A Bearing Self-Calibration Temperature Monitoring Method Based on Dual-Emission Fluorescent Composite Materials

Abstract

A bearing self-calibrating temperature monitoring method based on a dual-emission fluorescent composite material, comprising the following steps: (1) By preparing a cadmium selenide quantum dot and Eu-BTC metal-organic framework composite material thin film, different temperature calibrations are carried out to obtain the photoluminescence intensity ratio-temperature calibration curve of the sensor thin film; (2) The prepared quantum dot-metal-organic framework structure composite material thin film is used as a sensor and pasted on the surface of the bearing rotating component to be measured. Using a laser as the excitation light source, the photoluminescence energy of the spectral information is calculated and compared with the photoluminescence intensity ratio-temperature calibration curve in step (1), so as to obtain the temperature of the bearing component to be measured and realize the real-time measurement of the temperature of the bearing rotating component; The present invention has the advantages of high versatility, good stability, self-calibration, non-contact, etc., provides innovative ideas and methods for bearing component temperature monitoring, and at the same time provides necessary technical reference for temperature monitoring in the field of major equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of non-contact operating condition monitoring of rotating components in mechanical engineering, and particularly relates to a bearing self-calibrating temperature monitoring method based on dual-emission fluorescent composite materials, specifically a method for self-calibrating temperature monitoring of a bearing rotating component based on a dual-emission quantum dot-metal organic framework composite material. Background Art

[0002] As a core component of equipment in various major industrial fields such as aerospace, robotics, transportation, and machine tools, bearings play a decisive role in the service performance and rotational accuracy of rotating components of the equipment. Bearings are also known as the "heart" of the rotary support system. The operating state of the bearing is of great significance for the long-term high-speed stable operation of the equipment. By monitoring the state of the bearing, understanding the working condition of the bearing and making timely feedback, it is possible to effectively give early warnings of the operating faults of the equipment, avoid the occurrence of safety accidents, and is of great significance for extending the life of the equipment and ensuring the safety of the equipment. At present, with the increasing depth of mechanical intelligence, the requirements for various indicators of bearings in various extreme working environments are becoming more and more stringent. At the same time, the demand for intelligent monitoring of internal rotating components such as the inner ring and cage of the bearing is increasing day by day. Especially in the fields of aerospace and the like, the online monitoring demand for the operating state such as the temperature rise of the rotating components of the bearing is gradually increasing. Temperature monitoring is of great significance for analyzing the frictional heat generation of the bearing structural components, optimizing the internal structure of the bearing, and increasing the operating speed and life of the bearing.

[0003] At present, with the development of various detection technologies, the detection technology for the operating state of bearings has also received attention. However, due to the compact structure of bearings and the narrow space environment where bearings are located, the temperature measurement technology for bearing rotating components is limited. Traditional contact temperature measurement uses the resistance sensitivity of certain materials to temperature to prepare thin film sensors to measure the temperature of bearing components. This type of sensor has high requirements for the space environment of bearings and is generally installed on bearing components by embedding means, which has a certain invasiveness to the bearing structure and hinders the further application of this type of sensor. Currently, in the field of non-contact testing technology, there is little research on the non-contact temperature detection technology for bearing rotating components. In recent years, with the improvement of camera sensitivity and the development of infrared technology, using infrared technology to measure temperature has become a powerful tool, but there are still some defects in infrared detection technology. Infrared testing requires rolling bearings to be in an open environment, and it is difficult to carry out temperature monitoring for the enclosed space where bearings actually serve. Moreover, the spatial resolution of this technology is usually limited to the infrared wavelength, which limits the real-time monitoring application of the temperature in the contact area of bearings. In addition, using quantum dots for temperature detection of bearing rotating components has become an emerging field. By using the photoluminescence and optical sensitivity to temperature of certain quantum dots, temperature measurement can be achieved, which has the characteristics of non-contact and high sensitivity to temperature. However, the temperature tolerance of quantum dots is poor, and the optical performance of quantum dot sensors decreases at higher temperatures and is prone to quenching. And the accuracy of quantum dot sensors is low. During the monitoring process using quantum dots, the emission laser intensity and distance need to be fixed, which limits their application as sensors. Therefore, how to achieve highly versatile, highly accurate, non-contact temperature detection of bearing components remains a difficult problem in current bearing condition detection technology.

