: |y n -y n-1 |=δ, wherein y n is the modified fitting curve, y n-1 is the basic fitting curve, and δ is the difference between the basic fitting curve and the modified fitting curve.

[0024] In an optional embodiment, in the step S23, the method for obtaining the basic temperature parameter is: by setting a signal acquisition module, connecting the signal acquisition module with the thermocouple to collect the electrical signal output by the thermocouple, and converting the electrical signal into a digital signal output to a computer, and obtaining the basic temperature parameter through the calculation of the computer.

[0025] In an optional embodiment, the precision of the thermocouple is δ1, the precision of the signal acquisition module is δ2, and the standard error value

[0026] In an optional embodiment, the distance between two adjacent thermocouples is L, and L≥15mm is satisfied.

[0027] Beneficial effect: by limiting the distance between two adjacent thermocouples, the mutual interference between the thermocouples is prevented, and the accuracy of the measurement result is ensured.

[0028] In an optional embodiment, in the step S30, the heating method of the test sample includes the following steps:

[0029] Step S31: first pre-heating the test sample;

[0030] Step S32: then stably heating the test sample;

[0031] Step S33: finally cooling the test sample.

[0032] Beneficial effect: by using the heating method of pre-heating first, then stable heating, and finally cooling, the test cycle process of the aero-engine from the slow state to the maximum flight state and then to the mantle state is simulated, and the test process of the irradiation crystal in the engine temperature test is simulated.

[0033] In an optional embodiment, the pre-heating time of the test sample is 10 minutes, the stable heating time of the test sample is 5 minutes, and the cooling time of the test sample is 10 minutes.

[0034] In an alternative embodiment, in the step S40, the irradiated crystal is analyzed and processed to obtain the irradiation defect recovery rate, and the method comprises the following steps:

[0035] Step S41: using an X-ray diffractometer to perform crystal interpretation on the irradiated crystal to obtain a diffraction pattern;

[0036] Step S42: analyzing and processing the diffraction pattern by a computer to obtain a diffraction peak half-height width and a lattice constant;

[0037] Step S43: converting the diffraction peak half-height width and the lattice constant into an irradiation defect recovery rate. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0039] Figure 1 The flowchart of the irradiated crystal multi-temperature point calibration method of the embodiment of the present application;

[0040] Figure 2 The flowchart of the method for determining the temperature gradient in the tube furnace and the setting coordinates of the irradiated crystal on the test sample of the embodiment of the present application;

[0041] Figure 3 The flowchart of the heating method of the test sample of the embodiment of the present application;

[0042] Figure 4 The flowchart of the method for analyzing and processing the irradiated crystal to obtain the irradiation defect recovery rate of the embodiment of the present application;

[0043] Figure 5 The structural diagram of the tube furnace and the test sample of the embodiment of the present application;

[0044] Figure 6 The electrical connection diagram of the thermocouple, the signal acquisition module and the computer of the embodiment of the present application.

[0045] Explanation of reference signs:

[0046] 10, tube furnace; 20, test sample; 21, mounting hole; 30, temperature measuring sample; 40, thermocouple; 50, signal acquisition module; 60, computer. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The following is combined with Figures 1 to 6 The following describes embodiments of the present invention.

[0049] According to an embodiment of the present invention, in one aspect, a method for multi-temperature point calibration of an irradiated crystal is provided, comprising the following steps:

[0050] Step S10: Heat the tube furnace 10 and control the core temperature of the tube furnace 10;

[0051] Step S20: Determine the temperature gradient inside the tube furnace 10, and determine the setting coordinates of the irradiated crystal on the test sample 20 based on the temperature gradient inside the furnace.

[0052] Step S30: Place the irradiated crystal on the test sample 20, and place the test sample 20 in the tube furnace 10 for heating;

[0053] Step S40: After the heating process is completed, the irradiated crystal is removed from the test sample 20, and the irradiated crystal is analyzed to obtain the irradiation defect recovery rate;

[0054] Step S50: Obtain the calibration curve of the irradiated crystal based on the irradiation defect recovery rate.

[0055] By applying the multi-temperature point calibration method for irradiated crystals in this embodiment, the set coordinates of the irradiated crystals are obtained by determining the temperature gradient inside the tube furnace 10. The calibration of multiple temperature points of the irradiated crystals is completed in one heating process by utilizing the different temperature gradients inside the tube furnace 10, which shortens the test cycle of temperature measurement tests for the same batch of irradiated crystals and improves the calibration efficiency of irradiated crystals.

