Component joint degree thermal resistance testing method based on natural convection cooling

Abstract

The invention discloses a part joint degree thermal resistance testing method based on natural convection cooling, and relates to the technical field of thermal resistance testing. The problems that in the prior art, testing time is long, efficiency is low, drying cost is increased, and production efficiency is reduced are solved. Through test preparation, real-time monitoring and control, temperature difference calculation and repeated test verification, the thermal conductivity and the processing quality of the joint surface of the component can be quickly judged, the production efficiency is effectively improved, the test cost is reduced, the test conditions are accurately controlled, the thermal steady state is quickly achieved, the test time is remarkably shortened, the test efficiency is improved, and the test cost is reduced. Meanwhile, the drying cost is reduced, the production efficiency is improved, the stability and the reliability of a test result are ensured through repeated testing and verification, the processing quality of a component joint surface can be accurately evaluated, whether the joint process is qualified or not is quantitatively evaluated by establishing a standard temperature difference threshold value, and the reliability of the test result is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal resistance testing, and particularly to a method for testing the thermal resistance of component joint degree based on natural convection cooling. Background Art

[0002] Currently, the existing thermal resistance testing technologies are mainly applied in the manufacturing and detection fields of electronic products. In mechanical processing heat dissipation components such as chip water-cooled plates, thermal resistance testing also has relatively wide applications.

[0003] For example, Chinese Patent Application with Publication No. CN110672659A discloses a double-sided water-cooled plate heat dissipation performance testing device and testing method, including a chiller, a temperature measuring component, and a power supply; the heat dissipation performance of the water-cooled plate is tested through the chiller, the temperature measuring component, and the power supply, and the thermal resistance of the water-cooled plate is calculated using the thermal resistance calculation formula, realizing the heat dissipation performance testing of both sides of the water-cooled plate, and the test results are more accurate.

[0004] For example, Chinese Patent Application with Publication No. CN220039522U discloses a water-cooled plate flow resistance and thermal resistance testing device, which includes a frame body, one side of the frame body is fixedly connected with a controller and a cylinder, a fault indicator light is arranged on the surface of the controller, and one end of the piston rod of the cylinder is fixedly connected with a pressing plate; a first heater is fixedly connected to the surface of the frame body, a thermocouple is arranged on the surface of the first heater, a water tank and a filter are fixedly connected to the other side of the frame body, and a liquid supplement joint is arranged on the outer wall of one side of the water tank; a first group of pipeline components are arranged between the water tank and the filter, and this device simplifies the testing process, aiming to improve the convenience and accuracy of testing.

[0005] For example, Chinese Patent Application with Publication No. CN218823102U discloses a water-cooled plate thermal resistance and flow resistance testing platform, including a main circulation water pump, a first control valve, a first pressure gauge, a second pressure gauge, a flow meter, an electric heater, a thermocouple, and a second control valve; it can better simulate the working scenario of the water-cooled plate, obtain accurate and reliable flow resistance values and thermal resistance values; it can reduce the fluctuation of monitoring data and make the test results more accurate.

[0006] However, the main purpose of the existing thermal resistance testing technology methods is to detect the influence of the welding conditions of internal components on the heat transfer performance. It mainly requires the tester to pass water through the cooling water path of the workpiece to be tested and heat at the heating point until the water and the heating point test heat source reach an overall thermal steady state to obtain the test value. After the test, the product needs to be dried for several minutes before subsequent operations such as assembly and packaging can be carried out. This not only results in a long test time and low efficiency, but also increases the drying cost and reduces the production efficiency. Summary of the Invention

[0007] The object of the present invention is to provide a method for testing the thermal resistance of component joint degree based on natural convection cooling. By conducting tests based on natural convection and transient testing, the testing time can be significantly shortened and the drying step can be omitted. Repeated testing and multiple methods are combined to determine the standard, enabling more accurate judgment, effectively detecting the qualification of the joint process, shortening the testing time, improving production efficiency, and allowing for shipment without additional post-treatment after controlling the testing temperature, greatly reducing the detection cost of traditional water-cooled plate thermal testing, saving testing costs, and improving production efficiency, so as to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A method for testing the thermal resistance of component joint degree based on natural convection cooling, comprising:

