Composite wafer narrow pulse stress sensor and preparation method thereof

Abstract

The invention discloses a composite wafer narrow pulse stress sensor and a preparation method thereof, the composite wafer narrow pulse stress sensor comprises a piezoelectric body, a silver electrode and a ceramic protection layer, the piezoelectric body comprises a plurality of piezoelectric microcolumns and an organic silicon resin matrix, the plurality of piezoelectric microcolumns are distributed in the organic silicon resin matrix at intervals, and the piezoelectric microcolumns are arranged in the organic silicon resin matrix. The organic silicon resin matrix comprises silicon carbide powder and methyl phenyl silicone resin, the silver electrodes are arranged on the two opposite sides of the piezoelectric body in the first direction, and the ceramic protection layer is located on the sides, away from the piezoelectric body, of the silver electrodes in the first direction. According to the composite wafer narrow pulse stress sensor provided by the embodiment of the invention, the composite wafer narrow pulse stress sensor can easily excite a narrow pulse signal, so that the difficulty of processing an ultrasonic signal excited by the composite wafer narrow pulse stress sensor by a subsequent processing module can be effectively reduced; and the precision of the stress measured according to the ultrasonic signal excited by the composite wafer narrow pulse stress sensor can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nondestructive testing, in particular to a narrow pulse stress sensor for composite wafer and a preparation method thereof. BACKGROUND

[0002] High-strength bolt connection is an important assembly method in wind turbine assembly, and is an important connection form of blade root, variable pitch bearing, tower, foundation ring and other parts. The number of high-strength bolts used in a wind turbine exceeds 1000, and the working safety and reliability of high-strength bolts will directly affect the safe, reliable and economic operation of the wind turbine.

[0003] High-strength bolts of wind turbines are mainly used in key parts such as blade roots and towers, and play a role in connection and transmission of force and torque. They are prone to fatigue fracture under long-term alternating loads during use, resulting in unplanned shutdown. In recent years, with the rapid increase in the number of wind turbines installed in China, accidents of wind turbine collapse caused by connection bolt failure have occurred from time to time. For example, the bolt failure caused the flange plate of the entire tower to bend and deform, and in serious cases, the wind turbine tower collapsed, causing serious economic losses and social impact. The failure of wind turbine bolts is characterized by fatigue. The main reason for bolt fatigue cracks is that the pre-tightening force of the bolts is inconsistent during installation, and the pre-tightening force is prone to decrease due to loosening during service. After the bolts loosen, they will bear alternating bending loads, causing fatigue cracks to occur at stress concentration positions (such as thread roots), and the fatigue cracks will continue to expand under alternating loads until the final instability and fracture. In addition, the presence of corrosive media can also accelerate the expansion of fatigue cracks. Therefore, bolt stress variation is the most important indicator of bolt safety. Precise measurement of bolt stress and monitoring of stress data throughout the life cycle of the bolt are of great significance to the design and safe use of wind turbine bolt connection structures.

[0004] Ultrasonic testing is one of the most widely used methods for detecting bolt pre-tightening force. Due to the good penetration ability of ultrasonic waves, it has the advantages of fast measurement, non-destructive testing, no harm to human body, energy saving and environmental protection, and wide application range. In recent years, it has been widely used in the fields of construction, aviation, shipping, medical equipment and machinery. Ultrasonic stress measurement is mainly based on the acoustic elasticity phenomenon, that is, the propagation speed of sound waves in an elastic medium will change due to the change of stress in the medium. A method for determining stress by measuring the propagation speed of ultrasonic waves is proposed. Many scholars have carried out related research on the application of acoustic elasticity effect, and the application of acoustic elasticity effect theory has been continuously improved. The technology of measuring bolt stress using ultrasonic waves has also begun to develop.

[0005] With the gradual development of the bolt stress measurement technology using ultrasonic waves, the related supporting technologies are also constantly improved, and the selection of the stress sensor is one of the key links. Among the stress sensors, piezoelectric ceramic blocks are often selected. Pure piezoelectric ceramic materials mainly include titanate (barium titanate) and lead-containing compounds (lead zirconate titanate, lead metaniobate, etc.). Among them, the lead zirconate titanate series of piezoelectric ceramics (PZT ceramics) have the advantages of high Curie point, piezoelectric constant, electromechanical coupling coefficient, etc.

[0006] However, pure piezoelectric ceramics are used as sensitive elements. Since the acoustic impedance of the piezoelectric ceramic block is large, the matching with water and biological tissues is poor, and the density of the piezoelectric ceramic block is high and the brittleness is large, the piezoelectric ceramic block is prone to breakage and fracture during mechanical vibration. It is not suitable to use a large area in the array of the transducer. In addition, the transverse coupling of the piezoelectric ceramic block is large, and the thickness vibration mode is complex, so that the vibration mode of the PZT piezoelectric wafer in the related technology is complex, the excited ultrasonic wave signal is complex, and it is not conducive to high-precision stress measurement. Therefore, how to make the ultrasonic wave signal excited by the stress sensor simple so as to facilitate high-precision stress measurement has become a technical problem to be solved. SUMMARY

[0007] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a composite wafer narrow pulse stress sensor. The ultrasonic wave excited by the composite wafer narrow pulse stress sensor is a narrow pulse signal. Since the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal by the subsequent processing module is effectively reduced, and the accuracy of the stress measured according to the ultrasonic wave signal is also improved.

[0008] The present application also provides a preparation method of the composite wafer narrow pulse stress sensor.

[0009] The composite wafer narrow pulse stress sensor according to the first aspect of the present application comprises: a piezoelectric body, the piezoelectric body comprising a piezoelectric microcolumn and an organic silicone resin matrix, the piezoelectric microcolumn being a plurality of piezoelectric microcolumns, the plurality of piezoelectric microcolumns being spaced apart in the organic silicone resin matrix, the organic silicone resin matrix comprising silicon carbide powder and methylphenyl silicone resin; a silver electrode, provided on opposite sides of the piezoelectric body in a first direction; and a ceramic protective layer, the ceramic protective layer being located on the side of the silver electrode away from the piezoelectric body along the first direction.

