High-hardness high-entropy AlCrNbSiTi composite electrode for bolt stress sensor and preparation method of high-hardness high-entropy AlCrNbSiTi composite electrode

Abstract

The invention discloses a high-hardness and high-entropy AlCrNbSiTi composite electrode for a bolt stress sensor and a preparation method of the high-hardness and high-entropy AlCrNbSiTi composite electrode, the high-hardness and high-entropy AlCrNbSiTi composite electrode has a gradient layer structure, the high-hardness and high-entropy AlCrNbSiTi composite electrode comprises an adhesion barrier layer and a conductive layer, the adhesion barrier layer and the conductive layer are used for being combined with a piezoelectric material, the adhesion barrier layer is a Cr combination layer, and the conductive layer is an AlCrNbSiTi conductive layer. According to the high-hardness and high-entropy AlCrNbSiTi composite electrode for the bolt stress sensor disclosed by the embodiment of the invention, the high-hardness and high-entropy AlCrNbSiTi composite electrode is good in wear resistance, long in service life, low in manufacturing cost, not easy to break and not easy to fall off from a piezoelectric material.

Description

Technical Field

[0001] This invention relates to the field of thin film materials technology, and in particular to a high-hardness, high-entropy AlCrNbSiTi composite electrode for bolt stress sensors and its preparation method. Background Technology

[0002] A bolt stress sensor is a device that directly measures preload using an integrated bolt sensor. Its principle is to integrate a piezoelectric element into the bolt, transforming the bolt into a force sensor that can continuously determine whether the bolt being tightened has reached the designed preload. Piezoelectric sensors have broad application prospects in bolt preload measurement. They generate ultrasonic waves through a pressure sensor, and the change in preload is obtained by measuring the change in the propagation time of the ultrasonic waves within the bolt. In the structure of a bolt stress sensor, the electrodes are a crucial component. Their function is to provide an effective electrical interface for the piezoelectric element, used to collect the generated charge or apply an excitation electric field. The performance of the electrode material directly determines the sensor's sensitivity, reliability, stability, frequency response, and lifespan.

[0003] In related technologies, the commonly used electrode materials in piezoelectric stress sensors mainly include the following categories: precious metals such as gold, silver, and platinum, and their alloys; high-melting-point metals such as molybdenum and tungsten; and metal oxides such as indium tin oxide. Precious metals such as gold, silver, and platinum possess excellent conductivity and chemical stability. However, these precious metals are soft, have extremely low hardness, and poor wear resistance, making them prone to scratches, wear, and even detachment during sensor manufacturing or use, leading to electrode failure. Furthermore, the high cost of precious metals restricts cost control in large-scale applications. High-melting-point metals such as molybdenum and tungsten have high hardness, melting point, and high-temperature stability, which can improve the wear resistance and diffusion resistance of electrodes to some extent. However, their electrical conductivity is significantly lower than that of precious metals, introducing greater resistance losses. Simultaneously, these metals have poor ductility and are prone to brittle fracture under cyclic stress. Indium tin oxide is brittle and prone to brittle fracture, making it unsuitable for flexible applications or applications requiring deformation, and its electrical conductivity still lags behind that of metals.

[0004] It is evident that the metal electrodes in bolt pressure sensors in related technologies suffer from problems such as poor wear resistance, short lifespan, high manufacturing cost, susceptibility to breakage, and easy detachment. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a high-hardness, high-entropy AlCrNbSiTi composite electrode for bolt stress sensors, which has good wear resistance, long life, low manufacturing cost, is not prone to fracture, and is not prone to detachment from the piezoelectric material.

[0006] According to a first aspect embodiment of the present invention, a high-hardness, high-entropy AlCrNbSiTi composite electrode for a bolt stress sensor is provided, wherein the high-hardness, high-entropy AlCrNbSiTi composite electrode has a gradient layer structure, and the AlCrNbSiTi composite electrode includes an adhesion barrier layer and a conductive layer for bonding with a piezoelectric material, wherein the adhesion barrier layer is a Cr bonding layer, and the conductive layer is an AlCrNbSiTi conductive layer.