[0010] S1: Test preparation: Set up a test platform, place the component to be tested in the test platform, and determine the test parameters of the test platform. Mark the heating point P according to the structural characteristics of the component to be tested heat and the test point P test positions;

[0011] S2: Heating and monitoring: Use a heating device to heat the heating point P heat , and monitor the temperature T of the test heat source in real time during the heating process source . When the test heat source is at the initial temperature, the test heat source is in close contact with the workpiece heating point and continues until the end of the test;

[0012] S3: Temperature measurement: Use a temperature measurement device to measure the temperature at the test point P test . At the same time, another temperature measurement device synchronously collects the temperature data of the heating point P heat . Based on the acquisition results of each temperature measurement device, calculate the temperature difference ΔT = T between the heating point and the test point heating -T testing ;

[0013] S4: Judge the thermal conductivity: Based on the temperature difference ΔT between the heating point and the test point, combined with the preset standard temperature difference threshold ΔT threshold , judge the thermal conductivity of the joint surface of the component to be tested, and then judge whether the processing of the joint surface of the component to be tested is qualified;

[0014] S5: Repeated testing and verification: After completing one test, cool the test heat source and the component to be tested to the initial set temperature Sett i ngT initial , repeat S2 - S4 not less than once, and keep the test conditions consistent for each test. Based on the equivalent thermal resistance R obtained from multiple measurements effective verify whether the joint process of the component to be tested is stable.

[0015] Further, the S1: test preparation specifically includes:

[0016] S101: Determine the process to be measured of the component under test;

[0017] S102: Determine the feature to be measured according to the size and shape of the component under test, construct the framework of the test platform, and determine the corresponding heating plane in contact with the component under test based on the feature to be measured, marked as heating point P heat ;

[0018] S103: According to the position of the heating point P heat and combined with the process to be measured of the component under test, mark the test point P at the corresponding position on the other side of the joint surface of the component under test test , while avoiding the possible abnormal structure areas inside the component under test;

[0019] S104: Conduct an unloaded test on the built test platform, simulate the test process, and observe whether each part of the system operates normally;

[0020] S105: Place the component under test in the test platform qualified for the unloaded test, ensure that the position of the component under test is fixed, and align it with the selected heating point P heat and test point P test positions.

[0021] Further, the heating point position P heat is on one surface of the component under test close to the joint surface, and the test point P test is located at the corresponding position on the other side of the joint surface. Among them, a heat-conducting material is coated between the surface of the component under test and the test heat source.

[0022] Further, in the S2, the temperature T of the test heat source is monitored in real time source , specifically including:

[0023] Collect the temperature T of the test heat source based on the temperature sensor according to the preset acquisition frequency source , and conduct a comparative analysis based on the data acquisition result and the target temperature value T target , and dynamically adjust the power of the heating device based on the comparison result;

[0024] When the temperature T of the test heat source source is lower than the target temperature value T target , and the difference exceeds the lower limit of the allowable fluctuation range, issue the corresponding control instruction to increase the power of the heating device;

[0025] When the temperature T of the test heat source source is higher than the target temperature value T target , and the difference exceeds the upper limit of the allowable fluctuation range, issue the corresponding control instruction to reduce the power of the heating device;

[0026] Meanwhile, draw the temperature T of the test heat source based on the acquisition timestamp source The temperature change curve CT over time actual , ensuring that the temperature change of the heating point P heat meets the expectation before reaching the thermal steady state.

[0027] Furthermore, the S2: Heating and Monitoring further includes:

[0028] Obtain the heat capacity characteristic c, thermal conductivity coefficient k, and target heating rate α of the test heat source, and construct a theoretical curve model CT of the temperature change of the test heat source based on the heat capacity characteristic c, thermal conductivity coefficient k, and target heating rate α of the test heat source exoterica ;

[0029] Compare the actually recorded temperature change curve CT of the test heat source actual with the theoretical curve model CT exoterica to determine whether the actual temperature change of the test heat source meets the expectation;

[0030] If the comparison result exceeds the preset threshold and it is determined that there is an abnormal fluctuation in the actual temperature change curve, then trigger the anomaly detection mechanism to generate an anomaly data packet.