[0004] The patent with the publication number CN 112345113 A discloses a small quantum dot temperature sensor. Although it has a simple structure and low cost, it uses pure quantum dots as sensing materials and has poor temperature tolerance, and its PL peak intensity is affected by environmental factors such as ultraviolet light intensity and the distance of the exciter, resulting in errors. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide a bearing self-calibrating temperature monitoring method based on a dual-emission fluorescent composite material. By adopting a composite structure of cadmium selenide quantum dots and lanthanide metal-organic frameworks, according to the opposite characteristics that the photoluminescence intensity of quantum dots shows attenuation and the lanthanide metal-organic frameworks show enhancement with temperature respectively, using the ratio of the emission peak intensities of the two materials, the requirements for laser intensity and distance of traditional luminescent materials are avoided, and the temperature operation monitoring of the rotating components of rolling bearings is realized, and it has high accuracy and temperature tolerance.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A bearing self-calibrating temperature monitoring method based on a dual-emission fluorescent composite material, comprising the following steps:

[0008] (1). Preparation and temperature calibration of the quantum dot-metal organic framework structure composite material:

[0009] Prepare the quantum dot-metal organic framework structure composite material, and use it as a sensor material to perform different temperature calibrations on it to obtain the sensor material photoluminescence intensity ratio-temperature calibration curve; the quantum dot-metal organic framework structure composite material as a sensor is obtained by using cadmium selenide quantum dots and Eu-BTC lanthanide metal organic framework structure as the composite material temperature sensor, and introducing the metal organic framework material as a reactor during the quantum dot synthesis process, thereby introducing quantum dots into the pores of the metal framework to obtain the composite material, or mixing quantum dots and Eu metal organic framework materials to obtain the composite material; then prepare the sensor thin film by means of coating and film formation;

[0010] (2). Real-time measurement of temperature:

[0011] Use the prepared quantum dot-metal organic framework structure composite material thin film as a sensor. The method is to paste the thin film sensor on the end face of the bearing to-be-tested moving component. Use a laser as the excitation light source, irradiate the excitation light to the sensor position, make it excited to emit photoluminescence, and the generated fluorescence is analyzed by a spectrometer and then transmitted to the PC side. Calculate the photoluminescence intensity ratio of the quantum dot and metal organic framework spectral information, and compare it with the sensor photoluminescence intensity ratio-temperature calibration curve, so as to obtain the temperature information at the bearing rotating component, and realize the non-contact real-time measurement of the bearing rotating component.

[0012] The bearing to-be-tested moving component described in step (1) includes a rotating inner ring or a cage.

[0013] The quantum dot-metal organic framework structure composite material described in step (1) as a sensor, its photoluminescence spectrum is composed of the superposition of the emission spectra of quantum dots and metal organic frameworks, and has two fluorescence peaks at the same time. The fluorescence peak intensity of the Eu-BTC material shows an increasing trend with the increase of temperature, and the fluorescence peak intensity of cadmium selenide (CdSe) quantum dots decreases with temperature. The photoluminescence emission peak intensities of the two materials are compared to form a dual-emission self-calibrating sensor material, and the fluorescence intensity ratio of quantum dots to metal organic frameworks shows an exponential growth trend with temperature.

[0014] In step (i), by introducing a metal-organic framework material as a reactor during the quantum dot synthesis process, quantum dots are introduced into the pores of the metal framework to obtain a composite material. The specific method is as follows:

[0015] (1) Add 0.4 - 1.2 mmol of europium nitrate hexahydrate Eu(NO3)3·6H2O (178 - 534 mg) and 2 - 6 mmol of sodium acetate NaAC (164 - 492 mg) to 20 - 60 ml of N,N-dimethylformamide DMF, and stir until the reaction solution is dissolved. Then, introduce 0.9 - 2.7 mmol of 1,3,5-benzenetricarboxylic acid H3BTC (188 - 564 mg) into the reaction solution under continuous stirring to produce a white suspension. Subsequently, the solution is stirred for 8 - 24 hours. Finally, the prepared Eu-BTC metal-organic framework solution is dried by a centrifuge to obtain white Eu-BTC powder.

[0016] (2) Add 40 - 120 mg of selenium Se powder to a mixture of 2 - 6 ml of octadecene and 0.6 - 1.2 ml of tri-n-octylphosphine TOP, and dissolve it by ultrasonic wave to form a selenium precursor solution. Put 65 - 195 mg of cadmium oxide CdO into a mixture of 6 - 10 ml of octadecene and 1 - 3 ml of oleic acid, and dissolve it at 120 - 150 °C to form a cadmium precursor. Raise the temperature of the cadmium precursor solution to 220 - 240 °C, then add 100 - 350 mg of the prepared Eu-BTC powder, and then add 2.6 - 7.2 ml of the selenium precursor solution in an anaerobic environment. The reaction proceeds for 5 - 30 minutes. The obtained mixed solution is collected by centrifugation, and then centrifugally purified in 10 - 30 ml of n-hexane to obtain the CdSe@Eu-BTC dual-emission fluorescent composite material.

