Micro strain sensing luminescent material and preparation method thereof
By preparing Na1.03-xTaO3:xPr3+ micro-strain luminescent materials and utilizing Pr3+ ion doping and vacancy defect modulation, the problem of insufficient detection accuracy of stress luminescent materials under low strain conditions was solved, and high-precision strain detection and visualization of complex three-dimensional structures were realized.
Patent Information
- Application Number
- CN202510789682.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-13
- Publication Date
- 2025-11-18
AI Technical Summary
Existing stress-luminescent materials lack sufficient detection accuracy under low strain conditions, making it difficult to achieve multi-angle and multi-dimensional strain detection of complex three-dimensional structures, and there is a lack of a unified theory to explain the stress-luminescence mechanism.
The micro-strain luminescent material with the chemical formula Na1.03-xTaO3:xPr3+ is used. By doping with Pr3+ ions to regulate lattice sites and vacancy defects, combined with a non-centrosymmetric structure, piezoelectricity is formed to achieve an ultra-low threshold response. The preparation method includes calcination and grinding steps.
It achieves high-precision detection of micro-strain, possesses stability and repeatability, can perform dynamic and visual strain sensing in complex three-dimensional structures, and is unaffected by electromagnetic field interference.
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Figure CN120966476A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of stress luminescent materials, in particular to a micro-strain sensing luminescent material and a preparation method thereof. BACKGROUND
[0002] As a typical representative of optical strain sensors, stress luminescent materials have potential application value due to their unique passive luminescent characteristics, good compatibility, and stable physical and chemical characteristics. In addition, it is not affected by electric and magnetic fields and can be used in various challenging environments, so it has potential application value.
[0003] However, there are still some severe challenges to obtain high-performance stress luminescent materials. For example, there are obvious differences in stress luminescent intensity, emission wavelength, repeatability, and sensitivity to stress. At present, there is still a lack of unified theory to explain the internal mechanism of stress luminescence, and the mechanism of stress luminescence still needs further development. In addition, there are few studies on the response of stress luminescent materials under low strain conditions (less than 1%), and the detection accuracy of micro-strain needs to be further improved. In the face of complex contact surfaces and irregular objects, multi-angle and multi-dimensional strain detection is still very difficult. Therefore, it is urgent to develop a three-dimensional micro-strain sensing luminescent material with high precision. SUMMARY
[0004] The present application aims to solve the above problems in the prior art and provides a micro-strain sensing luminescent material and a preparation method thereof.
[0005] The first object of the present application is to provide a micro-strain sensing luminescent material with the chemical formula Na 1.03-x TaO3:xPr 3+ , wherein 0.001≤ x≤ 0.009.
[0006] The first object of the present application is to provide a preparation method of the micro-strain sensing luminescent material as described above, and the specific steps are as follows: S1, uniformly grinding Na2CO3, Ta2O5, Pr6O 11 , and H3BO3 to obtain initial mixed raw materials; S2, placing the mixed raw materials of step S1 in an air atmosphere and calcining at a first temperature, cooling to room temperature after calcination, and uniformly grinding to obtain a precursor powder; S3, placing the precursor powder of step S2 in an air atmosphere and calcining at a second temperature, cooling to room temperature, and uniformly grinding to obtain a stress luminescent polycrystalline powder, i.e. a micro-strain sensing luminescent material; The second temperature is greater than the first temperature.
[0007] Further, in step S1, the molar ratio of Na2CO3, Ta2O5 and Pr6O 11 The molar ratio of Na, Ta and Pr is (1.03-x):1:x, wherein 0.001≤x≤0.009 Further, H3BO3 is used as a fluxing agent, and the mass of H3BO3 is 2-3% of the total mass of other raw materials.
[0008] Further, in step S2, the first temperature is 750-850 DEG C, and the calcination time is 3-5 h.
[0009] Further, in step S2, the first temperature is 800 DEG C, and the calcination time is 4 h.
[0010] Further, in step S2, the second temperature is 1050-1200 DEG C, and the calcination time is 6-9 h.