[0056] Specifically, in this embodiment, the material of the test sample 20 is GH3128.

[0057] Of course, in other alternative embodiments, the material of the test sample 20 can also be other high-temperature resistant materials, such as titanium alloys.

[0058] Specifically, such as Figure 5 As shown, according to the setting coordinates of the irradiated crystal determined in step S20, a number of mounting holes 21 are opened on the test sample 20 to facilitate the placement of the irradiated crystal on the test sample 20.

[0059] It should be noted that when the core temperature of the tube furnace 10 is the same, the temperature gradient in a specific area of the tube furnace 10 has high repeatability, and by using this characteristic, the purpose of one-time heating of the tube furnace 10 and multi-temperature point heating of the irradiation crystal in the same batch is achieved, and the calibration curve of the irradiation crystal is obtained.

[0060] In one embodiment, as shown in FIG. 1, the method for determining the temperature gradient in the tube furnace 10 and the setting coordinates of the irradiation crystal on the test sample 20 includes the following steps: Figure 2

[0061] Step S21: Obtain the basic temperature gradient in the tube furnace 10 through a temperature paint temperature test;

[0062] Step S22: Obtain the basic coordinate parameters according to the basic temperature gradient in the tube furnace and the calibrated temperature of the irradiation crystal, and set multiple thermocouples 40 on the temperature measurement sample 30 according to the basic coordinate parameters;

[0063] Step S23: Place the temperature measurement sample 30 in the tube furnace 10 for heating treatment to obtain the basic temperature parameters;

[0064] Step S24: Obtain the basic fitting curve through a fitting formula according to the basic coordinate parameters and the basic temperature parameters;

[0065] Step S25: Obtain the corrected coordinate parameters of the thermocouples 40 according to the basic fitting curve and the calibrated temperature of the irradiation crystal, adjust the positions of the thermocouples 40 on the temperature measurement sample 30 according to the corrected coordinate parameters, and then place the temperature measurement sample 30 in the tube furnace 10 for heating treatment to obtain the corrected temperature parameters;

[0066] Step S26: Obtain the corrected fitting curve through a fitting formula according to the corrected coordinate parameters and the corrected temperature parameters;

[0067] Step S27: Calculate the difference between the basic fitting curve and the corrected fitting curve through an error formula, when the difference calculation result is greater than the standard error value δ0, the corrected fitting curve at this time is taken as the basic fitting curve, and step S24 is performed again; when the difference calculation result is less than the standard error value δ0, step S28 is performed;

[0068] Step S28: Determine the temperature gradient of the tube furnace 10 through the corrected fitting curve, and determine the setting coordinates of the irradiation crystal through the corrected coordinate parameters.

[0069] It should be noted that by iteratively correcting the fitting curve of the temperature and coordinate parameters, a high-precision temperature gradient in the furnace is obtained, and the setting coordinates of the irradiation crystal at the calibration temperature are determined through the high-precision temperature gradient in the furnace, thereby improving the accuracy of the multi-temperature point calibration of the irradiation crystal. ​

[0070] Specifically, the principle of the temperature test of the temperature indicating paint is based on the color change of the color indicator in the material composition of the temperature indicating paint with the temperature change. The color indicator is the main component of the temperature indicating paint for temperature sensing and color change, which can change color in a specific temperature range, thereby reflecting the temperature of the measured object.

[0071] It should be noted that the test result obtained by the temperature test of the temperature indicating paint has low accuracy, which is difficult to meet the demand of the temperature curve calibration of the irradiation crystal, and therefore the temperature gradient of the tube furnace 10 needs to be obtained by parameter correction.

[0072] It should be noted that the temperature gradient exists from the core to the edge, and the temperature is continuous. Therefore, the irradiation crystal is calibrated according to the temperature section, and the temperature section for calibration is the temperature value fed back by the first thermocouple 40 and the last thermocouple 40 on the test sample 20.

[0073] Preferably, in order to ensure the accuracy of the test result, the material and size of the temperature measuring sample 30 are consistent with those of the test sample 20, and it can be understood that the test sample 20 can be directly used as the temperature measuring sample 30 for testing.

[0074] In an embodiment, the fitting formula is: y=a1x k-1 +a2x k-2 +…a k , wherein y is the temperature, x is the distance, a1 to a k are the coefficients of the polynomial.