[0017] The temperature calibration curve in step (i) is specifically as follows:

[0018] Record the photoluminescence spectra of the quantum dots and the metal-organic framework in the composite material, obtain the photoluminescence spectra of the two materials at different temperatures, and calculate the ratio of the spectral peak intensities corresponding to the two materials as the y-axis of the temperature calibration. Take different temperatures as the x-values, fit the recorded points, and obtain the photoluminescence intensity ratio - temperature calibration curve of the quantum dot - metal-organic framework structure composite material.

[0019] The non-contact real-time measurement of the bearing rotation assembly in step (ii) is specifically as follows:

[0020] (1) Construction of a synchronous monitoring platform: Adjust the placement of the quantum dot-metal organic framework composite thin film sensor according to the different components to be tested of the bearing; when the rotating component to be tested is the rotating inner ring of the bearing, attach the thin film sensor 1 to the end face 2 of the inner ring; if the component to be tested is a retaining frame component, place the thin film sensor 1 at the end face 3 of the retaining frame, use a laser 4 as an excitation light source, connect one end of the incident optical fiber 6 to the first probe 5, and the other end to the laser 4, align the first probe 5 with the center position of the thin film sensor 1, and irradiate the excited ultraviolet light to the center position of the sensor through the incident optical fiber 6 and the first probe 5 to excite the composite material sensor to achieve photoluminescence, and use the second probe 7 and optical fiber 8 for receiving to collect the photoluminescence spectrum emitted by the sensor and transmit it to the spectrometer 9. The spectral information is transmitted to the PC terminal 10 through the spectrometer 9;

[0021] (2) Real-time temperature monitoring: For bearings in experimental or service conditions, start the synchronous monitoring platform built in step (1), compare the peak intensity ratio of CdSe quantum dots and Eu-BTC metal organic framework in the spectral information of the bearing at different times under the rotation state obtained by the PC terminal 10 with the photoluminescence intensity-temperature calibration curve of the thin film sensor, and obtain the real-time temperature data of the rolling bearing test assembly.

[0022] Advantages of the present invention:

[0023] (1) Based on the temperature sensitivity of cadmium selenide quantum dots and lanthanide metal organic framework materials, ultraviolet light is used to excite quantum dot-metal organic framework composite materials to achieve photoluminescence of quantum dots and metal organic frameworks. The photoluminescence intensity of quantum dots and lanthanide metal organic frameworks show opposite characteristics of attenuation and enhancement respectively with temperature. By comparing the different emission peak intensities of the two materials, the requirements of traditional luminescent materials for laser intensity and distance are avoided, and self-calibration monitoring of the temperature of the bearing rotating component is achieved with high accuracy.

[0024] (2) Compared with traditional temperature measurement methods, quantum dots and metal-organic frameworks have better stability, lower requirements for experimental environment, and higher versatility.

[0025] (2) Based on the non-contact and embedded system without modification of the bearing rotating assembly, the temperature monitoring of the bearing rotating assembly is realized, which is especially suitable for the temperature monitoring of high-speed bearings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the construction of the synchronous monitoring platform of the present invention.

[0027] Figure 2 Schematic diagram of the temperature acquisition principle in this method. Detailed implementation manners

[0028] The present invention will be further described in detail below with reference to the accompanying drawings.

[0029] A bearing self-calibrating temperature monitoring method based on a dual-emission fluorescent composite material includes the following steps:

[0030] (1). Preparation and temperature calibration of a quantum dot-metal organic framework composite material:

[0031] Prepare a quantum dot-Eu-BTC metal organic framework composite material, use it as a sensor material to calibrate it at different temperatures, obtain the photoluminescence spectra at different temperatures, and calculate the ratio of the spectral peak intensities corresponding to the two materials respectively. Take the ratio of the luminescence intensities of the quantum dot and the metal organic framework material as the y value, and the temperature as the x axis to obtain the photoluminescence intensity ratio-temperature calibration curve of the quantum dot-metal organic framework composite material. The quantum dot-metal organic framework composite material sensor is a composite material temperature sensor using CdSe quantum dots and Eu-BTC lanthanide metal organic frameworks, and the sensor film is prepared by a coating and film-forming method.