[0031] Furthermore, in the calculation of the temperature difference between the heating point and the test point in the S3, it further includes:

[0032] S301: Confirm the thermal steady state: Based on the real-time monitoring result of the temperature T of the test heat source, when the temperature T of the test heat source source reaches the preset constant temperature T source and the temperature fluctuation amplitude is within the allowable error range within a continuous preset duration, confirm that the heating point P constant has reached the thermal steady state; heat

[0033] S302: Start data acquisition: After confirming that the heating point P heat has reached the thermal steady state, start temperature measurement and data acquisition, and synchronously record the temperature data of the heating point P heat and the test point P test ;

[0034] S303: Select the test duration: The test lasts for a period of time, while ensuring that the temperature of the heating point is stable. Select the time period with relatively stable temperature data and capable of reflecting the thermal conductivity performance of the joint surface of the component under test as the test duration;

[0035] S304: Calculate the temperature difference: During the selected test duration, based on the collected temperature data of the heating point P heat and the test point P test ​The temperature data timestamp synchronizes and aligns the temperature data, and calculates the temperature difference ΔT between the two.

[0036] Further, the preset standard temperature difference threshold in S4 is determined according to the following steps:

[0037] S401: Sample selection and classification: Randomly select a certain number of components of different batches and different specifications from the production line as test samples, number and register the selected test samples, and establish a sample information database;

[0038] S402: Nondestructive testing to obtain the actual joint situation: Use nondestructive testing technology to comprehensively test each test sample, and record the test results into the sample information database based on the test sample number;

[0039] S403: Thermal resistance test to record temperature difference data: Conduct thermal resistance tests on each test sample according to the test process, and calculate the average temperature difference of each sample component;

[0040] S404: Establishment of joint quality etc.: According to the actual joint situation data obtained from nondestructive testing, divide the sample components into different joint quality grades;

[0041] S405: Establish the standard temperature difference threshold: Analyze the distribution law of the temperature difference data corresponding to the components of different joint quality grades, determine the correlation between the temperature difference and the joint quality grade, and determine the temperature difference threshold range corresponding to different joint quality grades.

[0042] Further, S5: Repeated testing and verification also includes:

[0043] Based on the temperature difference ΔT combined with the heating power P heating and the joint area A, calculate the heat flux Q of the joint surface of the measured component, and obtain the equivalent thermal resistance of the measured component. The equivalent thermal resistance calculation formula is as follows:

[0044]

[0045] In the formula, λ represents the thermal conductivity; Q represents the heat power per unit area; δ represents the heat transfer distance; A represents the heat transfer cross-sectional area; Δt represents the temperature difference between the heating point and the test point; R effective represents the equivalent thermal resistance;

[0046] According to the calculated equivalent thermal resistance R effective , compare it with the preset thermal resistance threshold R threshold . If the equivalent thermal resistance R effective is less than or equal to the thermal resistance threshold R threshold , it is determined that the processing of the joint surface of the measured component is qualified; otherwise, if the equivalent thermal resistance R effective is greater than the thermal resistance threshold Rthreshold , it is determined that the machining of the joint surface of the component under test is unqualified;

[0047] Meanwhile, analyze the equivalent thermal resistance data sets obtained from multiple tests. If the data fluctuations are within a reasonable range, it indicates that the bonding process is stable; if the fluctuations are too large, further analyze the reasons or conduct the tests again.

[0048] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0049] Through test preparation, real-time monitoring and control, temperature difference calculation, and repeated test verification, it is possible to quickly judge the thermal conductivity and machining quality of the component joint surface, effectively improve production efficiency, reduce test costs, accurately control test conditions and quickly reach the thermal steady state, significantly shorten the test time, improve test efficiency, reduce drying costs at the same time, improve production efficiency, and through repeated tests and verification, ensure the stability and reliability of test results, which helps to accurately evaluate the machining quality of the component joint surface. By establishing a standard temperature difference threshold, a quantitative evaluation of whether the bonding process is qualified is achieved, enhancing the reliability of test results, thereby improving the overall production quality and efficiency. Description of the Drawings

[0050] Figure 1 It is a flowchart of the thermal resistance test method for the joint degree of components based on natural convection cooling according to the present invention. Detailed Embodiments