[0075] In an embodiment, the error formula is: |y n -y n-1 |=δ, wherein y n is the corrected fitting curve, y n-1 is the basic fitting curve, and δ is the difference between the basic fitting curve and the corrected fitting curve.

[0076] In an embodiment, as shown in Figure 5 , the method for obtaining the basic temperature parameter is: by setting the signal acquisition module 50, connecting the signal acquisition module 50 with the thermocouple 40 to collect the electric signal output by the thermocouple 40, and converting the electric signal into a digital signal output to the computer 60, and obtaining the basic temperature parameter through the calculation of the computer 60.

[0077] Specifically, in this embodiment, the thermocouple 40 outputs the electric signal to the signal acquisition module 50, and then the signal acquisition module 50 converts the electric signal into a digital signal output to the computer 60, and finally the corresponding temperature value is displayed on the screen of the computer 60 through formula conversion, thereby obtaining the basic temperature parameter.

[0078] It should be noted that the method of obtaining the corrected temperature parameter is the same as the method of obtaining the basic temperature parameter, and thus will not be described again.

[0079] In one embodiment, the precision of the thermocouple 40 is δ1, the precision of the signal acquisition module 50 is δ2, and the standard error value is δ3.

[0080] In one embodiment, as shown in FIG. 4, the distance between two adjacent thermocouples 40 is L, which satisfies L≥15 mm. Figure 6

[0081] Specifically, in the present embodiment, L=18 mm.

[0082] Of course, in other alternative embodiments, the distance between two adjacent thermocouples 40 can also be selected as other sizes according to actual conditions.

[0083] It should be noted that if the distance between the thermocouples 40 is too small, it may cause the change of the temperature gradient, thereby affecting the measurement accuracy. If the distance between the thermocouples 40 is too small, it may cause the uneven distribution of the temperature gradient, thereby causing measurement errors.

[0084] It should be noted that by limiting the distance between two adjacent thermocouples 40, the mutual interference between the thermocouples 40 is prevented, and the accuracy of the measurement result is ensured.

[0085] In one embodiment, as shown in FIG. 5, the heating method of the test sample 20 includes the following steps: Figure 3

[0086] Step S31: first pre-heating the test sample 20;

[0087] Step S32: then stably heating the test sample 20;

[0088] Step S33: finally cooling the test sample 20.

[0089] It should be noted that by using the heating method of pre-heating first, then stable heating, and finally cooling, the test cycle process of the aero-engine from the slow state to the maximum flight state and then to the ground state is simulated, and the test process of the irradiation crystal in the engine temperature test is simulated.

[0090] Further, the pre-heating time of the test sample 20 is 10 minutes, the stable heating time of the test sample 20 is 5 minutes, and the cooling time of the test sample 20 is 10 minutes.

[0091] It should be noted that according to the temperature of the irradiation crystal calibration and the setting position of the irradiation crystal on the test sample 20, the pre-heating time, the stable heating time and the cooling time of the test sample 20 can be adjusted.​​

[0092] It should be noted that according to the irradiation crystal temperature measurement range, a suitable temperature calibration range is selected, for example, for a crystal with a temperature measurement range of (500-1400) °C, a temperature calibration range of (450-1450) °C is selected, for a crystal with a temperature measurement range of (150-1450) °C, a temperature calibration range of (100-1500) °C is selected, and a suitable temperature range high-temperature heating equipment is used.

[0093] Specifically, in the present embodiment, the temperature measurement range of the irradiation crystal is (500-1150) °C, and the temperature calibration range is (450-1200) °C.

[0094] Further, the temperature measurement range of the irradiation crystal and the specific data of the temperature calibration range are shown in the following table.

[0095]

[0096]

[0097]

[0098]

[0099] In one embodiment, as shown in FIG. 6, a method for analyzing and processing the irradiation crystal to obtain the irradiation defect recovery rate includes the following steps: Figure 4

[0100] Step S41: using an X-ray diffractometer to perform crystal interpretation on the irradiation crystal to obtain a diffraction spectrum;

[0101] Step S42: analyzing and processing the diffraction spectrum by the computer 60 to obtain the diffraction peak half-height width and the lattice constant;

[0102] Step S43: converting the diffraction peak half-height width and the lattice constant into the irradiation defect recovery rate.