[0032] As a sensor, the preparation method of the quantum dot-metal organic framework composite material can be to introduce the metal organic framework material as a reactor during the synthesis of the quantum dot, so as to introduce the quantum dot into the pores of the metal framework to obtain the composite material. The specific preparation process is as follows:

[0033] (1) Add 0.8 mmol of europium nitrate hexahydrate Eu(NO3)3·6H2O 356 mg and 4 mmol of sodium acetate NaAC 328 mg to 40 ml of N,N-dimethylformamide DMF, and stir until the reaction solution is dissolved; then, introduce 1.8 mmol of 1,3,5-benzenetricarboxylic acid H3BTC 376 mg into the reaction solution under continuous stirring, and an immediate white suspension will be produced; subsequently, the solution is stirred for 12 hours, and finally, the prepared Eu-BTC metal organic framework solution is dried by a centrifuge to obtain white Eu-BTC powder.

[0034] (2) Add 78 mg of selenium Se powder to a mixture of 4 ml of octadecene and 1 ml of TOP (trioctylphosphine), and dissolve it by ultrasonic waves to form a selenium precursor solution; put 130 mg of cadmium oxide CdO into a mixture of 8 ml of octadecene and 2 ml of oleic acid, and dissolve it at 120 °C to form a cadmium precursor; raise the temperature of the cadmium precursor solution to 225 °C, then add 300 mg of the prepared Eu-BTC powder, and then add 5 ml of the selenium precursor solution in an anaerobic environment, and the reaction proceeds for 20 minutes. In order to obtain the finally manufactured CdSe@Eu-BTC product, collect the obtained mixed solution by centrifugation, and then centrifuge and purify it in 20 ml of n-hexane to obtain the CdSe@Eu-BTC dual-emission fluorescent composite material.

[0035] In this way, a metal-organic framework material is introduced as a reactor during the synthesis of quantum dots, so that the quantum dots are introduced into the pores of the metal framework to obtain a composite material, or a composite material is obtained by mixing quantum dots and Eu metal-organic framework materials; then a sensor film is prepared by coating and forming a film.

[0036] The quantum dot-metal organic framework structure composite material is used as a sensor, and its photoluminescence spectrum is composed of the superposition of the emission spectra of the quantum dots and the metal organic framework, with two fluorescence peaks. The fluorescence peak intensity of the Eu-BTC material shows an increasing trend with the increase of temperature, and the fluorescence peak intensity of cadmium selenide (CdSe) quantum dots decreases with temperature. By comparing the photoluminescence emission peak intensities of the two materials, the requirements for laser intensity and distance of traditional luminescent sensor materials are avoided, thus forming a dual-emission self-calibrating sensor material, and the fluorescence intensity ratio of the quantum dots to the metal organic framework shows an exponential growth trend with temperature.

[0037] For the quantum dot-metal organic framework structure composite material, by controlling the reaction time in the preparation of quantum dots, the photoluminescence fluorescence peak wavelength of cadmium selenide (CdSe) quantum dots should be as far away as possible from the peak wavelength of the Eu-BTC metal organic framework structure material to avoid interference between the two.

[0038] (2) Real-time measurement of temperature: [[ID=..]](2) Real-time measurement of temperature:

[0039] Use the prepared quantum dot-metal organic framework structure composite material film as a sensor. The method is to paste the film sensor on the end face of the bearing to-be-tested moving component, use a laser as an excitation light source, irradiate the excitation light to the sensor position to make it excited to emit photoluminescence, and the generated fluorescence is analyzed by a spectrometer and then transmitted to the PC side. Calculate the photoluminescence intensity ratio of the spectral information of the quantum dots and the metal organic framework, and compare it with the sensor photoluminescence intensity ratio - temperature calibration curve, so as to obtain the temperature information at the bearing rotating component, and realize the non-contact real-time measurement of the bearing rotating component.