[0011] Further, in step S2, the second temperature is 1150 DEG C, and the calcination time is 8 h.
[0012] The micro-strain sensing luminescent material of the present application is doped with Pr 3+ The vacancy defects and local piezoelectricity are induced by regulating the lattice occupation of Pr ions and the formation and continuous distribution of vacancy defects, and the piezoelectricity caused by the non-centrosymmetric structure, so that the stress luminescence intensity has an ultra-low threshold response to the micro-strain.
[0013] The present application has the following advantages: (1) The NaTaO3:Pr of the present application 3+ is a new type of oxide stress luminescent material, and the preparation method is simple and the physical and chemical stability is good.
[0014] (2) The NaTaO3:Pr of the present application 3+ The thin film has linear micro-strain luminescence response performance, and the strain detection precision is as low as 100 mu st (0.01%), is not affected by electromagnetic field, and has significant stability and repeatability. Based on the special linear double-peak stress luminescence response characteristics, the whole cycle sensing of stress / strain application and release process can be realized.
[0015] (3) The present application is based on microcrystalline structure and defect analysis, and clarifies that the coupling effect of piezoelectric field and defects is the root of stress luminescence, and further promotes the mechanism research of stress luminescence.
[0016] (4) The NaTaO3:Pr of the present application 3+Stress-luminescent materials exhibit sensitive micro-strain sensing capabilities and reprocessable properties, making them suitable for three-dimensional micro-strain sensing and visualization of complex objects. Attached Figure Description
[0017] Figure 1 Na prepared in Examples 1, 2, 3, 4, and 5 1.03-x TaO3:xPr 3+ XRD patterns of stress-luminescent materials (x = 0.001, 0.003, 0.005, 0.007, 0.009); Figure 2 a and b are Na prepared in Example 3. 1.025 TaO3: 0.005Pr 3+ The stress luminescence response curves of the luminescent film under different compression and tensile micro-strains were obtained after irradiating it with 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark. Figure 2 c and d are linear relationships between luminescence intensity and applied strain. Figure 3 Preparation of Na in Example 3 1.025 TaO3: 0.005Pr 3+ The luminescent film was irradiated with 310 nm ultraviolet light for 1 min and then left in the dark for 5 min before being subjected to stress emission spectra under different compressive and tensile micro-strains on a universal testing machine; the inset shows the linear fitting results of the integrated intensity of the stress emission spectrum with the applied strain magnitude; Figure 4 Preparation of Na in Example 3 1.025 TaO3: 0.005Pr 3+ The stress luminescence curves of the luminescent film under different compression and tensile micro-strains were obtained after irradiating it with 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark. Figure 5 Preparation of Na in Example 3 1.025 TaO3: 0.005Pr 3+ The results of the stress luminescence curve of the luminescent film as a function of strain curve after irradiation with 310 nm ultraviolet light for 1 min and waiting in the dark for 5 min. Figure 6 Preparation of Na in Example 3 1.025 TaO3: 0.005Pr 3+ Results of 20 stress-luminescence cycles of the luminescent thin film under 5000 μst compressive strain and 3200 μst tensile strain; Figure 7 Preparation of Na in Example 3 1.025TaO3:0.005Pr 3+ The temperature-rising rate thermoluminescence curve and the two defect depths obtained by fitting of the luminescent material after 310 nm ultraviolet light irradiation for 1 min and waiting for 5 min in the dark environment; Figure 8 The formation energy of the defects existing in theory in NaTaO3:Pr 3+ in Example 6; Figure 9 NaTaO3:0.005Pr 1.025 TaO3:0.005Pr 3+ The stress luminescence distribution photo of the coated composite 3D structure when the loading pressure gradually increases from 0 to 500 N; Figure 10 NaTaO3:0.005Pr 1.025 TaO3:0.005Pr 3+ The stress luminescence distribution photo of the coated composite 3D structure under different maximum loading pressures (100, 300, 500 N); Figure 11 NaTaO3:0.005Pr 1.025 TaO3:0.005Pr 3+ The comparison chart of the stress luminescence and strain change curves of different regions of the coated composite 3D structure. The almost coinciding stress luminescence and strain indicate that the luminescent material has stable micro-strain response characteristics and spatial strain visualization capability. DETAILED DESCRIPTION
[0018] The following is a specific embodiment of the present application and further describes the technical solutions of the present application in combination with the drawings, but the present application is not limited to these embodiments.