[0010] According to the composite wafer narrow pulse stress sensor provided by the embodiment of the present application, by spacing distributing a plurality of piezoelectric micro columns in the organic silicon resin matrix, the organic silicon resin matrix can reduce the dielectric constant of the piezoelectric body, improve the hydrostatic piezoelectric constant of the piezoelectric body, and make the composite wafer narrow pulse stress sensor more easily excite a narrow pulse signal. Since the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor in the subsequent processing module can be effectively reduced, and the accuracy of the stress measured by the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor is improved.

[0011] According to some embodiments of the present application, the thickness dimension of the piezoelectric micro column in the first direction is 0.1mm-2mm; and / or, the cross-sectional area of the piezoelectric micro column is 1mm 2 -25mm 2 , the cross section of the piezoelectric micro column is perpendicular to the first direction.

[0012] According to some embodiments of the present application, a plurality of piezoelectric micro columns are arranged in the same plane perpendicular to the first direction; and / or, the distance between two adjacent piezoelectric micro columns is 0.1mm-2mm.

[0013] According to some embodiments of the present application, the deposition thickness of the silver electrode on one side in the first direction is 10μm-50μm.

[0014] According to some embodiments of the present application, the particle size of the silicon carbide powder is 100nm-800nm; and / or, the thickness dimension of the ceramic protective layer in the first direction is 0.1mm-0.5mm.

[0015] The preparation method of the composite wafer narrow pulse stress sensor according to the second aspect of the embodiment of the present application is the composite wafer narrow pulse stress sensor according to the first aspect of the embodiment described above, and includes the following steps:

[0016] Preparation of the piezoelectric body;

[0017] Plating the silver electrode on the opposite sides of the piezoelectric body along the first direction;

[0018] The ceramic protective layer is arranged on the side of the silver electrode away from the piezoelectric body along the first direction, and the composite wafer narrow pulse stress sensor is prepared;

[0019] In which, the piezoelectric material block is cut by laser cutting method to prepare a plurality of piezoelectric micro columns;

[0020] The organic silicon resin is used to bond and fix a plurality of piezoelectric micro columns to prepare the piezoelectric base body.

[0021] According to the preparation method of the composite wafer narrow pulse stress sensor, the multiple piezoelectric micro columns are distributed in the silicone resin matrix, the silicone resin matrix supports and fixes the multiple piezoelectric micro columns, the dielectric constant of the piezoelectric body is reduced, the hydrostatic piezoelectric constant of the piezoelectric body is improved, the composite wafer narrow pulse stress sensor is easy to excite a narrow pulse signal, the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor in a subsequent processing module is effectively reduced, and the accuracy of the stress measured according to the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor is improved.

[0022] According to some embodiments of the present application, the piezoelectric material block is cut by a laser cutting method to obtain multiple piezoelectric micro columns, including:

[0023] The piezoelectric material block is placed on a water-cooled base for laser cutting, the laser cutting power is 100-200 W, and the laser cutting speed is 1-5 mm / min, to obtain multiple piezoelectric micro columns;

[0024] The multiple piezoelectric micro columns are bonded and fixed by a silicone resin to obtain the piezoelectric body, including:

[0025] The silicon carbide powder is stirred with methylphenyl silicone resin to obtain the silicone resin;

[0026] The silicone resin is poured into the multiple piezoelectric micro columns, and the piezoelectric body is obtained after curing.

[0027] According to some embodiments of the present application, the silver electrode is plated on the opposite sides of the piezoelectric body along the first direction, including:

[0028] The opposite sides of the piezoelectric body along the first direction are double polished;

[0029] The polished piezoelectric body is placed in a vacuum chamber, and an electrode material is plated on the opposite sides of the piezoelectric body along the first direction by a radio frequency magnetron sputtering method, to plate the silver electrode on the opposite sides of the piezoelectric body along the first direction;

[0030] The surface roughness Ra of the polished piezoelectric body is less than 0.4 μm;

[0031] In the radio frequency magnetron sputtering method, the sputtering power is 500-1000 W;

[0032] The purity of silver in the electrode material is greater than 99.5%.

[0033] According to some embodiments of the present application, the piezoelectric body is double-side polished along the surfaces on opposite sides of the first direction, comprising:

[0034] The piezoelectric body is double-side polished along the surfaces on opposite sides of the first direction by using silicon carbide sandpaper, and the thickness removed from the piezoelectric body in the first direction is less than 0.05mm;

[0035] The mesh number of the silicon carbide sandpaper is 200-1200.

[0036] According to some embodiments of the present application, the ceramic protective layer is arranged on the side of the silver electrode facing away from the piezoelectric body along the first direction, and a narrow pulse stress sensor is prepared, comprising:

[0037] The ceramic protective layer is fixed on the side of the silver electrode facing away from the piezoelectric body along the first direction by using an acrylate welding adhesive layer, and the narrow pulse stress sensor is prepared by curing for 30-60min at room temperature.

[0038] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0039] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the accompanying drawings, wherein:

[0040] Figure 1 is an assembly schematic diagram of a composite wafer narrow pulse stress sensor and a wind power bolt according to some embodiments of the present application;

[0041] Figure 2 is Figure 1 is a schematic diagram of a piezoelectric body in a composite wafer narrow pulse stress sensor in

[0042] Figure 3 is an ultrasonic waveform diagram excited by a composite wafer narrow pulse stress sensor according to some embodiments of the present application;

[0043] Figure 4 is an ultrasonic waveform diagram excited by a stress sensor in the related art.

[0044] REFERENCE NUMERALS:

[0045] 100, composite wafer narrow pulse stress sensor;

[0046] 1, ceramic protective layer; 2, piezoelectric body; 21, piezoelectric micro-column; 22, silicone resin matrix; 3, silver electrode;

[0047] 200, wind power bolt; 4, epoxy resin adhesive layer. DETAILED DESCRIPTION

[0048] Embodiments of the present application are described below in detail with reference to the accompanying drawings, wherein the same or similar notations used throughout the drawings and the detailed description denote the same or similar elements or elements having the same or similar functions. The embodiments described below by reference to the drawings are exemplary only, and are used only for the purpose of explaining the present application, and should not be understood as limiting the present application.