[0051] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0052] To solve the technical problems in the prior art that not only result in long test time and low efficiency, but also increase drying costs and reduce production efficiency, please refer to Figure 1 , this embodiment provides the following technical solutions:

[0053] A thermal resistance test method for the joint degree of components based on natural convection cooling, including:

[0054] S1: Test preparation: Build a test platform, place the component under test in the test platform, ensure that the test environment is stable and there is no external interference test heat source, and determine the test parameters of the test platform, including the preheating temperature T of the fixed test heat source preheat , the initial temperature T of the workpiece initial . Meanwhile, mark the heating point P according to the structural characteristics of the component under test heat and the test point Ptest Position;

[0055] S2: Heating and Monitoring: Use a heating device to heat the heating point P heat and monitor the temperature T of the test heat source in real time during the heating process, maintain the temperature of the test heat source constant, so that the heating point reaches a thermal steady state, and when the test heat source is at the initial temperature, the test heat source is in close contact with the workpiece heating point and continues until the end of the test; source

[0056] S3: Temperature Measurement: Use a temperature measurement device to measure the temperature at the test point P test and at the same time another temperature measurement device synchronously collects the temperature data of the heating point P heat . Based on the acquisition results of each temperature measurement device, calculate the temperature difference ΔT = T heating - T testing ;

[0057] S4: Judging the Thermal Conductivity: Based on the temperature difference ΔT between the heating point and the test point, combined with the preset standard temperature difference threshold ΔT threshold , judge the thermal conductivity of the joint surface of the component under test, and then judge whether the processing of the joint surface of the component under test is qualified;

[0058] S5: Repeating Tests and Verification: After completing one test, cool the test heat source and the component under test to the initial set temperature Sett i ngT initial , repeat S2 - S4 not less than once, and keep the test conditions consistent for each test, including the heating power P heating , the test environment E testing , the heating point P heat and the test point P test position, etc. Based on the equivalent thermal resistance R obtained from multiple measurements effective , verify whether the joining process of the component under test is stable.

[0059] In this embodiment, by building a test platform, only parameters such as the preheating temperature of the fixed test heat source and the initial temperature of the workpiece need to be determined, which can quickly make the heating point reach a thermal steady state, greatly shortening the time required for the test, effectively increasing the number of tests per unit time. By accurately measuring the temperature difference between the heating point and the test point and combining with the preset standard temperature difference threshold, the thermal conductivity of the joint surface of the component under test can be accurately judged, and then whether the processing of the joint surface is qualified can be effectively judged, providing a reliable basis for product quality control. Repeating the test multiple times ensures the consistency and stability of product quality, reduces the defective rate, and improves the economic efficiency and market competitiveness of the enterprise.

[0060] In this embodiment, the S1: Test Preparation specifically includes:

[0061] S101: Determine the process to be measured of the component under test, such as the reflow soldering, brazing solder joints of the workpiece under test, etc.;

[0062] S102: Determine the feature to be measured according to the size and shape of the component under test and construct the framework of the test platform, and determine the corresponding heating plane in contact with the component under test based on the feature to be measured, marked as heating point P heat ;

[0063] S103: According to the position of heating point P heat and in combination with the process to be measured of the component under test, mark the test point P at the corresponding position on the other side of the joint surface of the component under test test , ensure that the test point and the heating point are on the same heat conduction path and as close to the joint surface as possible, while avoiding the possible abnormal structure areas inside the component under test, ensure that the temperature measurement can accurately reflect the heat conduction situation of the joint surface, and ensure that the heat conduction path between this point and the heating point is made of homogeneous and stable structural materials except for the process to be measured;

[0064] S104: Conduct an empty-load test on the built test platform, simulate the test process, observe whether each part of the system operates normally, and if there are any abnormalities, adjust and repair them in time to ensure that the test platform meets the test requirements;