[0019] Example 1 The novel high-precision micro-strain sensing luminescent material of this embodiment has a chemical formula of Na 1.029 TaO3:0.001Pr 3+ , and the preparation method thereof comprises the following steps: (1) uniformly grind high-purity Na2CO3, Ta2O5, Pr6O 11 and H3BO3 to obtain initial mixed raw materials. The molar ratio of Na, Ta and Pr is 1.029:1:0.001, and H3BO3 is 2% of the total mass of other raw materials.
[0020] (2) place the mixed raw materials of step (1) in an air atmosphere at a temperature of 800℃ for 4 h of pre-burning, cool to room temperature, and grind uniformly to obtain a precursor powder.
[0021] (3) The precursor powder of step (2) is calcined in an air atmosphere at a temperature of 1150°C for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0022] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 3.3:1, uniformly stirred, and then coated on a 30 μm thick aluminum foil by screen printing, and baked at 60°C for 4 h, and after cooling, a thin film composite material is obtained.
[0023] Pr 3+ ions are doped into a NaTaO3 matrix, and Pr 3+ serves as a luminescence center, thereby forming a fluorescent powder powder emitting orange-red light, which is compounded with optical epoxy resin to obtain an orange-red light emitting material with a micro-strain response.
[0024] The novel high-precision micro-strain sensing luminescence material of the embodiment can realize repeatable micro-strain linear response of orange-red light emission after pre-irradiation under a UV lamp.
[0025] Example 2 The novel high-precision micro-strain sensing luminescence material of the embodiment has a chemical formula of Na 1.027 TaO3:0.003Pr 3+ , and the preparation method comprises the following steps: (1) High-purity Na2CO3, Ta2O5, Pr6O 11 , and H3BO3 are ground uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Pr is 1.027:1:0.003, and H3BO3 is 2% of the total mass of the other raw materials.
[0026] (2) The mixed raw materials of step (1) are pre-fired in an air atmosphere at a temperature of 800°C for 4 h, cooled to room temperature, and ground uniformly to obtain a precursor powder.
[0027] (3) The precursor powder of step (2) is calcined in an air atmosphere at a temperature of 1150°C for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0028] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 3.3:1, uniformly stirred, and then coated on a 30 μm thick aluminum foil by screen printing, and baked at 60°C for 4 h, and after cooling, a thin film composite material is obtained.
[0029] Pr 3+ ions are doped into a NaTaO3 matrix, and Pr 3+ serves as a luminescence center, thereby forming a fluorescent powder powder emitting orange-red light, which is compounded with optical epoxy resin to obtain an orange-red light emitting material with a micro-strain response.
[0030] The new high-precision micro-strain sensing luminescent material of the embodiment can realize repeatable micro-strain linear response orange-red light emission after pre-irradiation under an ultraviolet lamp.
[0031] Embodiment 3 The new high-precision micro-strain sensing luminescent material of the embodiment has a chemical formula of Na 1.025 TaO3:0.005Pr 3+ and the preparation method comprises the following steps: (1) uniformly grinding high-purity Na2CO3, Ta2O5, Pr6O 11 and H3BO3 by a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta and Pr is 1.025:1:0.005, and H3BO3 is 2% of the total mass of the other raw materials.
[0032] (2) placing the mixed raw materials of step (1) in an air atmosphere at a temperature of 800 DEG C for pre-sintering for 4 h, cooling to room temperature, and uniformly grinding to obtain a precursor powder.