[0007] The high-hardness, high-entropy AlCrNbSiTi composite electrode for bolt stress sensors according to embodiments of the present invention utilizes the excellent conductivity and mechanical properties of AlCrNbSiTi to enhance wear resistance while maintaining high conductivity, making the AlCrNbSiTi composite electrode less prone to wear failure. By utilizing the hysteresis diffusion effect of the high-entropy alloy, the migration and diffusion of metal atoms in the AlCrNbSiTi coating at high temperatures can be suppressed, thereby preventing the diffusion of metal atoms from the AlCrNbSiTi conductive layer into the piezoelectric material and extending the lifespan of the AlCrNbSiTi composite electrode. Al, Cr, Nb, Si, and Ti are all common and readily available metallic elements, which can reduce the production costs of the AlCrNbSiTi composite electrode. Cost reduction; furthermore, by using an adhesion barrier layer with a Cr bonding layer, the Cr on the surface of the Cr bonding layer in contact with the piezoelectric material can form a strong chemical bond with the piezoelectric material, and the Cr on the surface of the Cr bonding layer in contact with the AlCrNbSiTi conductive layer can also form a strong chemical bond with the AlCrNbSiTi conductive layer. This can prevent the AlCrNbSiTi conductive layer from detaching from the piezoelectric substrate. At the same time, the Cr bonding layer can further prevent metal atoms in the AlCrNbSiTi conductive layer from diffusing into the piezoelectric material. The Cr bonding layer can also passivate cracks and absorb vibration energy, so that the AlCrNbSiTi composite electrode maintains good toughness, avoids brittle cracking of the AlCrNbSiTi composite electrode, and improves the service life and stability of the piezoelectric stress sensor.

[0008] According to some embodiments of the present invention, the thickness of the adhesion barrier layer is 10~1000 nm.

[0009] According to some embodiments of the present invention, the thickness of the conductive layer is 1~20μm.

[0010] A method for preparing a high-hardness, high-entropy AlCrNbSiTi composite electrode according to a second aspect of the present invention, wherein the preparation method prepares the high-hardness, high-entropy AlCrNbSiTi composite electrode according to a first aspect of the present invention, the preparation method employing an arc ion plating process and comprising the following steps: Step (1): In an argon atmosphere, the adhesion barrier layer is deposited on the surface of the piezoelectric material substrate to form the adhesion barrier layer; Step (2): In an argon atmosphere, the conductive layer is deposited on the surface of the adhesion barrier layer to complete the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode.

[0011] The method for preparing a high-hardness, high-entropy AlCrNbSiTi composite electrode according to an embodiment of the present invention employs an arc ion plating process to ionize Cr and AlCrNbSiTi particles. These ionized particles possess high energy, and during deposition, they bombard the surface of the piezoelectric material substrate, producing an effect similar to "atomic spray welding." This results in excellent adhesion of the adhesion barrier layer and conductive layer deposited by the arc ion plating process, making it difficult for the Cr bonding layer and AlCrNbSiTi conductive layer to detach. Furthermore, the arc ion plating process allows for rapid deposition of Cr and AlCrNbSiTi, improving coating production efficiency. The deposition time of the arc ion plating process is adjustable, facilitating control of the thickness of the adhesion barrier layer and conductive layer. By first depositing an adhesion barrier layer on the surface of the piezoelectric material substrate in an argon atmosphere, the adhesion barrier layer adheres to the piezoelectric material substrate through chemical bonding. Then, a conductive layer is deposited on the surface of the adhesion barrier layer, preventing direct contact between the conductive layer and the piezoelectric material substrate, thereby enhancing the adhesion effect of the conductive layer and preventing it from detaching.

[0012] According to some embodiments of the present invention, the ambient temperature is maintained at 50~500℃ during the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode.

[0013] According to some embodiments of the present invention, in step (1), the deposition uses a Cr target, the arc power supply pulse duty cycle of the Cr target is 10%~80%, and the deposition bias voltage is -50~-150V.

[0014] According to some embodiments of the present invention, in step (1), the ambient gas pressure for deposition is 0.1~2 Pa.

[0015] According to some embodiments of the present invention, in step (2), the deposition uses an AlCrNbSiTi target, the arc power supply pulse duty cycle of the AlCrNbSiTi target is 10%-80%, and the deposition bias voltage is 0~-250V.