[0065] S105: Place the component under test in the test platform that has passed the empty-load test, ensure that the position of the component under test is fixed, and align it with the selected heating point P heat and test point P test The heating point is on one surface of the component under test close to the joint surface, and the test point P heat is located at the corresponding position on the other side of the joint surface. Among them, a heat-conducting material, such as silicone grease, silver paste, etc., which has good heat-conducting performance and is suitable for small-area contact, or graphite gaskets, metal gaskets, etc., which are suitable for large-area contact, is coated between the surface of the component under test and the test heat source, which can effectively reduce heat loss to reduce the contact thermal resistance. test In this embodiment, by clarifying the process to be measured, the subsequent tests can adapt to the heat conduction characteristics of different joint processes, improve the result accuracy, accurately locate the heating point and the test point, ensure that the test point and the heating point are on an effective heat conduction path, avoid abnormal areas, accurately reflect the heat conduction situation of the joint surface, ensure that the position of the component under test is fixed and aligned with the point positions, ensure the consistency of each test, improve the repeatability of the data, and by coating the heat-conducting material, the heat transfer efficiency can be effectively improved and the heat loss can be reduced, thereby improving the accuracy of the test results.

[0066] In this embodiment, in S2, the temperature T of the test heat source is monitored in real time

[0067] In this embodiment, in S2, the temperature T of the test heat source is monitored in real time source, specifically including:

[0068] Collect the temperature T of the test heat source based on the temperature sensor according to the preset acquisition frequency source , and based on the data acquisition result and the target temperature value T target Perform comparative analysis, and dynamically adjust the power of the heating device based on the comparison result;

[0069] When the temperature T of the test heat source source is lower than the target temperature value T target , and the difference exceeds the lower limit of the allowable fluctuation range, issue the corresponding control instruction to increase the power of the heating device, so that the heating device increases the heating power output and speeds up the heating rate of the test heat source;

[0070] When the temperature T of the test heat source source is higher than the target temperature value T target , and the difference exceeds the upper limit of the allowable fluctuation range, issue the corresponding control instruction to reduce the power of the heating device, so that the heating device reduces the heating power output and slows down the heating rate of the test heat source;

[0071] At the same time, draw the temperature change curve CT of the test heat source temperature T source versus time actual , to ensure that the temperature change of the heating point P heat before reaching the thermal steady state conforms to the expectation.

[0072] In this embodiment, the S2: heating and monitoring further includes:

[0073] Obtain the heat capacity characteristic c, thermal conductivity coefficient k and target heating rate α of the test heat source, and construct a theoretical curve model CT of the temperature change of the test heat source based on the heat capacity characteristic c, thermal conductivity coefficient k and target heating rate α of the test heat source exoterica ;

[0074] Compare the actually recorded temperature change curve CT of the test heat source actual with the theoretical curve model CT exoterica to determine whether the actual temperature change of the test heat source conforms to the expectation;

[0075] If the comparison result exceeds the preset threshold and it is determined that the actual temperature change curve has abnormal fluctuations, then trigger the anomaly detection mechanism, generate an anomaly data packet containing the time stamp H - temperature value T - environmental parameter E, such as the heating rate is too fast or too slow, the temperature suddenly jumps, etc., and it is necessary to check in time whether there are problems with the heating device, temperature sensor and test environment, etc.

[0076] In this embodiment, the temperature of the test heat source is monitored in real time and the power of the heating device is dynamically adjusted to ensure that the temperature of the test heat source is stable near the target value. When the temperature deviates from the allowable fluctuation range, the power can be automatically adjusted to make the heating rate reasonable, avoiding too high or too low temperature, providing a reliable guarantee for the heating point to reach the thermal steady state. By constructing a theoretical curve model and comparing it with the actual temperature change curve, it is possible to accurately judge whether the temperature change of the test heat source meets the expectations. This not only improves the stability and reliability of the test process, ensures the accuracy of the test results, but also can quickly locate and solve possible equipment failures or environmental interference problems, effectively reducing the test error and time cost, and improving the efficiency and quality of the entire thermal resistance test process.

[0077] In this embodiment, calculating the temperature difference between the heating point and the test point in S3 further includes:

[0078] S301: Confirm the thermal steady state: Based on the real-time monitoring result of the temperature T of the test heat source, when the temperature T of the test heat source source reaches the preset constant temperature T source and the temperature fluctuation amplitude is within the allowable error range within a continuous preset time period, confirm that the heating point P constant has reached the thermal steady state; heat

[0079] S302: Start data acquisition: After confirming that the heating point P heat has reached the thermal steady state, start temperature measurement and data acquisition, and synchronously record the temperature data of the heating point P heat and the test point P test ;

[0080] S303: Select the test duration: The test lasts for a period of time, while ensuring that the temperature of the heating point is stable. Select the time period during which the temperature data is relatively stable and can reflect the thermal conduction performance of the joint surface of the component under test as the test duration to ensure the accuracy and representativeness of the data acquisition;

[0081] S304: Calculate the temperature difference: During the selected test duration, synchronize and align the temperature data based on the timestamps of the temperature data of the heating point P heat and the test point P test , and calculate the temperature difference ΔT between the two.