[0049] Reference is made below Figures 1-4 A composite wafer narrow pulse stress sensor 100 according to an embodiment of the present application is described below.

[0050] Reference is made below Figures 1-2 The composite wafer narrow pulse stress sensor 100 according to the first embodiment of the first aspect of the present application comprises a piezoelectric body 2, a silver electrode 3 and a ceramic protective layer 1. The piezoelectric body 2 comprises a plurality of piezoelectric micro pillars 21 and an organic silicone resin matrix 22. The plurality of piezoelectric micro pillars 21 are spaced apart in the organic silicone resin matrix 22. The organic silicone resin matrix 22 comprises silicon carbide powder and methyl phenyl silicone resin. The silver electrode 3 is arranged on opposite sides of the piezoelectric body 2 in a first direction (for example, the e1 direction in FIG. 1). The ceramic protective layer 1 is arranged on the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction. Figure 1 The silver electrode 3 is arranged on opposite sides of the piezoelectric body 2 in the first direction to apply a voltage to the piezoelectric body 2, so that the piezoelectric body 2 vibrates to excite ultrasonic waves. The ceramic protective layer 1 can protect the piezoelectric body 2 and the silver electrode 3, reduce the possibility of corrosion of the piezoelectric body 2 and the silver electrode 3 due to exposure to the external environment, and improve the surface wear and impact resistance of the composite wafer narrow pulse stress sensor 100, thereby prolonging the service life of the composite wafer narrow pulse stress sensor 100 as a whole. By including silicon carbide powder in the organic silicone resin matrix 22, the oxidation time of the methyl phenyl silicone resin can be slowed down, and the anti-aging performance of the organic silicone resin matrix 22 can be enhanced.

[0051] By arranging a plurality of piezoelectric micro pillars 21 spaced apart in the organic silicone resin matrix 22, the organic silicone resin matrix 22 can support and fix the plurality of piezoelectric micro pillars 21 while reducing the dielectric constant of the piezoelectric body 2 as a whole and improving the hydrostatic piezoelectric constant of the piezoelectric body 2. This makes it easier for the composite wafer narrow pulse stress sensor 100 to excite narrow pulse signals. Since the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 in the processing module can be effectively reduced, and the accuracy of the stress measured by the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 can be improved.

[0052] By arranging a plurality of piezoelectric micro pillars 21 spaced apart in the organic silicone resin matrix 22, the organic silicone resin matrix 22 can support and fix the plurality of piezoelectric micro pillars 21 while reducing the dielectric constant of the piezoelectric body 2 as a whole and improving the hydrostatic piezoelectric constant of the piezoelectric body 2. This makes it easier for the composite wafer narrow pulse stress sensor 100 to excite narrow pulse signals. Since the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 in the processing module can be effectively reduced, and the accuracy of the stress measured by the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 can be improved.

[0053] For example, when the composite wafer narrow pulse stress sensor 100 is applied to the wind power bolt 200, the silver electrode 3 is arranged on the opposite sides of the piezoelectric body 2 in the first direction to apply a voltage to the piezoelectric body 2, so that the piezoelectric body 2 vibrates to excite ultrasonic waves, the excited ultrasonic waves propagate inside the wind power bolt 200, and the stress borne by the wind power bolt 200 is measured by measuring the propagation time of the ultrasonic waves inside the wind power bolt 200 and the ultrasonic wave curve. Since the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 is a narrow pulse signal, the positions of the peaks and troughs of the ultrasonic wave signal can be more accurately measured, and the waveform is relatively simple, so that the accuracy and sensitivity of the measured stress borne by the wind power bolt 200 can be improved.

[0054] For example, when the composite wafer narrow pulse stress sensor 100 is applied to the wind power bolt 200, the epoxy adhesive layer 4 can be used to paste and fix the composite wafer narrow pulse stress sensor 100 on the wind power bolt 200, so that the connection between the composite wafer narrow pulse stress sensor 100 and the wind power bolt 200 is simple and has strong connection strength, and the possibility of the composite wafer narrow pulse stress sensor 100 falling off the wind power bolt 200 due to external force impact or vibration is reduced.

[0055] For example, the piezoelectric micro-column 21 is a PN material, which has high high-temperature resistance, so that the piezoelectric micro-column 21 has good thermoelectric performance, and the possibility of phase change or performance degradation of the piezoelectric micro-column 21 when heated is reduced or prevented.

[0056] In the description of the present application, the meaning of "a plurality of" is two or more.

[0057] According to the composite wafer narrow pulse stress sensor 100 of the embodiment of the present application, the plurality of piezoelectric micro-columns 21 are spaced apart in the silicone resin matrix 22, the silicone resin matrix 22 can reduce the dielectric constant of the piezoelectric body 2 and improve the hydrostatic piezoelectric constant of the piezoelectric body 2 while playing a supporting and fixing role for the plurality of piezoelectric micro-columns 21, so that the composite wafer narrow pulse stress sensor 100 is more likely to excite a narrow pulse signal. Since the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 by the subsequent processing module can be effectively reduced, and the accuracy of the stress measured according to the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 can be improved.

[0058] Reference Figures 1-2According to some embodiments of the present application, the thickness dimension t of the piezoelectric micro pillar 21 in the first direction is 0.1mm-2mm. For example, the thickness dimension t of the piezoelectric micro pillar 21 in the first direction can be 0.1mm, 0.8mm, 1.4mm, 1.7mm, 2mm, etc. By setting the thickness dimension t of the piezoelectric micro pillar 21 in the first direction to be 0.1mm-2mm, the piezoelectric micro pillar 21 can have a strong structural strength and be easy to manufacture.