[0016] According to some embodiments of the present invention, in step (2), the ambient air pressure during deposition is 1~5 Pa.

[0017] According to some embodiments of the present invention, in step (2), the deposition time is 1 to 60 min.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a cross-sectional view of a high-hardness, high-entropy AlCrNbSiTi composite electrode and a piezoelectric material matrix according to some embodiments of the present invention; Figure 2 This is a schematic flowchart of a method for preparing a high-hardness, high-entropy AlCrNbSiTi composite electrode according to some embodiments of the present invention. Figure 3 This is a schematic diagram of a coating preparation apparatus used in the preparation process of a high-hardness, high-entropy AlCrNbSiTi composite electrode according to some embodiments of the present invention. Figure 4 This is a surface morphology diagram of the high-hardness, high-entropy AlCrNbSiTi composite electrode according to Embodiment 2 of the present invention; Figure 5 This is a cross-sectional morphology diagram of the high-hardness, high-entropy AlCrNbSiTi composite electrode according to Embodiment 2 of the present invention; Figure 6 This is a high-resolution transmission electron microscope image of the cross-section of the high-hardness, high-entropy AlCrNbSiTi composite electrode according to Embodiment 2 of the present invention. Figure 7 The wear resistance test results are those of the high-hardness, high-entropy AlCrNbSiTi composite electrode according to Embodiment 2 of the present invention. Figure 8 This is a graph showing the changes in elemental composition of the high-hardness, high-entropy AlCrNbSiTi composite electrode after annealing at different temperatures according to Embodiment 2 of the present invention.

[0020] Figure label: 100. High-hardness, high-entropy AlCrNbSiTi composite electrode; 10. Cr bonding layer; 20. AlCrNbSiTiN conductive layer; 30. Piezoelectric material matrix; 200. Coating preparation apparatus; 40. AlCrNbSiTi target; 50. Cr target; 60. Sample holder; 61. Sample; 70. Heating rod; 80. Vacuum port. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0022] The following is for reference. Figures 1-2 A high-hardness, high-entropy AlCrNbSiTi composite electrode 100 for a bolt stress sensor is described according to an embodiment of the present invention.

[0023] refer to Figure 1 According to a first aspect embodiment of the present invention, a high-hardness, high-entropy AlCrNbSiTi composite electrode 100 for a bolt stress sensor has a gradient layer structure and includes an adhesion barrier layer and a conductive layer for bonding with a piezoelectric material. The adhesion barrier layer is a Cr bonding layer 10, and the conductive layer is an AlCrNbSiTi conductive layer.

[0024] Among them, high-entropy materials exhibit lattice distortion effects. The AlCrNbSiTi conductive layer contains atoms of Al, Cr, Nb, Si, and Ti elements. Due to the large differences in the atomic sizes of Al, Cr, Nb, Si, and Ti, the uncertainty of atomic occupancy increases, causing lattice distortion within the AlCrNbSiTi conductive layer. This distortion hinders dislocation movement, thereby increasing the hardness and strength of the AlCrNbSiTi conductive layer. Furthermore, the AlCrNbSiTi conductive layer contains crystalline phases that separate the AlCrNbSiTi amorphous phase, forming a nanocrystalline / amorphous nanocomposite structure. This structure can improve the wear resistance and scratch resistance of the AlCrNbSiTi conductive layer, enhancing wear resistance while maintaining its high conductivity, making the AlCrNbSiTi composite electrode less prone to wear failure.

[0025] High-entropy materials also exhibit a hysteresis diffusion effect. The strong interactions between atoms of Al, Cr, Nb, Si, and Ti elements and the lattice distortion effect in the AlCrNbSiTi conductive layer can hinder atomic diffusion, resulting in a significantly lower diffusion rate of metal atoms in the AlCrNbSiTi conductive layer compared to that in ordinary alloys. This improves the stability of the AlCrNbSiTi composite electrode and extends its lifespan.

