Integrated co-fired stacked piezoelectric ceramic actuator and preparation method thereof

Abstract

The invention discloses an integrated co-fired stacked piezoelectric ceramic actuator and a preparation method thereof. Comprising a top insulating layer, an external negative electrode, an external negative electrode side positive electrode isolation hemisphere, a side insulating layer, a bottom insulating layer, an external negative electrode lead, an external positive electrode, an external positive electrode side negative electrode isolation hemisphere, an external positive electrode lead, an internal positive electrode layer, an internal negative electrode layer, a piezoelectric dielectric layer and a protective layer wrapping the whole ceramic. The preparation method comprises the following steps: mixing piezoelectric ceramic material lead zirconate titanate powder with ethanol, acetone, isopropanol, alcohol, isopropanol, dibutyl ester and silicone oil in proportion to obtain a mixture; stirring and grinding the mixture through a ball mill to form ceramic slurry; carrying out tape casting on the ceramic slurry to generate a ceramic material membrane; putting into a printing machine for printing to obtain a ceramic diaphragm containing an electrode surface; and performing overprinting, static pressing and sintering treatment on the ceramic diaphragm containing the electrode surface to obtain the integrated co-fired stacked piezoelectric ceramic actuator.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric ceramics, and in particular to an integral co-fired stacked piezoelectric ceramic actuator and a preparation method thereof. Background Art

[0002] Silver palladium paste or other metal material paste is printed on the surface of a piezoelectric ceramic material (PZT) film with a thickness of 10 to 500 microns and dried to form a positive electrode. Then a layer of piezoelectric ceramic (PZT) material film with a thickness of 10 to 500 microns is placed. After hot pressing and bonding, silver palladium paste or other metal material paste is printed on the surface of the bonded piezoelectric ceramic film and dried to form a negative electrode. The layers are stacked in the order described above to 400 layers or more. The stacking height is between 40 mm and 50 mm and warm isostatic pressing is performed. After pressing, the layers are cut into squares and placed in a high-temperature furnace for sintering and grinding according to a certain gradient. After grooving, the grooves are filled with insulating materials, and silver material wiring electrodes are printed on the electrode ends on both sides. After the piezoelectric ceramic is polarized, voltage is applied to the positive and negative electrodes. The piezoelectric body is affected by the electric field, the piezoelectric ceramic produces internal electric domain movement, and the piezoelectric ceramic outputs displacement. The applied voltage and the displacement output by the stacked piezoelectric ceramic are close to a linear relationship, thereby realizing micro-nano motion control.

[0003] The existing large-stroke stacked piezoelectric ceramic actuator is an interdigitated finger structure with a thickness of 3 mm. Multiple 3mm ceramics are bonded in series. There is no overlap of positive and negative electrodes at the edge of the interdigitated finger structure inside the ceramic. During operation, there is no electric field and no piezoelectric deformation occurs. Internal stress is generated between deformation and non-deformation, causing damage to the ceramic during long-term use, reducing the service life of the ceramic. The bonding part cannot be used in a vacuum due to the colloidal structure. Since the dimensions of bonding and grinding cannot be absolutely consistent, the output displacement straightness is poor, and there is an angle at the output end, affecting the output control accuracy. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an integrated co-fired stacked piezoelectric ceramic actuator and a preparation method thereof, change the internal electrode structure of the stacked piezoelectric ceramic actuator, change the interdigitated electrode into a fully effective electrode, and co-fire it as one, thereby improving the service life and output straightness of the integrated co-fired stacked piezoelectric ceramic actuator and eliminating the angular deviation phenomenon of the output displacement.

[0005] In order to solve the above technical problems, the first aspect of the embodiment of the present invention discloses an integral co-fired stacked piezoelectric ceramic actuator, including a top insulating layer 1, an external negative electrode 2, an external negative electrode side positive electrode isolation hemisphere 3, a side insulating layer 4, a bottom insulating layer 5, an external negative electrode lead 6, an external positive electrode 7, an external positive electrode side negative electrode isolation hemisphere 8, an external positive electrode lead 9, an internal positive electrode layer 10, an internal negative electrode layer 11, a piezoelectric dielectric layer 12 and a protective layer 13 that wraps the entire ceramic;

[0006] The top insulating layer 1 is located above the piezoelectric ceramic actuator; the bottom insulating layer 5 is located below the piezoelectric ceramic actuator; the top insulating layer 1 and the bottom insulating layer 5 are used to be fixed to the external device and isolate the electrodes from the conductive surface of the device at the installation location;

[0007] The side insulating layer 4 is a solid layer structure with no electrode layer inside. It is divided into two opposite outer sides on the left and right, and is used to ignite between the positive and negative electrode layers inside the sealed piezoelectric ceramic actuator in the air.

[0008] The external negative electrode 2 is located on the side of the negative electrode; the external positive electrode 7 is located on the side of the positive electrode;

[0009] The external negative electrode 2 and the external positive electrode 7 are distributed on two sides of the piezoelectric ceramic actuator and are in opposite directions;

[0010] The positive electrode side is a sintered silver layer connection structure, and each group of positive electrode layers 10 in the connection structure is internally connected in parallel through the positive electrode side;

[0011] The negative electrode side is a sintered silver layer connection structure; each group of negative electrode layers 11 in the connection structure is internally connected in parallel through the negative electrode side;

[0012] The positive electrode layer 10 is an internal positive electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute the positrons on the piezoelectric dielectric layer;

[0013] The piezoelectric dielectric layer 12 is a thin layer with piezoelectric properties. The material is a perovskite structure composed of lead zirconate titanate. When a uniform electric field is applied to the upper and lower surfaces of the piezoelectric dielectric layer, the piezoelectric dielectric layer 12 produces a piezoelectric effect, and produces different deformations according to the magnitude of the voltage.