[0059] With reference to Figures 1-2 According to some embodiments of the present application, the cross-sectional area of the piezoelectric micro pillar 21 is 1mm 2 -25mm 2 The cross section of the piezoelectric micro pillar 21 is perpendicular to the first direction. For example, the cross-sectional area of the piezoelectric micro pillar 21 can be 1mm 2 , 8mm 2 , 15mm 2 , 20mm 2 , 25mm 2 , etc. By setting the cross-sectional area of the piezoelectric micro pillar 21 to be 1mm 2 -25mm 2 , the number of piezoelectric micro pillars 21 can be as large as possible when the total cross-sectional area of the piezoelectric body 2 is constant, and the vibration of the plurality of piezoelectric micro pillars 21 in the first direction can be enhanced by energy superposition to enhance the vibration of the piezoelectric body 2 in the first direction, effectively improving the piezoelectric strain constant D 33 of the piezoelectric body 2 as a whole, so that the composite wafer narrow pulse stress sensor 100 is more likely to excite a narrow pulse signal.

[0060] For example, the piezoelectric micro pillar 21 can be a cuboid, which can facilitate batch manufacturing of the piezoelectric micro pillar 21 and improve the manufacturing efficiency of the piezoelectric micro pillar 21.

[0061] With reference to Figures 1-2 According to some embodiments of the present application, the plurality of piezoelectric micro pillars 21 are arranged at intervals in the same plane perpendicular to the first direction, which can enhance the vibration of the piezoelectric body 2 in the first direction as a whole, reduce or prevent the possibility of vibration of the piezoelectric body 2 in other directions, so that the piezoelectric strain constant D33 of the piezoelectric body 2 as a whole can be improved, and the composite wafer narrow pulse stress sensor 100 is more likely to excite a narrow pulse signal.

[0062] With reference to Figures 1-2According to some embodiments of the present application, the interval w between two adjacent piezoelectric micro pillars 21 is 0.1mm-2mm. For example, the interval w between two adjacent piezoelectric micro pillars 21 can be 0.1mm, 0.8mm, 1.4mm, 1.7mm, 2mm, etc. By setting the interval w between two adjacent piezoelectric micro pillars 21 to be 0.1mm-2mm, the interval w between two adjacent piezoelectric micro pillars 21 is moderate, so that the vibration frequencies of two adjacent piezoelectric micro pillars 21 can be relatively close or even consistent, thereby facilitating the simple and stable ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 and reducing the possibility of exciting stray ultrasonic waves.

[0063] With reference to Figures 1-2 According to some embodiments of the present application, the deposition thickness h of the single-sided silver electrode 3 in the first direction is 10-50μm. For example, the deposition thickness h of the single-sided silver electrode 3 in the first direction can be 10μm, 25μm, 35μm, 40μm, 50μm, etc. By setting the deposition thickness h of the single-sided silver electrode 3 in the first direction to be 10-50μm, the thickness of the single-sided silver electrode 3 can be relatively large, so that the intensity of the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 is relatively high, thereby facilitating the timely and accurate extraction of the ultrasonic wave signal by the subsequent processing module, and the preparation of the silver electrode 3 can also be completed in a relatively short time, avoiding the situation that the preparation time of the silver electrode 3 is too long due to the excessively large thickness of the single-sided silver electrode 3, and facilitating the improvement of the preparation efficiency of the silver electrode 3.

[0064] With reference to Figures 1-2 According to some embodiments of the present application, the particle size of the silicon carbide powder is 100-800nm. For example, the particle size of the silicon carbide powder can be 100nm, 300nm, 500nm, 700nm, 800nm, etc.

[0065] By setting the particle size of the silicon carbide powder to be not less than 100nm, the silicon carbide powder can be better combined with the methylphenyl silicone resin to form the organic silicone resin matrix 22, thereby reducing or avoiding the agglomeration phenomenon caused by the excessively small particle size of the silicon carbide powder, and reducing the possibility of the excessively low continuity of the formed organic silicone resin matrix 22, thereby avoiding the situation that the organic silicone resin matrix 22 is prone to breakage due to the excessively low continuity of the organic silicone resin matrix 22, so that the overall structure of the formed organic silicone resin matrix 22 is relatively stable.

[0066] With reference to Figures 1-2 According to some embodiments of the present application, the thickness dimension g of the ceramic protective layer 1 in the first direction is 0.1mm-0.5mm. For example, the thickness dimension g of the ceramic protective layer 1 in the first direction can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

[0067] The thickness dimension g of the ceramic protective layer 1 in the first direction is 0.1mm-0.5mm, so that the ceramic protective layer 1 has strong impact resistance, can effectively resist external impact force, avoid damage to the internal piezoelectric body 2 or silver electrode 3, and also make the ultrasonic wave excited by the composite wafer narrow pulse stress sensor 100 pass through the ceramic protective layer 1 more smoothly, reducing the attenuation of the ultrasonic wave in the ceramic protective layer 1.

[0068] Referring to Figures 1-2 According to the preparation method of the composite wafer narrow pulse stress sensor 100 according to the second aspect of the present application, the composite wafer narrow pulse stress sensor 100 is according to the composite wafer narrow pulse stress sensor 100 of the first aspect of the application, comprising the following steps:

[0069] Preparation of the piezoelectric body 2;

[0070] Silver electrodes 3 are plated on the opposite sides of the piezoelectric body 2 along the first direction;

[0071] The ceramic protective layer 1 is arranged on the side of the silver electrode 3 away from the piezoelectric body 2 along the first direction, and the composite wafer narrow pulse stress sensor 100 is prepared;

[0072] The piezoelectric material block is cut by laser cutting method to obtain a plurality of piezoelectric micro columns 21, compared with cutting the piezoelectric material block by diamond blade, laser cutting can improve the cutting efficiency of the piezoelectric material block, and can cut any size and any shape, which can better meet the different size requirements;

[0073] The plurality of piezoelectric micro columns 21 are bonded and fixed by organic silicone resin to obtain a piezoelectric blank, which can make the connection between the plurality of piezoelectric micro columns 21 simple and have strong stability.