[0026] The adhesion barrier layer serves to adhere the AlCrNbSiTi conductive layer and the piezoelectric material, and to prevent the diffusion of metal atoms. By making the adhesion barrier layer a Cr bonding layer 10, both sides of the Cr bonding layer 10 are in contact with the AlCrNbSiTi conductive layer and the piezoelectric material, respectively. The Cr on the surface of the Cr bonding layer 10 in contact with the piezoelectric material forms a strong chemical bond with the piezoelectric material, and the Cr on the surface of the Cr bonding layer 10 in contact with the AlCrNbSiTi conductive layer also forms a strong chemical bond with the AlCrNbSiTi conductive layer. This effectively adheres the AlCrNbSiTi conductive layer and the piezoelectric material, preventing the AlCrNbSiTi conductive layer from detaching from the piezoelectric substrate. Furthermore, the Cr bonding layer 10 can further prevent the migration and diffusion of metal atoms from the AlCrNbSiTi conductive layer into the piezoelectric material at high temperatures, thereby extending the lifespan of the AlCrNbSiTi composite electrode.

[0027] The formation of multiple interfaces and numerous grain and phase boundaries between the Cr bonding layer 10 and the AlCrNbSiTi conductive layer facilitates the passivation of cracks and absorption of vibration energy by the Cr bonding layer 10, enabling the AlCrNbSiTi composite electrode to maintain good toughness and preventing brittle cracking. This, in turn, improves the service life and stability of the bolt stress sensor.

[0028] The high-hardness, high-entropy AlCrNbSiTi composite electrode 100 for bolt stress sensors according to embodiments of the present invention utilizes the excellent conductivity and mechanical properties of AlCrNbSiTi to enhance wear resistance while maintaining high conductivity, making the AlCrNbSiTi composite electrode less prone to wear failure. By utilizing the hysteresis diffusion effect of the high-entropy alloy, the migration and diffusion of metal atoms in the AlCrNbSiTi coating at high temperatures can be suppressed, thereby preventing the diffusion of metal atoms from the AlCrNbSiTi conductive layer into the piezoelectric material and extending the lifespan of the AlCrNbSiTi composite electrode. Al, Cr, Nb, Si, and Ti are all common and readily available metallic elements, which can reduce the production cost of the AlCrNbSiTi composite electrode; and Furthermore, by providing an adhesion barrier layer with Cr bonding layer 10, the Cr on the surface of Cr bonding layer 10 in contact with the piezoelectric material can form a strong chemical bond with the piezoelectric material, and the Cr on the surface of Cr bonding layer 10 in contact with the AlCrNbSiTi conductive layer can also form a strong chemical bond with the AlCrNbSiTi conductive layer. This can prevent the AlCrNbSiTi conductive layer from detaching from the piezoelectric material. At the same time, Cr bonding layer 10 can further prevent metal atoms in the AlCrNbSiTi conductive layer from diffusing into the piezoelectric material. Cr bonding layer 10 can also passivate cracks and absorb vibration energy, so that the AlCrNbSiTi composite electrode maintains good toughness, avoids brittle cracking of the AlCrNbSiTi composite electrode, and improves the service life and stability of the bolt stress sensor.

[0029] According to some embodiments of the present invention, the thickness of the adhesion barrier layer is 10~1000 nm.

[0030] For example, the thickness of the adhesion barrier layer can be 10 nm, 50 nm, 100 nm, 500 nm, 1000 nm, etc. If the adhesion barrier layer is too thick, the AlCrNbSiTi composite electrode will be too thick overall, occupying too much space; if the adhesion barrier layer is too thin, the number of Cr atoms will be too small to form chemical bonds, resulting in a reduction in the adhesion effect.

[0031] By making the thickness of the adhesion barrier layer 10~1000nm, the adhesion barrier layer can play a good adhesion role while reducing the space occupied by the adhesion barrier layer.

[0032] According to some embodiments of the present invention, the thickness of the conductive layer is 1~20μm.

[0033] For example, the thickness of the conductive layer can be 1μm, 5μm, 10μm, 15μm, 20μm, etc. If the thickness of the conductive layer is too thick, it will increase the burden on the adhesion barrier layer, causing the conductive layer to easily fall off; if the thickness of the conductive layer is too thin, it will reduce the life of the conductive layer, and the conductive layer will be more likely to fail under long-term working wear.

[0034] By making the thickness of the conductive layer 1~20μm, the conductive layer is less likely to fall off while increasing its lifespan.