[0103] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and variations fall within the scope defined by the present application.​

Claims

1. A method for multi-temperature point calibration of an irradiated crystal, characterized in that, The method comprises the following steps: Step S10: heating a tube furnace and controlling the core temperature of the tube furnace; Step S20: determining the temperature gradient in the tube furnace and the setting coordinates of the irradiation crystal on the test sample according to the temperature gradient in the tube furnace; Step S30: setting the irradiation crystal on the test sample and placing the test sample in the tube furnace for heating; Step S40: after the heating process is completed, taking out the irradiation crystal from the test sample, analyzing and processing the irradiation crystal, and obtaining the irradiation defect recovery rate; Step S50: obtaining the calibration curve of the irradiation crystal according to the irradiation defect recovery rate; In the step S20, the method for determining the temperature gradient in the tube furnace and the setting coordinates of the irradiation crystal on the test sample comprises the following steps: Step S21: obtaining the basic temperature gradient in the tube furnace through a temperature paint test; Step S22: obtaining basic coordinate parameters according to the basic temperature gradient in the tube furnace and the calibrated temperature of the irradiation crystal, and setting a plurality of thermocouples on the temperature measuring sample according to the basic coordinate parameters; Step S23: placing the temperature measuring sample in the tube furnace for heating treatment to obtain basic temperature parameters; Step S24: obtaining a basic fitting curve through a fitting formula according to the basic coordinate parameters and the basic temperature parameters; Step S25: obtaining corrected coordinate parameters of the thermocouples according to the basic fitting curve and the calibrated temperature of the irradiation crystal, adjusting the positions of the thermocouples on the temperature measuring sample according to the corrected coordinate parameters, and then placing the temperature measuring sample in the tube furnace for heating treatment to obtain corrected temperature parameters; Step S26: obtaining a corrected fitting curve through a fitting formula according to the corrected coordinate parameters and the corrected temperature parameters; Step S27: performing difference calculation on the basic fitting curve and the corrected fitting curve through an error formula, when the difference calculation result is greater than a standard error value δ0, taking the corrected fitting curve at this time as the basic fitting curve, and re-performing step S24; when the difference calculation result is less than the standard error value δ0, performing step S28; Step S28: determining the temperature gradient in the tube furnace through the corrected fitting curve and determining the setting coordinates of the irradiation crystal through the corrected coordinate parameters.

2. The irradiation crystal multi-temperature point calibration method of claim 1, wherein, The fitting formula is: y = a1x + a2x +... + anx + b k-1 where y is temperature, x is distance, a1 to an are coefficients of the polynomial, and b is a constant. k-2 k k ​​​ 3. The irradiation crystal multi-temperature point calibration method of claim 2, wherein, The error formula is: = δ, where y n is the modified fitting curve, y n-1 is the base fitting curve, and δ is the difference between the base fitting curve and the modified fitting curve.

4. The method of claim 1-3, wherein, In the step S23, the method for obtaining the basic temperature parameters is that a signal acquisition module is arranged, the signal acquisition module is connected with the thermocouples to collect the electric signals output by the thermocouples, the electric signals are converted into digital signals and output to a computer, and the basic temperature parameters are obtained through the calculation of the computer.

5. The method of claim 4, wherein, The thermocouple has a precision of δ1, the signal acquisition module has a precision of δ2, and the standard error value δ0= .

6. The method of claim 1-3, wherein, The distance between two adjacent thermocouples is L, and L≥15 mm is satisfied.

7. The method of claim 1-3, wherein, In the step S30, the heating method of the test sample comprises the following steps: Step S31: preheating the test sample; Step S32: stably heating the test sample; Step S33: cooling the test sample.

8. The irradiation crystal multiple temperature point calibration method of claim 7, wherein, The preheating time of the test sample is 10 minutes, the stable heating time of the test sample is 5 minutes, and the cooling time of the test sample is 10 minutes.

9. The method of claim 1-3, wherein, In the step S40, the irradiated crystal is analyzed and processed to obtain the irradiation defect recovery rate, and the method comprises the following steps: Step S41: using an X-ray diffractometer to perform crystal interpretation on the irradiated crystal to obtain a diffraction spectrum; Step S42: analyzing and processing the diffraction spectrum by a computer to obtain a diffraction peak half-height width and a lattice constant; Step S43: converting the diffraction peak half-height width and the lattice constant into an irradiation defect recovery rate.

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