[0074] According to the preparation method of the composite wafer narrow pulse stress sensor 100 according to the embodiment of the present application, the plurality of piezoelectric micro columns 21 are distributed in the organic silicone resin matrix 22, the organic silicone resin matrix 22 can reduce the dielectric constant of the piezoelectric body 2 while supporting and fixing the plurality of piezoelectric micro columns 21, improve the hydrostatic piezoelectric constant of the piezoelectric body 2, and make the composite wafer narrow pulse stress sensor 100 more easily excite narrow pulse signals. Because the tail wave of the narrow pulse signal is short and the waveform is simple, the difficulty of processing the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 in the subsequent processing module can be effectively reduced, and the accuracy of the stress measured by the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 is also improved.

[0075] Referring to Figures 1-2 According to some embodiments of the present application, the piezoelectric material block is cut by laser cutting method to obtain a plurality of piezoelectric micro columns 21, comprising:

[0076] The piezoelectric material block is placed on a water-cooled base for laser cutting, the laser cutting power is 100-200 watts, and the laser cutting speed is 1-5 mm / min, to obtain a plurality of piezoelectric micro pillars 21;

[0077] The plurality of piezoelectric micro pillars 21 are bonded and fixed by using an organic silicon resin to obtain a piezoelectric body 2, comprising:

[0078] The silicon carbide powder is stirred with methylphenyl silicone resin to obtain an organic silicon resin;

[0079] The organic silicon resin is poured into the plurality of piezoelectric micro pillars 21, and after curing, the piezoelectric body 2 is obtained, and the organic silicon resin is cured to form an organic silicon resin base 22.

[0080] Due to the high temperature during laser cutting, the piezoelectric material block is placed on a water-cooled base for laser cutting, and the water-cooled base can quickly absorb the heat generated during laser cutting, reducing the possibility of reducing the piezoelectric performance of the piezoelectric material block due to the heat generated during laser cutting.

[0081] For example, the laser cutting power can be 100 watts, 130 watts, 150 watts, 170 watts, 200 watts, etc. By using a laser cutting power of 100-200 watts, the laser cutting efficiency and the heat generated during laser cutting can be well balanced, so that the laser cutting efficiency is high while reducing the heat generated during laser cutting.

[0082] For example, the laser cutting speed can be 1 mm / min, 2 mm / min, 3 mm / min, 4 mm / min, 5 mm / min, etc. By using a laser cutting speed of 1-5 mm / min, the laser cutting speed can be large to make the preparation efficiency of the piezoelectric micro pillars 21 high, while the heat generated during laser cutting is small, thereby reducing the possibility of reducing the piezoelectric performance of the piezoelectric material block due to the heat generated during laser cutting.

[0083] Referring to Figures 1-2 According to some embodiments of the present application, silver electrodes 3 are plated on opposite sides of the piezoelectric body 2 along the first direction, comprising:

[0084] Double-sided polishing is performed on the opposite sides of the piezoelectric body 2 along the first direction, which can reduce the surface roughness of the piezoelectric body 2, so that the electrode material can be plated on the surface of the piezoelectric body 2 in the subsequent process;

[0085] The polished piezoelectric body 2 is placed in a vacuum chamber, and electrode material is plated on the opposite sides of the piezoelectric body 2 along the first direction by using a radio frequency magnetron sputtering method to plate silver electrodes 3 on the opposite sides of the piezoelectric body 2 along the first direction. By plating the electrode material on the surface of the polished piezoelectric body 2, the electrode material can be more uniformly attached to the surface of the piezoelectric body 2, reducing the gap between the electrode material and the piezoelectric body 2 and improving the bonding strength between the piezoelectric body 2 and the electrode material. Moreover, by using the radio frequency magnetron sputtering method to plate the electrode material on the opposite sides of the piezoelectric body 2 along the first direction, the electrode material can be more uniformly deposited on the surface of the piezoelectric body 2.

[0086] The surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm.

[0087] In the radio frequency magnetron sputtering method, the sputtering power is 500-1000 W.

[0088] The purity of silver in the electrode material is greater than 99.5%.

[0089] For example, the surface roughness Ra of the polished piezoelectric body 2 can be 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, etc. By making the surface roughness Ra of the polished piezoelectric body 2 less than 0.4 μm, the electrode material can be more uniformly attached to the surface of the piezoelectric body 2, reducing the gap between the electrode material and the piezoelectric body 2 and effectively improving the bonding strength between the piezoelectric body 2 and the electrode material.

[0090] For example, the sputtering power can be 500 W, 600 W, 700 W, 900 W, 100 W, etc. By making the sputtering power 500-1000 W, the efficiency of plating the silver electrodes 3 and the heat generated during the plating of the silver electrodes 3 can be better balanced. The sputtering power can be relatively large to make the efficiency of plating the silver electrodes 3 relatively high, and the electrode material can be more uniformly deposited on the surface of the piezoelectric body 2. Moreover, the heat generated during the plating of the silver electrodes 3 can be relatively small to reduce the impact of heat on the piezoelectric properties of the piezoelectric body 2.

[0091] For example, the purity of silver in the electrode material is 99.6%, 99.7%, 99.8%, 99.9%, etc. By making the purity of silver in the electrode material greater than 99.5%, the impurities in the electrode material are relatively small, and thus the silver electrodes 3 can have relatively strong conductivity.

[0092] Referring to Figures 1-2 According to some embodiments of the present application, the surfaces of the opposite sides of the piezoelectric body 2 along the first direction are polished on both sides, including:

[0093] The opposite sides of the piezoelectric body 2 along the first direction are polished on both sides by using silicon carbide sandpaper. The thickness of the single-sided piezoelectric body 2 removed in the first direction is less than 0.05 mm.

[0094] The mesh number of the silicon carbide sandpaper is 200-1200.

[0095] For example, the thickness of the single-sided piezoelectric body 2 removed in the first direction can be 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, or 0.05 mm. By removing the thickness of the single-sided piezoelectric body 2 in the first direction less than 0.05 mm, the surface roughness of the piezoelectric body 2 can be reduced to form a relatively flat surface, and the piezoelectric performance of the piezoelectric body 2 can be avoided due to the excessive removal of the single-sided piezoelectric body 2 in the first direction.