[0035] refer to Figure 2 According to a second aspect embodiment of the present invention, a method for preparing a high-hardness, high-entropy AlCrNbSiTi composite electrode 100 is provided. The method prepares the high-hardness, high-entropy AlCrNbSiTi composite electrode 100 according to a first aspect embodiment of the present invention. The preparation method employs an arc ion plating process and includes the following steps: Step (1): In an argon atmosphere, an adhesion barrier layer is deposited on the surface of the piezoelectric material substrate 30 to form a chemical bond between the surface of the piezoelectric material and the adhesion barrier layer. Step (2): In an argon atmosphere, a conductive layer is deposited on the surface of the adhesion barrier layer to form a chemical bond between the conductive layer and the adhesion barrier layer, thus completing the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0036] Among them, the arc ion plating process is a physical vapor deposition process. This technology triggers the arc discharge between the cathode target and the anode in an argon atmosphere, causing the AlCrNbSiTi target 40 and Cr target 50 to evaporate and ionize to form a metal vapor plasma, which is then deposited onto the surface of the piezoelectric material substrate 30.

[0037] According to the preparation method of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100 of the present invention, an arc ion plating process is used to ionize Cr and AlCrNbSiTi particles. The ionized particles have high energy. These high-energy particles bombard the surface of the piezoelectric material substrate 30 during the deposition process, producing an effect similar to "atomic spray welding". This results in good adhesion of the adhesion barrier layer and conductive layer deposited by the arc ion plating process, making it difficult for the Cr bonding layer 10 and the AlCrNbSiTi conductive layer to fall off. In addition, the arc ion plating process allows for a fast deposition rate of Cr and AlCrNbSiTi, improving the production efficiency of the coating. The deposition time of the arc ion plating process can be adjusted, making it easy to control the thickness of the adhesion barrier layer and the conductive layer. By first depositing the adhesion barrier layer on the surface of the piezoelectric material substrate 30 in an argon atmosphere, the adhesion barrier layer and the piezoelectric material substrate 30 are chemically bonded together. Then, a conductive layer is deposited on the surface of the adhesion barrier layer to avoid direct contact between the conductive layer and the piezoelectric material substrate 30, thereby improving the adhesion effect of the conductive layer and preventing it from falling off.

[0038] According to some embodiments of the present invention, the ambient temperature is maintained at 50~500℃ during the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0039] For example, during the fabrication of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100, the ambient temperature can be maintained at 50℃, 100℃, 200℃, 300℃, 400℃, 500℃, etc. If the ambient temperature is too high, the coating will be difficult to solidify during the arc ion plating process, making it difficult to deposit on the surface of the piezoelectric material substrate 30; if the ambient temperature is too low, the migration rate of ionized particles will be reduced, resulting in a decrease in the uniformity of the adhesion barrier layer and the conductive layer.

[0040] By maintaining the ambient temperature at 50~500℃ during the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100, it is possible to ionize Cr and AlCrNbSiTi particles while simultaneously promoting the solidification of Cr and AlCrNbSiTi into solid form, allowing them to be uniformly deposited on the surface of the piezoelectric material matrix 30.

[0041] According to some embodiments of the present invention, in step (1), Cr target 50 is used for deposition, the duty cycle of the arc power supply pulse of Cr target 50 is 10%~80%, and the deposition bias voltage is -50~-150V.

[0042] For example, the duty cycle of the arc power supply pulse for Cr target 50 can be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc.; the deposition bias voltage can be -50V, -100V, -150V, etc.

[0043] By setting the duty cycle of the arc power pulse of the Cr target 50 to 10%~80% and the deposition bias voltage to -50~-150V in step (1), the Cr particles emitted by the Cr target 50 can be made more uniform, resulting in better uniformity of the Cr bonding layer 10 deposited on the surface of the piezoelectric material substrate 30.

[0044] According to some embodiments of the present invention, in step (1), the ambient gas pressure for deposition is 0.1~2 Pa.