[0033] (3) placing the precursor powder of step (2) in an air atmosphere at a temperature of 1150 DEG C for calcination for 8 h, cooling to room temperature, and uniformly grinding to obtain a stress luminescence polycrystalline powder.
[0034] (4) mixing the obtained stress luminescence powder and optical epoxy resin at a mass ratio of 3.3:1, uniformly stirring, and then coating on a 30 μm thick aluminum foil by screen printing, and baking at 60 DEG C for 4 h, and then cooling to obtain a thin film composite material.
[0035] doping Pr 3+ ions into a NaTaO3 matrix, and Pr 3+ serves as a luminescent center, so that a fluorescent powder powder emitting orange-red light is formed, and the fluorescent powder powder is compounded with optical epoxy resin to obtain a micro-strain response orange-red light emitting material.
[0036] The new high-precision micro-strain sensing luminescent material of the embodiment can realize repeatable micro-strain linear response orange-red light emission after pre-irradiation under an ultraviolet lamp.
[0037] Embodiment 4 The new high-precision micro-strain sensing luminescent material of the embodiment has a chemical formula of Na 1.023 TaO3:0.007Pr 3+ and the preparation method comprises the following steps: (1) uniformly grinding high-purity Na2CO3, Ta2O5, Pr6O 11The initial mixed raw materials were obtained by grinding Na, Ta, and Pr evenly in a mortar and pestle. The molar ratio of Na, Ta, and Pr was 1.023:1:0.007, and H3BO3 accounted for 2% of the total mass of the other raw materials.
[0038] (2) The mixed raw materials from step (1) were placed in an air atmosphere at a temperature of 800°C for 4 hours, cooled to room temperature, and ground evenly to obtain precursor powder.
[0039] (3) The precursor powder from step (2) was placed in an air atmosphere and calcined at 1150°C for 8 h, cooled to room temperature, and ground uniformly to obtain stress-luminescent polycrystalline powder.
[0040] (4) The obtained stress luminescent powder and optical epoxy resin were mixed at a mass ratio of 3.3:1. After stirring evenly, the mixture was screen printed onto a 30 μm thick aluminum foil, baked at 60℃ for 4 h, and cooled to obtain a thin film composite material.
[0041] Pr 3+ Ion doping into the NaTaO3 matrix, Pr 3+ As the luminescent center, it forms a phosphor powder that emits orange-red light, which is then combined with optical epoxy resin to obtain an orange-red luminescent material with micro-strain response.
[0042] The novel high-precision micro-strain sensing luminescent material of this embodiment can achieve repeatable micro-strain linear response orange-red light emission after pre-irradiation under ultraviolet light.
[0043] Example 5 The novel high-precision micro-strain sensing luminescent material of this embodiment has the chemical formula Na. 1.021 TaO3: 0.009Pr 3+ Its preparation method includes the following steps: (1) High-purity Na2CO3, Ta2O5, and Pr6O 11 The initial mixed raw materials were obtained by grinding Na, Ta, and Pr evenly in a mortar and pestle. The molar ratio of Na, Ta, and Pr was 1.021:1:0.009, and H3BO3 accounted for 2% of the total mass of the other raw materials.
[0044] (2) The mixed raw materials from step (1) were placed in an air atmosphere at a temperature of 800°C for 4 hours, cooled to room temperature, and ground evenly to obtain precursor powder.
[0045] (3) The precursor powder from step (2) was placed in an air atmosphere and calcined at 1150°C for 8 h, cooled to room temperature, and ground uniformly to obtain stress-luminescent polycrystalline powder.
[0046] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 3.3:1, stirred uniformly, and then coated on a 30 μm thick aluminum foil by silk screen printing, and baked at 60°C for 4 h, to obtain a thin film composite material after cooling.
[0047] Pr 3+ ions are doped into the NaTaO3 matrix, Pr 3+ serves as a luminescent center, thereby forming a fluorescent powder powder emitting orange-red light, which is compounded with optical epoxy resin to obtain an orange-red light emitting material with micro-strain response.