[0096] For example, if the thickness of the single-sided piezoelectric body 2 removed in the first direction is too large, at least part of the piezoelectric body 2 will be removed, which will reduce the piezoelectric area of the piezoelectric body 2 and reduce the piezoelectric performance of the piezoelectric body 2. By removing the thickness of the single-sided piezoelectric body 2 in the first direction less than 0.05 mm, the surface roughness of the piezoelectric body 2 can be reduced while avoiding excessive polishing to remove at least part of the piezoelectric body 2.

[0097] For example, the mesh number of the silicon carbide sandpaper can be 200, 400, 700, 1000, or 1200. By using the silicon carbide sandpaper with a mesh number of 200-1200, the surface roughness of the piezoelectric body 2 can be effectively reduced, and new scratches on the surface of the piezoelectric body 2 can be avoided due to the low mesh number of the sandpaper.

[0098] Referring to Figures 1-2 According to some embodiments of the present application, the ceramic protective layer 1 is arranged on the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction to obtain a narrow pulse stress sensor, which comprises:

[0099] The ceramic protective layer 1 is fixed on the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction by using an acrylate welding adhesive layer, and is cured at room temperature for 30-60 min to obtain a composite wafer narrow pulse stress sensor 100.

[0100] By using the acrylate welding adhesive layer to fix the ceramic protective layer 1 on the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction, the connection between the ceramic protective layer 1 and the silver electrode 3 is simple and has strong stability due to the strong adhesion of the acrylate welding adhesive layer, which effectively avoids the possibility of connection failure between the ceramic protective layer 1 and the silver electrode 3 due to external force impact.

[0101] For example, the curing time at room temperature can be 30 min, 40 min, 50 min, 60 min, etc. The acrylate welding adhesive layer can be solidified to make the ceramic protective layer 1 more stably fixed on the silver electrode 3.

[0102] The following will be described with reference toFigures 1-2 A preparation process of the composite wafer narrow pulse stress sensor 100 of the five embodiments is described.

[0103] Embodiment one, preparation of composite wafer narrow pulse stress sensor 100A1:

[0104] S1: The piezoelectric material block is placed on the water-cooled base for laser cutting, the laser cutting power is 100 watts, the cutting speed is 1 mm / min, the piezoelectric micro column 21 prepared has a thickness size t of 0.1 mm in the first direction, and the cross-sectional area of the piezoelectric micro column 21 is 1 mm 2 ;

[0105] S2: Stir the silicon carbide powder with a particle size of 100 nm with methylbenzene resin to prepare an organic silicon resin;

[0106] S3: Pour the prepared organic silicon resin into the prepared plurality of piezoelectric micro columns 21, the distance w between adjacent two piezoelectric micro columns 21 is 1 mm, and the piezoelectric body 2 is prepared after solidification;

[0107] S4: Adopt the 200 mesh silicon carbide sandpaper to polish the prepared piezoelectric body 2 along the opposite two sides in the first direction, the thickness removed by the single-sided piezoelectric body 2 in the first direction is less than 0.05 mm, and the surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm;

[0108] S5: Place the polished piezoelectric body 2 in the vacuum chamber, and use the radio frequency magnetron sputtering method to deposit the electrode material on the opposite two sides of the piezoelectric body 2 in the first direction, the sputtering power is 500 watts, and the deposition thickness h of the single-sided silver electrode 3 in the first direction is 10 μm;

[0109] S6: Select the ceramic protective layer 1 with a thickness size g of 0.1 mm in the first direction, and use the acrylate welding glue layer to bond and fix the ceramic protective layer 1 on the side of the silver electrode 3 in the first direction away from the piezoelectric body 2, and solidify at room temperature for 30 min to prepare the composite wafer narrow pulse stress sensor 100.

[0110] Embodiment two, preparation of composite wafer narrow pulse stress sensor 100A2:

[0111] S1: The piezoelectric material block is placed on the water-cooled base for laser cutting, the laser cutting power is 200 watts, the cutting speed is 5 mm / min, the piezoelectric micro column 21 prepared has a thickness size t of 2 mm in the first direction, and the cross-sectional area of the piezoelectric micro column 21 is 25 mm 2 ;

[0112] S2: Stir the silicon carbide powder with a particle size of 800 nm with methylbenzene resin to prepare an organic silicon resin;

[0113] S3: The prepared organic silicone resin is poured into the prepared plurality of piezoelectric micro pillars 21, the interval w between two adjacent piezoelectric micro pillars 21 is 2 mm, and the piezoelectric body 2 is prepared after curing;

[0114] S4: The prepared piezoelectric body 2 is polished on both sides along the first direction using a silicon carbide sandpaper with a mesh number of 1200, the thickness removed by the single-sided piezoelectric body 2 in the first direction is less than 0.05 mm, and the surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm;

[0115] S5: The polished piezoelectric body 2 is placed in a vacuum chamber, and an electrode material is plated on the opposite sides of the piezoelectric body 2 along the first direction by a radio frequency magnetron sputtering method, the sputtering power is 1000 watts, and the deposition thickness h of the single-sided silver electrode 3 in the first direction is 50 μm;

[0116] S6: A ceramic protective layer 1 with a thickness size g of 0.5 mm in the first direction is selected, the ceramic protective layer 1 is adhered and fixed to the side of the silver electrode 3 away from the piezoelectric body 2 along the first direction by an acrylate welding glue layer, and the composite wafer narrow pulse stress sensor 100 is prepared after curing at room temperature for 60 min.