[0045] For example, the ambient gas pressure during deposition in step (1) is 0.1 Pa, 0.5 Pa, 1 Pa, 1.5 Pa, 2 Pa, etc. If the ambient gas pressure during the deposition of the adhesion barrier layer is too low, the deposition rate will be too fast, which will easily cause uneven thickness of the adhesion barrier layer; if the ambient gas pressure during the deposition of the adhesion barrier layer is too high, the deposition rate will be too slow and the process time will be too long.

[0046] By setting the ambient pressure for deposition in step (1) to 1~5 Pa, the thickness of the adhesion barrier layer can be made more uniform while shortening the process time.

[0047] According to some embodiments of the present invention, in step (2), the deposition uses an AlCrNbSiTi target 40, the duty cycle of the arc power supply pulse of the AlCrNbSiTi target 40 is 10%-80%, and the deposition bias voltage is 0~-250V.

[0048] For example, the duty cycle of the arc power supply pulse for AlCrNbSiTi target 40 can be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc.; the deposition bias voltage can be 0V, -50V, -100V, -150V, -200V, -250V, etc.

[0049] By setting the duty cycle of the arc power supply pulse of the AlCrNbSiTi target 40 to 10%~80% and the deposition bias voltage to -50~-150V in step (2), the AlCrNbSiTi particles emitted by the AlCrNbSiTi target 40 can be made more uniform, resulting in better uniformity of the AlCrNbSiTi bonding layer deposited on the surface of the Cr bonding layer 10.

[0050] According to some embodiments of the present invention, in step (2), the ambient air pressure during deposition is 1~5 Pa.

[0051] For example, the ambient pressure for conductive layer deposition can be 1 Pa, 2 Pa, 3 Pa, 4 Pa, 5 Pa, etc. If the ambient pressure during conductive layer deposition is too low, the deposition rate will be too fast, which can easily lead to uneven thickness of the conductive layer; if the ambient pressure during conductive layer deposition is too high, the deposition rate will be too slow, and the process time will be too long.

[0052] By setting the ambient pressure during deposition in step (2) to 1~5 Pa, the thickness of the conductive layer can be made more uniform while shortening the process time.

[0053] According to some embodiments of the present invention, in step (2), the deposition time is 1 to 60 min.

[0054] For example, the deposition time of the conductive layer can be 1 min, 5 min, 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, etc. If the deposition time of the conductive layer is too short, the thickness of the conductive layer will be too thin, which will easily reduce the life of the conductive layer. Under long-term working wear, the conductive layer is more likely to fail. If the deposition time of the conductive layer is too long, the thickness of the conductive layer will be too thick, which will increase the burden on the adhesion barrier layer on the conductive layer, and the conductive layer will be easy to fall off.

[0055] By setting the deposition time in step (2) to 1~60 min, the thickness of the conductive layer is moderate, which is beneficial for the conductive layer to adhere to the adhesion barrier layer and also extends the life of the conductive layer.

[0056] The high-hardness, high-entropy AlCrNbSiTi composite electrode 100 for bolt stress sensors of the present invention and its preparation method are further described below with reference to embodiments.

[0057] Example 1, refer to Figures 1-3 In this embodiment, the following is adopted: Figure 3 The coating preparation apparatus 200 shown is used for preparation. The vacuum chamber of the apparatus is surrounded by the furnace wall, and the dimensions of the vacuum chamber are 800×800×800 mm. The vacuum chamber is equipped with a vacuum port 80, and the vacuum pump unit evacuates the vacuum chamber through the vacuum port 80. There are heating rods 70 at the four corners of the vacuum chamber, with a heating power of 10~30kW. Two Cr targets 50 and two AlCrNbSiTi targets 40 are installed respectively, and the Cr targets 50 and AlCrNbSiTi targets 40 are arranged at intervals along the furnace wall. Then, the sample 61 is placed on the sample holder 60.

[0058] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 150 °C. Then, argon gas is introduced and the ambient pressure is controlled at 0.5 Pa. The bias voltage and arc power supply are turned on, and the duty cycle of the Cr target 50 is set to 70% and the bias voltage is -100 V. Subsequently, a Cr bonding layer 10 with a thickness of 500 nm is deposited on the surface of the piezoelectric material substrate 30.