[0040] Taking the measurement of the rotating inner ring of the bearing as an example:

[0041] (1) Establishment of the synchronous monitoring platform: Refer to Figure 1 , according to the different components to be measured of the bearing, adjust the placement position of the quantum dot-metal organic framework composite film sensor; when the rotating component to be tested is the rotating inner ring of the bearing, then attach the film sensor 1 to the end face 2 of the inner ring by means of pasting, etc.; if the component to be tested is the cage component, then place the film sensor 1 at the end face 3 of the cage. As Figure 1 , taking the inner ring test as an example for illustration, attach the film sensor 1 to the end face 2 of the inner ring by means of pasting, etc. The temperature test platform of the cage adopts the same platform establishment method as that of the inner ring test. Use the laser 4 as the excitation light source. One end of the incident optical fiber 6 is connected to the first probe 5, and the other end is connected to the laser 4. Align the first probe 5 to the center position of the film sensor, and irradiate the excited ultraviolet light to the center position of the sensor through the incident optical fiber 6 and the first probe 5 to excite the composite material sensor to achieve photoluminescence. Use the second probe 7 and the optical fiber 8 for reception to collect the photoluminescence spectrum emitted by the sensor and transmit it to the spectrometer 9. The spectral information is sent to the PC terminal 10 through the spectrometer 9.

[0042] (2) Real-time monitoring of temperature: Refer to Figure 2 , for the bearing under experimental or service conditions, start the synchronous monitoring platform established in step (1), record the ratio P2 / P1 of the peak intensities of the CdSe quantum dot P1 and the Eu-BTC metal organic framework P2 in the spectral information received at different moments under the rotating state of the bearing obtained by the PC terminal 10, and compare it with the photoluminescence-temperature calibration curve of the sensor ( Figure 2 right figure in the following, obtained by calibrating the quantum dot-metal organic framework composite film sensor before testing), so as to obtain the real-time temperature data of the rolling bearing test component.

[0043] The present invention utilizes the photoluminescence characteristics of CdSe quantum dots and Eu-BTC metal organic framework materials at different temperatures. The trend of the luminescence intensity of CdSe quantum dots is inversely proportional to the temperature, and the luminescence intensity of the Eu-BTC metal organic framework material is directly proportional to the increase in temperature. The dual-emission quantum dot-metal organic framework structure composite material sensor prepared by the present invention makes the photoluminescence intensity ratio-temperature calibration curve approximately exponential within a specific temperature range.

Claims

1. A bearing self-calibration temperature monitoring method based on dual-emission fluorescence composite material, characterized in that: The following steps are involved: (I) Preparation and temperature calibration of quantum dot-metal organic framework composite materials: A quantum dot-metal organic framework structure composite material is prepared and used as a sensor material to calibrate it at different temperatures to obtain a photoluminescence intensity ratio-temperature calibration curve of the sensor material; the quantum dot-metal organic framework structure composite material is used as a sensor, specifically: cadmium selenide quantum dots and Eu-BTC lanthanide metal organic framework structure are used as composite temperature sensors, the metal organic framework material is introduced as a reactor during the quantum dot synthesis process, thereby introducing the quantum dots into the pores of the metal framework to obtain a composite material, or the quantum dots and Eu metal organic framework material are mixed to obtain a composite material; and a sensor film is then prepared by coating. (2) Real-time measurement of temperature: The prepared quantum dot-metal organic framework structure composite material film is used as a sensor. The thin film sensor is pasted on the end face of the moving component to be tested in the bearing. A laser is used as an excitation light source to irradiate the excitation light to the sensor position, causing it to be stimulated to photoluminesce. The generated fluorescence is analyzed by a spectrometer and transmitted to the PC end. The photoluminescence intensity ratio of the quantum dot and metal organic framework spectral information is calculated and compared with the sensor photoluminescence intensity ratio-temperature calibration curve to obtain the temperature information of the bearing rotating component, thereby realizing non-contact real-time measurement of the bearing rotating component.

2. The bearing self-calibration temperature monitoring method based on dual-emission fluorescence composite material according to claim 1 is characterized in that: The bearing moving component to be tested includes a rotating inner ring or a retaining frame.

3. The bearing self-calibration temperature monitoring method based on dual-emission fluorescence composite material according to claim 1 is characterized in that: The quantum dot-metal organic framework structure composite material is used as a sensor. Its photoluminescence spectrum is formed by the superposition of two emission spectra of quantum dots and metal organic framework, and it also has two fluorescence peaks. The fluorescence peak intensity of the Eu-BTC material shows an increasing trend with increasing temperature, while the fluorescence peak intensity of the cadmium selenide (CdSe) quantum dots decreases with temperature. The photoluminescence emission peak intensities of the two materials are compared to form a dual-emission self-calibration sensor material. The ratio of the fluorescence intensity of the quantum dots to the metal organic framework shows an exponential growth trend with temperature.