[0048] The novel high-precision micro-strain sensing luminescent material of the embodiment can realize repeatable micro-strain linear response of orange-red light emission after pre-irradiation under an ultraviolet lamp.
[0049] Example 6 The novel high-precision micro-strain sensing luminescent material of the embodiment has a chemical formula of Na 1.025 TaO3:0.005Pr 3+ , and the preparation method comprises the following steps: (1) High-purity Na2CO3, Ta2O5, Pr6O 11 , and H3BO3 are ground uniformly in a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Pr is 1.025:1:0.005, and H3BO3 is 2% of the total mass of the other raw materials.
[0050] (2) The mixed raw materials of step (1) are pre-fired at 800°C in an air atmosphere for 4 h, cooled to room temperature, and ground uniformly to obtain a precursor powder.
[0051] (3) The precursor powder of step (2) is calcined at 1150°C in an air atmosphere for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0052] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 3.3:1, stirred uniformly, and then coated on a 30 μm thick aluminum foil by silk screen printing, and baked at 60°C for 4 h, to obtain a thin film composite material after cooling.
[0053] Na 1.025 TaO3:0.005Pr 3+ The stress luminescence material is coated and compounded with the 3D model, so as to detect the micro-strain distribution of the complex 3D structure, and the spatial distribution change of the Pr 3+ luminescence intensity visualizes the micro-strain of the detection object, and the micro-force analysis result of the complex object is obtained more simply and intuitively.
[0054] Example 7: A novel high-precision micro-strain sensing luminescent material of the formula Na 1.025 TaO3:0.005Pr 3+ , and a preparation method thereof, comprising the following steps: (1) High-purity Na2CO3, Ta2O5, Sm2O3 and H3BO3 are uniformly ground with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta and Pr is 1.025:1:0.005, and H3BO3 is 2% of the total mass of other raw materials.
[0055] (2) The mixed raw materials of step (1) are pre-fired in an air atmosphere at a temperature of 800°C for 4 h, cooled to room temperature, and uniformly ground to obtain a precursor powder.
[0056] (3) The precursor powder of step (2) is calcined in an air atmosphere at a temperature of 1150°C for 8 h, cooled to room temperature, and uniformly ground to obtain a stress luminescence polycrystalline powder.
[0057] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 1:10, uniformly stirred, then transferred to a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite round piece.
[0058] The prepared Na 1.025 TaO3:0.005Pr 3+ exhibits strong orange-red stress luminescence under a pressure of 1000 N, and the luminescence intensity shows a good linear relationship with the applied stress, proving that the composite luminescent material has potential stress sensing performance.
[0059] Comparative Example 1 A material of the formula Na 1.02 TaO3:0.01Sm 3+ is prepared; and a preparation method thereof, comprising the following steps: (1) High-purity Na2CO3, Ta2O5, Sm2O3 and H3BO3 are uniformly ground with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta and Sm is 1.02:1:0.01, and H3BO3 is 2% of the total mass of other raw materials.
[0060] (2) The mixed raw materials of step (1) are pre-fired in an air atmosphere at a temperature of 800°C for 4 h, cooled to room temperature, and uniformly ground to obtain a precursor powder.
[0061] (3) The precursor powder of step (2) is calcined in an air atmosphere at a temperature of 1150°C for 8 h, cooled to room temperature, and uniformly ground to obtain a stress luminescence polycrystalline powder.
[0062] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 1:10, stirred uniformly, and then transferred into a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite wafer.
[0063] The prepared Na 1.02 TaO3:0.01Sm 3+ The epoxy resin wafer does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0064] Comparative Example 2 The material of formula Na 1.02 TaO3:0.01Tm 3+ is prepared by the following steps: (1) High-purity Na2CO3, Ta2O5, Tm2O3, and H3BO3 are ground uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Tm is 1.02:1:0.01, and H3BO3 is 2% of the total mass of the other raw materials.