[0059] Argon gas was continued to be introduced and the ambient pressure was adjusted to 3.5 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60%, and the bias voltage was set to -100 V. An AlCrNbSiTi conductive layer with a thickness of 1 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0060] Example 2, refer to Figures 1-8 In this embodiment, the same coating preparation apparatus 200 as in Example 1 is used for preparation, and the sample 61 is mounted on the sample holder 60.

[0061] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 200 °C. Then, argon gas is introduced and the ambient pressure is controlled to 1 Pa. The bias voltage and arc power supply are turned on, and the duty cycle of the Cr target 50 is set to 60% and the bias voltage is -100V. Subsequently, a Cr bonding layer 10 with a thickness of 500 nm is deposited on the surface of the piezoelectric material substrate 30.

[0062] Argon gas was continued to be introduced and the ambient pressure was adjusted to 4 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60% and the bias voltage was set to -100 V. An AlCrNbSiTi conductive layer with a thickness of 5 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0063] The surface and cross-sectional morphology of the high-hardness, high-entropy AlCrNbSiTi composite electrode 100 of this embodiment were observed using an emission scanning electron microscope (MIRA3 TESCAN). Figure 4 It can be seen that the AlCrNbSiTi composite electrode has a dense surface, small particle size, and no obvious defects. (Reference) Figure 5 It can be seen that the AlCrNbSiTi composite electrode is tightly bonded to the piezoelectric material matrix 30 without obvious pores, indicating that the AlCrNbSiTi composite electrode has good adhesion.

[0064] The high-hardness, high-entropy AlCrNbSiTi composite electrode 100 was observed using transmission electron microscopy. (Reference) Figure 6 It can be seen that there is also a crystalline phase separating the AlCrNbSiTi amorphous phase in the AlCrNbSiTi conductive layer. The amorphous phase is drawn with circles, indicating that a nanocrystalline / amorphous nanocomposite structure is formed in the AlCrNbSiTi conductive layer.

[0065] The wear resistance of the AlCrNbSiTi conductive layer was tested using a tribometer, with reference to... Figure 7 It can be seen that the AlCrNbSiTi conductive layer showed relatively light wear after testing, indicating that the AlCrNbSiTi conductive layer has excellent wear resistance.

[0066] The high-hardness, high-entropy AlCrNbSiTi composite electrode 100 of this embodiment was annealed at 700℃, 800℃, 900℃, and 1000℃, respectively. The changes in elemental composition were then analyzed, and referenced... Figure 8 It can be seen that when the annealing temperature is 700~800℃, the loss of metal elements in the coating is minimal. When the temperature is increased to 1000℃, the matrix elements are basically undetectable in the coating, demonstrating the good chemical composition stability of the AlCrNbSiTi composite electrode.

[0067] Example 3, refer to Figures 1-3 In this embodiment, the same coating preparation apparatus 200 as in Example 1 is used for preparation, and the sample 61 is mounted on the sample holder 60.

[0068] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 150 °C. Then, argon gas is introduced and the ambient pressure is controlled to 1 Pa. The bias voltage and arc power supply are turned on, and the duty cycle of the Cr target 50 is set to 70% and the bias voltage is -50V. Subsequently, a Cr bonding layer 10 with a thickness of 500 nm is deposited on the surface of the piezoelectric material substrate 30.

[0069] Argon gas was continued to be introduced and the ambient pressure was adjusted to 3.5 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60%, and the bias voltage was set to -50 V. An AlCrNbSiTi conductive layer with a thickness of 1 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0070] Example 4, refer to Figures 1-3 In this embodiment, the same coating preparation apparatus 200 as in Example 1 is used for preparation, and the sample 61 is mounted on the sample holder 60.

[0071] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 150 °C. Then, argon gas is introduced and the ambient pressure is controlled at 0.5 Pa. The bias voltage and arc power supply are turned on, the duty cycle of the Cr target 50 is set to 60%, and the bias voltage is -100 V. Subsequently, a Cr bonding layer 10 with a thickness of 300 nm is deposited on the surface of the piezoelectric material substrate 30.

[0072] Argon gas was continued to be introduced and the ambient pressure was adjusted to 5 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60% and the bias voltage was set to -50V. An AlCrNbSiTi conductive layer with a thickness of 1 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0073] Example 5, refer to Figures 1-3 In this embodiment, the same coating preparation apparatus 200 as in Example 1 is used for preparation, and the sample 61 is mounted on the sample holder 60.