[0082] In this embodiment, by confirming the thermal steady state before starting data acquisition, interference from data in the non-steady state is avoided, ensuring that the collected data can truly reflect the thermal conduction characteristics of the component. By reasonably selecting the test duration, the collected temperature data is ensured to be stable and representative, improving the accuracy and effectiveness of the data. After synchronizing and aligning the temperature data of the heating point and the test point according to the time stamp, the temperature difference is calculated, enabling the temperature difference to accurately reflect the actual temperature difference between the two, providing a reliable basis for subsequent judgment of the thermal conductivity and processing quality of the tested component's joint surface, and enhancing the scientific nature and reliability of the entire thermal resistance test method.

[0083] In this embodiment, a preset standard temperature difference threshold is set in S4 and determined according to the following steps:

[0084] S401: Sample selection and classification: Randomly select a certain number of components of different batches and specifications from the production line as test samples, covering various possible joint degrees, including ideal joints, slightly defective joints, severely defective joints, etc. Number and register the selected test samples, establish a sample information database, and record basic information such as the model, size, and production batch of the samples.

[0085] S402: Nondestructive testing to obtain the actual joint situation: Use nondestructive testing techniques such as ultrasonic testing and X-ray testing to comprehensively test each test sample, and record the test results in the sample information database based on the test sample number.

[0086] S403: Thermal resistance test to record temperature difference data: Conduct thermal resistance tests on each test sample according to the test process, and calculate the average temperature difference of each sample component.

[0087] S404: Establishment of joint quality, etc.: According to the actual joint situation data obtained from nondestructive testing, divide the sample components into different joint quality grades, such as qualified and unqualified.

[0088] S405: Establish a standard temperature difference threshold: Analyze the distribution law of the temperature difference data corresponding to components of different joint quality grades, determine the correlation between the temperature difference and the joint quality grade, and determine the temperature difference threshold range corresponding to different joint quality grades by fitting curves, establishing mathematical models, etc., thereby establishing the corresponding standard for whether the joint process is qualified based on the temperature difference.

[0089] In this embodiment, components with different joint degrees are detected by means of ultrasonic waves, X-rays, etc. to obtain the actual joint situation data of these components. At the same time, thermal resistance tests are conducted on these components, and the corresponding temperature difference data is recorded. Through comparative analysis of a large amount of experimental data, a corresponding standard for whether the joint process is qualified based on the temperature difference is established, and it is determined by comparing the thermal resistance test data, providing a scientific and accurate reference for judging whether the joint process of the tested component is qualified, and improving the practicality and reliability of the thermal resistance test method.

[0090] In this embodiment, step S5: Repeated testing and verification further includes:

[0091] Based on the temperature difference ΔT, combined with the heating power P heating and the bonding area A, calculate the heat flux Q of the bonding surface of the component under test, and obtain the equivalent thermal resistance of the component under test. The formula for calculating the equivalent thermal resistance is as follows:

[0092]

[0093] In the formula, λ represents the thermal conductivity; Q represents the heat power per unit area; δ represents the heat transfer distance; A represents the heat transfer cross-sectional area; Δt represents the temperature difference between the heating point and the test point; R effective represents the equivalent thermal resistance;

[0094] According to the calculated equivalent thermal resistance R effective , compare it with the preset thermal resistance threshold R threshold . If the equivalent thermal resistance R effective is less than or equal to the thermal resistance threshold R threshold , it is determined that the processing of the bonding surface of the component under test is qualified; otherwise, if the equivalent thermal resistance R effective is greater than the thermal resistance threshold R threshold , it is determined that the processing of the bonding surface of the component under test is unqualified;

[0095] At the same time, analyze the equivalent thermal resistance data sets obtained from multiple tests. If the data fluctuations are within a reasonable range, it indicates that the bonding process is stable; if the fluctuations are too large, further analyze the reasons or retest.