[0065] (2) The mixed raw materials of step (1) are pre-fired in an air atmosphere at a temperature of 800°C for 4 h, cooled to room temperature, and ground uniformly to obtain a precursor powder.
[0066] (3) The precursor powder of step (2) is calcined in an air atmosphere at a temperature of 1150°C for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0067] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 1:10, stirred uniformly, and then transferred into a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite wafer.
[0068] The prepared Na 1.02 TaO3:0.01Tm 3+ The epoxy resin wafer does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0069] Comparative Example 3 The material of formula Na 1.02 TaO3:0.01Dy 3+ is prepared by the following steps: (1) High-purity Na2CO3, Ta2O5, Dy2O3, and H3BO3 are ground uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Dy is 1.02:1:0.01, and H3BO3 is 2% of the total mass of the other raw materials.
[0070] (2) Put the mixed raw materials of step (1) into an air atmosphere at a temperature of 800°C and pre-burn for 4 h, cool to room temperature, and grind uniformly to obtain a precursor powder.
[0071] (3) Put the precursor powder of step (2) into an air atmosphere at a temperature of 1150°C and bake for 8 h, cool to room temperature, and grind uniformly to obtain a stress luminescence polycrystal powder.
[0072] (4) Mix the obtained stress luminescence powder with optical epoxy resin at a mass ratio of 1:10, stir uniformly, then transfer to a mold, bake at 60°C for 4 h, and cool to obtain an epoxy resin composite wafer.
[0073] The prepared Na 1.02 TaO3:0.01Dy 3+ The epoxy resin wafer does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0074] Comparative Example 4 A material with a chemical formula of Na 1.02 TaO3:0.01Eu 3+ was prepared; the preparation method comprises the following steps: (1) Grind high-purity Na2CO3, Ta2O5, Eu2O3, and H3BO3 uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Eu is 1.02:1:0.01, and H3BO3 is 2% of the total mass of the other raw materials.
[0075] (2) Put the mixed raw materials of step (1) into an air atmosphere at a temperature of 800°C and pre-burn for 4 h, cool to room temperature, and grind uniformly to obtain a precursor powder.
[0076] (3) Put the precursor powder of step (2) into an air atmosphere at a temperature of 1150°C and bake for 8 h, cool to room temperature, and grind uniformly to obtain a stress luminescence polycrystal powder.
[0077] (4) Mix the obtained stress luminescence powder with optical epoxy resin at a mass ratio of 1:10, stir uniformly, then transfer to a mold, bake at 60°C for 4 h, and cool to obtain an epoxy resin composite wafer.
[0078] The prepared Na 1.02 TaO3:0.01Eu 3+ The epoxy resin wafer does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0079] Comparative Example 5 A material with the chemical formula of Na 1.02 TaO3:0.01Tb 3+ was prepared. The preparation method comprises the following steps: (1) High purity Na2CO3, Ta2O5, Tb4O7 and H3BO3 were ground uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta and Tb was 1.02:1:0.01, and H3BO3 was 2% of the total mass of other raw materials.
[0080] (2) The mixed raw materials of step (1) were pre-fired at 800°C in an air atmosphere for 4 h, cooled to room temperature, and ground uniformly to obtain a precursor powder.
[0081] (3) The precursor powder of step (2) was calcined at 1150°C in an air atmosphere for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0082] (4) The obtained stress luminescence powder was mixed with optical epoxy resin at a mass ratio of 1:10, stirred uniformly, then transferred to a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite round piece.
[0083] A material with the chemical formula of Na 1.02 TaO3:0.01Tb 3+ The epoxy resin round piece did not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doped stress luminescence.
[0084] Comparative Example 6 A material with the chemical formula of Na 1.02 TaO3:0.01Er 3+ was prepared. The preparation method comprises the following steps: (1) High purity Na2CO3, Ta2O5, Er2O3 and H3BO3 were ground uniformly with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta and Er was 1.02:1:0.01, and H3BO3 was 2% of the total mass of other raw materials.