[0074] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 300 °C. Then, argon gas is introduced and the ambient pressure is controlled at 0.5 Pa. The bias voltage and arc power supply are turned on, the duty cycle of the Cr target 50 is set to 60%, and the bias voltage is -50 V. Subsequently, a Cr bonding layer 10 with a thickness of 500 nm is deposited on the surface of the piezoelectric material substrate 30.

[0075] Argon gas was continued to be introduced and the ambient pressure was adjusted to 3.5 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60%, and the bias voltage was set to -50 V. An AlCrNbSiTi conductive layer with a thickness of 3 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0076] Example 6, refer to Figures 1-3 In this embodiment, the same coating preparation apparatus 200 as in Example 1 is used for preparation, and the sample 61 is mounted on the sample holder 60.

[0077] The piezoelectric material substrate 30 is placed in the sample holder 60 of the coating preparation device 200. After the device is evacuated, the ambient temperature is raised to 150 °C. Then, argon gas is introduced and the ambient pressure is controlled at 0.5 Pa. The bias voltage and arc power supply are turned on, the duty cycle of the Cr target 50 is set to 70%, and the bias voltage is -50 V. Subsequently, a Cr bonding layer 10 with a thickness of 600 nm is deposited on the surface of the piezoelectric material substrate 30.

[0078] Argon gas was continued to be introduced and the ambient pressure was adjusted to 3.5 Pa. The power supply of Cr target 50 was turned off, and AlCrNbSiTi target 40 was used for deposition. The duty cycle of AlCrNbSiTi target 40 was set to 60%, and the bias voltage was set to -100 V. An AlCrNbSiTi conductive layer with a thickness of 8 μm was deposited on the surface of the obtained Cr bonding layer 10. After the preparation was completed, it was naturally cooled to obtain a high-hardness, high-entropy AlCrNbSiTi composite electrode 100.

[0079] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high-hardness, high-entropy AlCrNbSiTi composite electrode for bolt stress sensors, characterized in that, The high-hardness, high-entropy AlCrNbSiTi composite electrode has a gradient layer structure and includes an adhesion barrier layer and a conductive layer for bonding with piezoelectric materials. The adhesion barrier layer is a Cr bonding layer, and the conductive layer is an AlCrNbSiTi conductive layer.

2. The high-hardness, high-entropy AlCrNbSiTi composite electrode according to claim 1, characterized in that, The thickness of the adhesion barrier layer is 10~1000nm.

3. The high-hardness, high-entropy AlCrNbSiTi composite electrode according to claim 1, characterized in that, The thickness of the conductive layer is 1~20μm.

4. A method for preparing a high-hardness, high-entropy AlCrNbSiTi composite electrode according to any one of claims 1-3, characterized in that, The process employs an arc ion plating process and includes the following steps: Step (1): In an argon atmosphere, the adhesion barrier layer is deposited on the surface of the piezoelectric material substrate to form the adhesion barrier layer; Step (2): In an argon atmosphere, the conductive layer is deposited on the surface of the adhesion barrier layer to complete the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode.

5. The preparation method according to claim 4, characterized in that, During the preparation of the high-hardness, high-entropy AlCrNbSiTi composite electrode, the ambient temperature was maintained at 50~500℃.

6. The preparation method according to claim 4, characterized in that, In step (1), the deposition uses a Cr target, the arc power supply pulse duty cycle of the Cr target is 10%~80%, and the deposition bias voltage is -50~-150V.

7. The preparation method according to claim 6, characterized in that, In step (1), the atmospheric pressure for deposition is 0.1~2 Pa.

8. The preparation method according to claim 4, characterized in that, In step (2), the deposition uses an AlCrNbSiTi target, the arc power supply pulse duty cycle of the AlCrNbSiTi target is 10%-80%, and the deposition bias voltage is 0~-250V.

9. The preparation method according to claim 8, characterized in that, In step (2), the ambient pressure during deposition is 1~5 Pa.

10. The preparation method according to claim 8, characterized in that, In step (2), the deposition time is 1 to 60 minutes.

Images