[0096] In this embodiment, by comprehensively considering multiple factors, the thermal resistance calculation can more accurately reflect the heat conduction characteristics of the bonding surface of the component under test. By comparing the equivalent thermal resistance with the preset thermal resistance threshold, it is determined whether the processing is qualified, providing a clear and quantitative standard for quality assessment, improving the objectivity and accuracy of judgment. Analyzing the equivalent thermal resistance data sets of multiple tests can effectively evaluate the stability of the bonding process, help improve the process and optimize the production process in a timely manner, reduce the defective rate, and improve the overall production quality and efficiency.

[0097] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A component joint thermal resistance test method based on natural convection cooling, characterized in that: include: S1: Test preparation: Build the test platform, place the tested component on the test platform, and determine the test parameters of the test platform. At the same time, mark the heating point P according to the structural characteristics of the tested component. heat With test point P test Location; S2: Heating and monitoring: Use a heating device to heat the heating point P heat Heat and monitor the test heat source temperature T in real time during the heating process source , and when the test heat source is at the initial temperature, the test heat source is in close contact with the heating point of the workpiece and continues to be in close contact until the end of the test; S3: Temperature measurement: Use a temperature measuring device to measure the temperature at the test point P test The temperature of the heating point P is measured while another temperature measuring device simultaneously collects the temperature of the heating point P heat Based on the temperature data collected by each temperature measuring device, the temperature difference ΔT=T between the heating point and the test point is calculated. heating -T testing ; S4: Determine thermal conductivity: Based on the temperature difference ΔT between the heating point and the test point, combined with the preset standard temperature difference threshold ΔT threshold , determine the thermal conductivity of the joint surface of the tested component, and then determine whether the processing of the joint surface of the tested component is qualified; S5: Repeat test and verification: After completing a test, cool the test heat source and the tested component to the initial setting temperature SettingT initial Repeat S2-S4 at least once, and keep the test conditions consistent for each test. Based on the equivalent thermal resistance R obtained by multiple measurements effective Verify that the bonding process of the tested parts is stable.

2. The component joint degree thermal resistance test method based on natural convection cooling according to claim 1, characterized in that: S1: Test preparation, specifically includes: S101: Determine the tested process of the tested component; S102: Determine the measured features according to the size and shape of the measured component and build the framework of the test platform, and determine the corresponding heating plane in contact with the measured component based on the measured features, marking it as the heating point P heat ; S103: According to the heating point P heat Position, combined with the tested process of the tested component, mark the test point P at the corresponding position on the other side of the joint surface of the tested component test , while avoiding possible structural abnormalities inside the tested component; S104: Perform a no-load test on the built test platform, simulate the test process, and observe whether each part of the system operates normally; S105: Place the tested component on a test platform that has passed the no-load test, and ensure that the tested component is fixed in position and aligned with the selected heating point P. heat and test point P test Position alignment.

3. The component joint degree thermal resistance test method based on natural convection cooling according to claim 2, characterized in that: The heating point P heat On a surface of the tested component close to the joint surface, the test point P test Located at a corresponding position on the other side of the joint surface, a heat-conducting material is coated between the surface of the tested component and the test heat source.

4. The component joint degree thermal resistance test method based on natural convection cooling according to claim 3, characterized in that: The temperature T of the test heat source is monitored in real time in S2 source , specifically including: Based on the temperature sensor, the test heat source temperature T is collected according to the preset collection frequency source , and based on the data collection results and the target temperature value T target Conduct comparative analysis and dynamically adjust the power of the heating device based on the comparison results; When the test heat source temperature T source Below target temperature T target , and when the difference exceeds the lower limit of the allowable fluctuation range, a corresponding control instruction is issued to increase the power of the heating device; When the test heat source temperature T source Higher than the target temperature T target , and when the difference exceeds the upper limit of the allowable fluctuation range, a corresponding control instruction is issued to reduce the power of the heating device; At the same time, the test heat source temperature T is plotted based on the acquisition timestamp source Temperature change curve CT over time actual , ensure that the heating point P heat The temperature changes were as expected before reaching thermal steady state.