[0085] (2) The mixed raw materials of step (1) were pre-fired at 800°C in an air atmosphere for 4 h, cooled to room temperature, and ground uniformly to obtain a precursor powder.
[0086] (3) The precursor powder of step (2) was calcined at 1150°C in an air atmosphere for 8 h, cooled to room temperature, and ground uniformly to obtain a stress luminescence polycrystalline powder.
[0087] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 1:10, stirred uniformly, and then transferred into a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite round sheet.
[0088] The prepared Na 1.02 TaO3:0.01Er 3+ The epoxy resin round sheet does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0089] Comparative Example 7 The prepared material has a chemical formula of Na 1.02 TaO3:0.01Yb 3+ The preparation method comprises the following steps: (1) High-purity Na2CO3, Ta2O5, Yb2O3, and H3BO3 are uniformly ground with a mortar to obtain initial mixed raw materials. The molar ratio of Na, Ta, and Yb is 1.02:1:0.01, and H3BO3 is 2% of the total mass of the other raw materials.
[0090] (2) The mixed raw materials of step (1) are pre-fired at a temperature of 800°C for 4 h in an air atmosphere, cooled to room temperature, and uniformly ground to obtain a precursor powder.
[0091] (3) The precursor powder of step (2) is calcined at a temperature of 1150°C for 8 h in an air atmosphere, cooled to room temperature, and uniformly ground to obtain a stress luminescence polycrystalline powder.
[0092] (4) The obtained stress luminescence powder is mixed with optical epoxy resin at a mass ratio of 1:10, stirred uniformly, and then transferred into a mold, baked at 60°C for 4 h, and cooled to obtain an epoxy resin composite round sheet.
[0093] The prepared Na 1.02 TaO3:0.01Yb 3+ The epoxy resin round sheet does not exhibit stress luminescence under a pressure of 1000 N, proving that the NaTaO3 matrix is only suitable for Pr 3+ doping to achieve stress luminescence.
[0094] Figure 1 The XRD patterns of the stress luminescence materials Na 1.03-x TaO3:xPr 3+ (x = 0.001, 0.003, 0.005, 0.007, 0.009) prepared in Examples 1, 2, 3, 4, and 5. By comparing them with the standard card ICSD#150430, it is proved that the synthesized fluorescent powder is a pure phase, and Pr 3+Doping does not change the crystal structure of the material.
[0095] Figure 2 a, b are Na 1.025 TaO3:0.005Pr 3+ The stress luminescence response curves of the luminescent film under different compression and tensile micro-strain applied on the universal testing machine after irradiation of 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark environment. It can be clearly seen that the stress luminescence intensity increases with the increase of the applied micro-strain, and the luminescence intensity is linearly related to the applied strain size Figure 2 c, d), which proves that the luminescent film has excellent micro-strain sensing ability.
[0096] Figure 3 a, b are Na 1.025 TaO3:0.005Pr 3+ The stress luminescence spectra of the luminescent film under different compression and tensile micro-strain applied on the universal testing machine after irradiation of 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark environment, and the linear fitting results of the stress luminescence spectrum integral intensity and the applied strain size are shown in the insert.
[0097] Figure 4 a, b are Na 1.025 TaO3:0.005Pr 3+ The stress luminescence curves of the luminescent film under different compression and tensile micro-strain applied on the universal testing machine after irradiation of 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark environment, and the results show that the detection limit of the material to micro-strain can reach 100 μst (0.01%).
[0098] Figure 5 a, b are Na 1.025 TaO3:0.005Pr 3+ The results of the stress luminescence curves of the luminescent film after irradiation of 310 nm ultraviolet light for 1 min and waiting for 5 min in the dark environment. Obviously, the film shows regular luminescence response to the gradual increase and decay of strain, which proves its ability to sense the whole process of strain application and release.
[0099] Figure 6 a, b are Na 1.025 TaO3:0.005Pr 3+The luminescent film was tested for 20 stress luminescence cycles under 5000 μs compressive strain and 3200 μs tensile strain, respectively. Each test required 310 nm ultraviolet light irradiation for 1 min, and the sample was kept in the dark for 5 min. Significant stress luminescence signals were still detected after multiple cycle tests, indicating that the material of the application has good stability and repeatability.