4. The method for self-calibration temperature monitoring of a bearing based on a dual-emission fluorescent composite material according to claim 1, characterized in that: The quantum dot-metal organic framework composite material is prepared by controlling the reaction time of the quantum dots, so that the photoluminescence peak wavelength of the cadmium selenide (CdSe) quantum dots should be as far away as possible from the peak wavelength of the Eu-BTC metal organic framework material to avoid interference between the two.

5. The bearing self-calibration temperature monitoring method based on dual-emission fluorescence composite material according to claim 1 is characterized in that: The temperature calibration curve of step (1) is specifically as follows: The photoluminescence spectra of the quantum dots and metal-organic frameworks in the composite material were recorded, and the photoluminescence spectra of the two materials at different temperatures were obtained. The ratio of the spectral peak intensities corresponding to the two materials was calculated and used as the y-axis for temperature calibration. Different temperatures were used as x-values, and the recorded points were fitted to obtain the photoluminescence intensity ratio-temperature calibration curve of the quantum dot-metal-organic framework structure composite material.

6. The bearing self-calibration temperature monitoring method based on dual-emission fluorescence composite material according to claim 1 is characterized in that: The method of step (1) is to introduce the metal organic framework material as a reactor during the quantum dot synthesis process, thereby introducing the quantum dots into the pores of the metal framework to obtain the composite material. The specific method is as follows: (1) 0.4-1.2 mmol of europium nitrate hexahydrate Eu(NO3)3-6H2O 178-534 mg and 2-6 mmol of sodium acetate NaAC 164-492 mg were added to 20-60 ml of N,N-dimethylformamide (DMF) and stirred until the reaction solution was dissolved; then, 0.9-2.7 mmol of 1,3,5-benzenetricarboxylic acid H3BTC 188-564 mg was introduced into the reaction solution under continuous stirring to produce a white suspension; then, the solution was stirred for 8-24 hours, and finally, the prepared Eu-BTC metal organic framework solution was dried by centrifuge to obtain white Eu-BTC powder; (2) 40-120 mg of selenium Se powder is added to a mixture of 2-6 ml of octadecene and 0.6-1.2 ml of TOP tri-n-octylphosphine, and dissolved by ultrasonication to form a selenium precursor solution; 65-195 mg of cadmium oxide CdO is placed in a mixture of 6-10 ml of octadecene and 1-3 ml of oleic acid, and dissolved at 120-150°C to form a cadmium precursor; the temperature of the cadmium precursor solution is increased to 220-240°C, and then 100-350 mg of the prepared Eu-BTC powder is added, followed by adding 2.6-7.2 ml of selenium precursor solution in an oxygen-free environment, and the reaction is carried out for 5-30 minutes. The obtained mixed solution is collected by centrifugation and then purified by centrifugation in 10-30 ml of n-hexane to obtain a CdSe@Eu-BTC dual-emission fluorescent composite material.

7. The method for self-calibration temperature monitoring of a bearing based on a dual-emission fluorescent composite material according to claim 1, characterized in that: The step (2) of non-contact real-time measurement of the bearing rotating assembly is specifically as follows: (1) Construction of a synchronous monitoring platform: according to the different components to be tested in the bearing, the placement position of the quantum dot-metal organic framework composite material thin film sensor is adjusted; when the rotating component to be tested is the rotating inner ring of the bearing, the thin film sensor (1) is attached to the end face (2) of the inner ring; if the component to be tested is a retaining frame component, the thin film sensor (1) is placed at the end face (3) of the retaining frame, and a laser (4) is used as an excitation light source. One end of the incident optical fiber (6) is connected to the first probe (5), and the other end is connected to the laser (4). The first probe (5) is aligned with the center position of the thin film sensor (1), and the excited ultraviolet light is irradiated to the center position of the sensor through the incident optical fiber (6) and the first probe (5), so as to excite the composite material sensor to realize photoluminescence. The photoluminescence spectrum emitted by the sensor is collected by the receiving second probe (7) and the optical fiber (8), and is transmitted to the spectrometer (9). The spectral information is transmitted to the PC end (10) through the spectrometer (9); (2) Real-time temperature monitoring: For bearings in experimental or service conditions, start the synchronous monitoring platform built in step (1), compare the peak intensity ratio of CdSe quantum dots and Eu-BTC metal organic framework in the spectral information of the bearing at different times under the rotation state obtained by the PC end (10) with the photoluminescence intensity-temperature calibration curve of the thin film sensor, and obtain the real-time temperature data of the rolling bearing test assembly.

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