5. The component joint degree thermal resistance test method based on natural convection cooling according to claim 4, characterized in that: S2: Heating and monitoring, further comprising: Obtain the heat capacity characteristic c, thermal conductivity coefficient k and target heating rate α of the test heat source, and build a theoretical curve model CT of the temperature change of the test heat source based on the heat capacity characteristic c, thermal conductivity coefficient k and target heating rate α of the test heat source exoterica ; The actual temperature change curve CT of the test heat source will be recorded actual Theoretical curve model CT exoterica Compare and judge whether the actual temperature change of the test heat source is in line with expectations; If the comparison result exceeds the preset threshold and it is judged that the actual temperature change curve has abnormal fluctuations, the pear will trigger the abnormal detection mechanism and generate an abnormal data packet.

6. The component joint degree thermal resistance test method based on natural convection cooling according to claim 5, characterized in that: The calculation of the temperature difference between the heating point and the test point in S3 also includes: S301: Confirm thermal steady state: Based on the test heat source temperature T source Real-time monitoring results, when the test heat source temperature T source Reach the preset constant temperature T constant When the temperature fluctuation range is within the allowable error range within the preset time, the heating point P is confirmed. heat Thermal steady state has been reached; S302: Start data collection: After confirming the heating point P heat After reaching thermal steady state, temperature measurement and data acquisition are started, and the heating point P is recorded simultaneously. heat and test point P test Temperature data; S303: Selecting the test duration: The test lasts for a period of time, while ensuring that the temperature of the heating point is stable, and a period of time when the temperature data is relatively stable and can reflect the thermal conductivity performance of the joint surface of the tested component is selected as the test duration; S304: Calculate the temperature difference: within the selected test time, based on the collected heating point P heat and test point P test The temperature data timestamp is used to synchronize the temperature data and calculate the temperature difference ΔT between the two.

7. The component joint degree thermal resistance test method based on natural convection cooling according to claim 6, characterized in that: The standard temperature difference threshold value is preset in S4 and is determined according to the following steps: S401: Sample selection and classification: Randomly select a certain number of parts of different batches and specifications from the production line as test samples, number and register the selected test samples, and establish a sample information database; S402: Nondestructive testing to obtain actual joint conditions: Use nondestructive testing technology to conduct a comprehensive test on each test sample, and record the test results in the sample information database based on the test sample number; S403: Thermal resistance test to record temperature difference data: Perform thermal resistance test on each test sample according to the test process, and calculate the average temperature difference of each sample component; S404: Establishing the quality of the joint, etc.: Classifying the sample parts into different joint quality levels according to the actual joint condition data obtained by nondestructive testing; S405: Establishing a standard temperature difference threshold: Analyze the distribution law of temperature difference data corresponding to components with different joining quality levels, determine the correlation between temperature difference and joining quality level, and determine the temperature difference threshold range corresponding to different joining quality levels.

8. The component joint degree thermal resistance test method based on natural convection cooling according to claim 7, characterized in that: S5: Repeated testing and verification, further comprising: Based on the temperature difference ΔT combined with the heating power P heating and the joint area A, calculate the heat flux Q of the joint surface of the measured component, and obtain the equivalent thermal resistance of the measured component. The calculation formula of the equivalent thermal resistance is as follows: In the formula, λ represents thermal conductivity; Q represents the heat power per unit area; δ represents the heat transfer distance; A represents the heat transfer cross-sectional area; Δt represents the temperature difference between the heating point and the test point; R effective Expressed as equivalent thermal resistance; According to the calculated equivalent thermal resistance R effective , and the preset thermal resistance threshold R threshold For comparison, if the equivalent thermal resistance R effective Less than or equal to the thermal resistance threshold R threshold , then the processing of the joint surface of the tested component is determined to be qualified; otherwise, if the equivalent thermal resistance R effective Greater than the thermal resistance threshold R threshold , then it is judged that the machining of the joint surface of the tested component is unqualified; At the same time, the equivalent thermal resistance data group obtained from multiple tests is analyzed. If the data fluctuation is within a reasonable range, it indicates that the bonding process is stable; if the fluctuation is too large, the cause is further analyzed or the test is repeated.

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