[0117] Example Three, Preparation of Composite Wafer Narrow Pulse Stress Sensor 100A3:

[0118] S1: The piezoelectric material block is placed on a water-cooled base for laser cutting, the laser cutting power is 150 watts, the cutting speed is 4 mm / min, the thickness size t of the prepared piezoelectric micro pillar 21 in the first direction is 1 mm, and the cross-sectional area of the piezoelectric micro pillar 21 is 15 mm 2 ;

[0119] S2: The silicon carbide powder with a particle size of 400 nm is stirred with methylbenzene resin to prepare an organic silicone resin;

[0120] S3: The prepared organic silicone resin is poured into the prepared plurality of piezoelectric micro pillars 21, the interval w between two adjacent piezoelectric micro pillars 21 is 1 mm, and the piezoelectric body 2 is prepared after curing;

[0121] S4: The prepared piezoelectric body 2 is polished on both sides along the first direction using a silicon carbide sandpaper with a mesh number of 800, the thickness removed by the single-sided piezoelectric body 2 in the first direction is less than 0.05 mm, and the surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm;

[0122] S5: The polished piezoelectric body 2 is placed in a vacuum chamber, and an electrode material is plated on the opposite sides of the piezoelectric body 2 along the first direction by a radio frequency magnetron sputtering method, the sputtering power is 800 watts, and the deposition thickness h of the single-sided silver electrode 3 in the first direction is 20 μm;

[0123] S6: A ceramic protective layer 1 with a thickness dimension g of 0.3 mm in the first direction is selected, and the ceramic protective layer 1 is bonded and fixed to the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction by using an acrylate welding adhesive layer, and is cured at room temperature for 40 min to obtain a composite wafer narrow pulse stress sensor 100.

[0124] Example Four, Preparation of a Composite Wafer Narrow Pulse Stress Sensor 100A4:

[0125] S1: The piezoelectric material block is placed on a water-cooled base for laser cutting, the laser cutting power is 180 W, and the cutting speed is 4 mm / min. The piezoelectric microcolumn 21 obtained has a thickness dimension t of 1.5 mm in the first direction, and the cross-sectional area of the piezoelectric microcolumn 21 is 20 mm 2 ;

[0126] S2: The silicon carbide powder with a particle size of 600 nm is stirred with methylbenzene resin to obtain an organic silicon resin;

[0127] S3: The obtained organic silicon resin is poured into the obtained plurality of piezoelectric microcolumns 21, and the distance w between adjacent two piezoelectric microcolumns 21 is 1.5 mm. After curing, the piezoelectric body 2 is obtained;

[0128] S4: The obtained piezoelectric body 2 is polished on both sides in the first direction by using a silicon carbide sandpaper with a mesh number of 600. The thickness removed by the single-sided piezoelectric body 2 in the first direction is less than 0.05 mm, and the surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm;

[0129] S5: The polished piezoelectric body 2 is placed in a vacuum chamber, and an electrode material is plated on the opposite sides of the piezoelectric body 2 in the first direction by using a radio frequency magnetron sputtering method. The sputtering power is 700 W, so that the deposition thickness h of the single-sided silver electrode 3 in the first direction is 25 μm;

[0130] S6: A ceramic protective layer 1 with a thickness dimension g of 0.4 mm in the first direction is selected, and the ceramic protective layer 1 is bonded and fixed to the side of the silver electrode 3 away from the piezoelectric body 2 in the first direction by using an acrylate welding adhesive layer, and is cured at room temperature for 40 min to obtain a composite wafer narrow pulse stress sensor 100.

[0131] Example Five, Preparation of a Composite Wafer Narrow Pulse Stress Sensor 100A5:

[0132] S1: The piezoelectric material block is placed on a water-cooled base for laser cutting, the laser cutting power is 180 W, and the cutting speed is 3 mm / min. The piezoelectric microcolumn 21 obtained has a thickness dimension t of 0.8 mm in the first direction, and the cross-sectional area of the piezoelectric microcolumn 21 is 15 mm 2 ;

[0133] S2: Stir the silicon carbide powder with a particle size of 600 nm with methylbenzene resin to obtain an organic silicon resin;

[0134] S3: Pour the obtained organic silicon resin into the obtained plurality of piezoelectric micro pillars 21, the distance w between two adjacent piezoelectric micro pillars 21 is 1.5 mm, and the piezoelectric body 2 is obtained after solidification;

[0135] S4: Double-side polish the obtained piezoelectric body 2 along the opposite sides in the first direction using a silicon carbide sandpaper with a mesh number of 400, the thickness of a single-side piezoelectric body 2 removed in the first direction is less than 0.05 mm, and the surface roughness Ra of the polished piezoelectric body 2 is less than 0.4 μm;

[0136] S5: Place the polished piezoelectric body 2 in a vacuum chamber, and use a radio frequency magnetron sputtering method to deposit an electrode material on the opposite sides of the piezoelectric body 2 in the first direction, the sputtering power is 900 watts, so that the deposition thickness h of a single-side silver electrode 3 in the first direction is 40 μm;

[0137] S6: Select a ceramic protective layer 1 with a thickness size g of 0.4 mm in the first direction, and use an acrylate welding glue layer to bond and fix the ceramic protective layer 1 on the side of the silver electrode 3 in the first direction away from the piezoelectric body 2, and solidify at room temperature for 50 min to obtain a composite wafer narrow pulse stress sensor 100.

[0138] Referring to Figures 1-2 and Figures 1-2 , Figures 1-2 is a waveform diagram of an ultrasonic wave excited by the composite wafer narrow pulse stress sensor 100 obtained according to some embodiments of the present application, Figures 1-2 is a waveform diagram of an ultrasonic wave excited by a stress sensor in the related art, in which the abscissa represents the acoustic time, in microseconds (Ms), and the ordinate represents the voltage, in volts (V).

[0139] From Figure 3 it can be seen that the ultrasonic wave excited by the stress sensor in the related art is a wide pulse signal, the tail wave of the ultrasonic wave signal is long, and the signal extraction is difficult, Figure 4 it can be seen that the ultrasonic wave signal excited by the composite wafer narrow pulse stress sensor 100 is a narrow pulse signal, the tail wave is short, the waveform is simple, and the signal extraction is easy, Figure 3 and Figure 4 Figure 4 Figure 3 Figure 3 Figure 4It can be seen from the comparison that the ultrasonic signal waveform excited by the composite wafer narrow pulse stress sensor 100 is relatively simple, and the signal extraction difficulty is relatively low, so that the difficulty of the subsequent processing module for processing the ultrasonic signal excited by the composite wafer narrow pulse stress sensor 100 can be effectively reduced, and the accuracy of the stress measured according to the ultrasonic signal excited by the composite wafer narrow pulse stress sensor 100 can be improved.