[0100] Figure 7 NaTaO3:0.005Pr was prepared for Example 3 1.025 TaO3:0.005Pr 3+ The temperature rising rate thermoluminescence curve of the luminescent material after 310 nm ultraviolet light irradiation for 1 min and keeping in the dark for 5 min, and the two defect depths obtained by fitting.
[0101] Figure 8 The formation energy of the defects existing in NaTaO3:Pr 3+ was calculated by using density functional theory (DFT), and the promoting effect of the defects on stress luminescence was explained.
[0102] Figure 9 NaTaO3:0.005Pr was prepared for Example 6 1.025 TaO3:0.005Pr 3+ The stress luminescence distribution photo of the coated composite 3D structure when the loading pressure gradually increased from 0 to 500 N. The gradually enhanced stress luminescence indicates the sensitive sensing ability and spatial visualization ability of the luminescent material to the internal micro-strain of the complex structure.
[0103] Figure 10 NaTaO3:0.005Pr was prepared for Example 6 1.025 TaO3:0.005Pr 3+ The stress luminescence distribution photo of the coated composite 3D structure under different maximum loading pressures (100, 300, 500 N).
[0104] Figure 11 NaTaO3:0.005Pr was prepared for Example 6 1.025 TaO3:0.005Pr 3+ The stress luminescence and strain change curve comparison chart of different regions of the coated composite 3D structure. The almost coinciding stress luminescence and strain indicate the stable micro-strain response characteristics and spatial strain visualization ability of the luminescent material.
[0105] The above matters not covered are applicable to the prior art.
[0106] Although some specific embodiments of the present application have been described in detail by way of example with reference to the drawings, it is to be understood that the above examples are intended to be illustrative only and are not intended to limit the scope of the present application, and that various modifications and changes can be made by those skilled in the art to the particular embodiments described without departing from the spirit and scope of the present application. It is intended that the scope of the present application be limited only by the broadest interpretation of the appended claims to be accorded under 35 U.S.C. § 112.
Claims
1. A micro-strain sensing luminescent material, characterized in that, The chemical formula is Na 1.03-x TaO3:xPr 3+ , where 0.001 ≤ x ≤ 0.
009.
2. A method for preparing the micro-strain sensing luminescent material as described in claim 1, characterized in that, The specific steps are as follows: S1, Na2CO3, Ta2O5, Pr6O 11 The initial mixed raw materials were obtained by grinding H3BO3 evenly. S2. Place the mixed raw materials from step S1 in an air atmosphere and calcine at a first temperature. After calcination, cool to room temperature and grind evenly to obtain precursor powder. S3. Place the precursor powder from step S2 in an air atmosphere and calcine it at a second temperature. Cool it to room temperature and grind it evenly to obtain stress-luminescent polycrystalline powder, i.e., micro-strain sensing luminescent material. The second temperature is greater than the first temperature.
3. The preparation method according to claim 2, characterized in that, In step S1, Na2CO3, Ta2O5 and Pr6O 11 The molar ratio of Na, Ta, and Pr is (1.03-x):1:x, where 0.001 ≤ x ≤ 0.
009.
4. The preparation method according to claim 2, characterized in that, H3BO3 is used as a flux, and its mass is 2-3% of the total mass of other raw materials.
5. The preparation method according to claim 2, characterized in that, In step S2, the first temperature is 750-850℃, and the roasting time is 3-5 h.
6. The preparation method according to claim 2, characterized in that, In step S2, the first temperature is 800℃, and the roasting time is 4 h.
7. The preparation method according to claim 2, characterized in that, In step S2, the second temperature is 1050-1200℃, and the calcination time is 6-9 h.
8. The preparation method according to claim 2, characterized in that, In step S2, the second temperature is 1150℃, and the calcination time is 8 h.