[0140] For example, when the composite wafer narrow pulse stress sensor 100 is applied to the wind power bolt 200, the ultrasonic signal excited by the composite wafer narrow pulse stress sensor 100 is a narrow pulse signal, the positions of the wave peak and the wave trough of the ultrasonic signal can be accurately measured, and the waveform is relatively simple, so that the accuracy of the stress of the wind power bolt 200 measured according to the ultrasonic signal excited by the composite wafer narrow pulse stress sensor 100 can be improved.

[0141] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0142] In the description of the present application, "first feature" and "second feature" can include one or more features.

[0143] In the description of the present application, the "first feature" above or below the "second feature" can include that the first and second features are in direct contact, or can include that the first and second features are not in direct contact but are in contact through another feature between them.

[0144] In the description of the present application, the "first feature" above, above and above the "second feature" includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher than the second feature in horizontal height.

[0145] In the description of the specification, reference to "one embodiment", "some embodiments", "an exemplary embodiment", "an example", "a specific example", or "some examples" means that a particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the application. The appearances of the phrases "in one embodiment", "in some embodiments", "in an exemplary embodiment", "an example", "a specific example", or "some examples" in various places in the specification are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0146] Although embodiments of the application have been shown and described, it will be appreciated that those skilled in the art can make various changes, modifications, substitutions and alterations thereto without departing from the principles and scope of the application, which are defined by the claims and their equivalents.

Claims

1. A composite wafer narrow pulse stress sensor, characterized in that, include: A piezoelectric body, comprising piezoelectric micropillars and an organosilicon resin matrix, wherein there are multiple piezoelectric micropillars, which are spaced apart within the organosilicon resin matrix, and the organosilicon resin matrix comprises silicon carbide powder and methylphenyl silicone resin. Silver electrodes are disposed on opposite sides of the piezoelectric body in the first direction; A ceramic protective layer is located on the side of the silver electrode opposite to the piezoelectric element along the first direction.

2. The composite wafer narrow pulse stress sensor according to claim 1, characterized in that, The thickness of the piezoelectric micropillar in the first direction is 0.1 mm to 2 mm; and / or, the cross-sectional area of ​​the piezoelectric micropillar is 1 mm². 2 ~25mm 2 The cross-section of the piezoelectric micropillar is perpendicular to the first direction.

3. The composite wafer narrow pulse stress sensor according to claim 1, characterized in that, The piezoelectric micropillars are arranged at intervals in the same plane perpendicular to the first direction; and / or the spacing between two adjacent piezoelectric micropillars is 0.1 mm to 2 mm.

4. The composite wafer narrow pulse stress sensor according to claim 1, characterized in that, The deposition thickness of the silver electrode on one side in the first direction is 10 μm to 50 μm.

5. The composite wafer narrow pulse stress sensor according to claim 1, characterized in that, The silicon carbide powder has a particle size of 100 nm to 800 nm; and / or the ceramic protective layer has a thickness of 0.1 mm to 0.5 mm in the first direction.

6. A method for fabricating a composite wafer narrow pulse stress sensor, characterized in that, The composite wafer narrow pulse stress sensor is a composite wafer narrow pulse stress sensor according to any one of claims 1-5, comprising the following steps: Prepare the piezoelectric material; The silver electrodes are plated on opposite sides of the piezoelectric body along the first direction; The ceramic protective layer is disposed on the side of the silver electrode opposite to the piezoelectric body along the first direction to obtain the composite wafer narrow pulse stress sensor; Among them, laser cutting method is used to cut piezoelectric material blocks to obtain multiple piezoelectric micropillars; The piezoelectric preform is prepared by bonding and fixing multiple piezoelectric micropillars with silicone resin.

7. The method for fabricating the composite wafer narrow pulse stress sensor according to claim 6, The piezoelectric material block is cut using a laser cutting method to obtain multiple piezoelectric micropillars, including: The piezoelectric material block was placed on a water-cooled substrate and laser-cut with a laser cutting power of 100 watts to 200 watts and a laser cutting speed of 1 mm / min to 5 mm / min to obtain multiple piezoelectric micropillars. The piezoelectric body is prepared by bonding and fixing multiple piezoelectric micropillars with silicone resin, comprising: The organosilicon resin was prepared by stirring silicon carbide powder with methylphenyl silicone resin. The piezoelectric body is obtained by casting the silicone resin into a plurality of piezoelectric micropillars and curing it.

8. The method for fabricating a composite wafer narrow pulse stress sensor according to claim 6, characterized in that, The silver electrodes are deposited on opposite sides of the piezoelectric body along the first direction, comprising: The piezoelectric material is polished on both sides along the first direction; The polished piezoelectric body is placed in a vacuum chamber, and electrode material is deposited on opposite sides of the piezoelectric body along the first direction using a radio frequency magnetron sputtering method, so as to deposit the silver electrode on opposite sides of the piezoelectric body along the first direction. The surface roughness Ra of the polished piezoelectric material is less than 0.4 μm; In the radio frequency magnetron sputtering method, the sputtering power is 500 watts to 1000 watts; The purity of silver in the electrode material is greater than 99.5%.

9. The method for fabricating a composite wafer narrow pulse stress sensor according to claim 8, characterized in that, Polishing the surfaces of the piezoelectric element on both sides along the first direction includes: The piezoelectric material is polished on both sides along the first direction using silicon carbide sandpaper, and the thickness removed from one side of the piezoelectric material in the first direction is less than 0.05 mm. The silicon carbide sandpaper has a mesh size of 200 to 1200.

10. The method for fabricating a composite wafer narrow pulse stress sensor according to claim 6, characterized in that, A narrow pulse stress sensor is fabricated by disposing the ceramic protective layer on the side of the silver electrode opposite to the piezoelectric body along the first direction, comprising: The ceramic protective layer is bonded and fixed to the silver electrode on the side opposite to the piezoelectric body along the first direction using an acrylic welding adhesive layer, and cured at room temperature for 30 min to 60 min to obtain the composite wafer narrow pulse stress sensor.

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