[0014] The negative electrode layer 11 is an internal negative electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute negative electrons on the piezoelectric dielectric layer;

[0015] The external positive electrode lead 9 and the internal positive electrode layer 10 are welded with solder paste or bonded with conductive glue. The welding or bonding points are the top and bottom insulating parts of the piezoelectric ceramic actuator, which are used to prevent the piezoelectric ceramic actuator from deforming and pulling the external positive and negative electrode wires under the action of the electric field.

[0016] As an optional implementation, in the first aspect of the embodiment of the present invention, the material of the side insulating layer 4 is the material of the piezoelectric ceramic actuator body, which is a non-metallic insulating material;

[0017] The non-metallic insulating material includes insulating varnish, silicon oxide, silicon carbide and aluminum oxide.

[0018] As an optional embodiment, in the first aspect of the embodiment of the present invention, the external negative electrode 2 and the external positive electrode 7 are S-shaped structures, triangular structures, trapezoidal structures, or curved structures, and the electrodes extend to two-thirds of the length of the top insulating layer or the bottom insulating layer.

[0019] As an optional embodiment, in the first aspect of the embodiment of the present invention, the external negative-side positive electrode isolation hemisphere 3 and the external positive-side negative electrode isolation hemisphere 8 are isolation ends of the positive and negative electrode end surfaces, and are hemispherical structures, rectangular structures, triangular structures, trapezoidal structures, or curved structures;

[0020] The filling material of the external negative electrode side positive electrode isolation hemisphere 3 and the external positive electrode side negative electrode isolation hemisphere 8 is a non-metallic insulating material;

[0021] The non-metallic insulating material includes silicon oxide, silicon carbide, quartz and high temperature glue.

[0022] As an optional implementation, in the first aspect of the embodiment of the present invention, the thickness of the protective layer 13 wrapping the entire ceramic is less than 10 microns, the material is a non-metallic insulating material, and the construction method is spraying or magnetron sputtering.

[0023] A second aspect of an embodiment of the present invention discloses a method for preparing an integral co-fired stacked piezoelectric ceramic actuator, the method comprising:

[0024] S1, mixing lead zirconate titanate powder, a piezoelectric ceramic material, with ethanol, acetone, isopropyl alcohol, alcohol, isopropyl alcohol, dibutyl ester, and silicone oil in proportion to obtain a mixture;

[0025] S2, grinding the mixture with a ball mill to form a ceramic slurry;

[0026] S3, placing the ceramic slurry into a vacuum tank to remove bubbles in the ceramic slurry;

[0027] S4, introducing inert gas into the vacuum tank to push the ceramic slurry into the casting head of the casting machine, setting the casting thickness and drying step temperature, and producing a ceramic material membrane;

[0028] S5, placing the ceramic material membrane into a printing machine for printing to obtain a ceramic membrane containing an electrode surface;

[0029] S6, after inspecting and cutting the ceramic diaphragm with the electrode surface, placing it in a cavity laminating machine for lamination and hot pressing to obtain a laminated ceramic block;

[0030] S7, placing the overprinted ceramic block into a warm isostatic press to obtain a statically pressed ceramic block;

[0031] S8, cutting the statically pressed ceramic block to obtain a rectangular parallelepiped ceramic block;

[0032] S9, placing the rectangular parallelepiped ceramic block into a sintering furnace for debinding and sintering to obtain an integral co-fired piezoelectric ceramic actuator blank;

[0033] S10, grinding the integral co-fired piezoelectric ceramic actuator blank to obtain an integral co-fired stacked piezoelectric ceramic actuator.

[0034] As an optional implementation, in the second aspect of the embodiment of the present invention, the thickness of the ceramic material diaphragm is between 10 microns and 500 microns, and the thickness of the ceramic material diaphragm is set by selecting the driving voltage.

[0035] As an optional implementation, in the second aspect of the embodiment of the present invention, the printing method of the printing machine is screen printing or spray printing;

[0036] The printer prints silver-palladium slurry onto a ceramic material membrane with a printing thickness between 1 and 30 microns. After printing is completed, a gradient temperature is set to dry the electrode to form a ceramic membrane containing an electrode surface. The electrode material is a metal slurry; the metal slurry includes silver-palladium slurry, copper-nickel slurry, platinum slurry and gold slurry.

[0037] This is an optional implementation method. In the second aspect of the embodiment of the present invention, the laminate is hot-pressed so that the electrode surface of the ceramic diaphragm containing the electrode surface is in contact with the electrode-free surface, ensuring that the two ceramic diaphragms are hot-pressed and bonded together with a layer of silver-palladium electrode, and the laminate height is between 5 mm and 50 mm.

[0038] As an optional implementation, in the second aspect of the embodiment of the present invention, the upper and lower ends of the stacked ceramic blocks are pressed together to form an electrodeless ceramic diaphragm; and a refractory material is added to the electrodeless ceramic diaphragm.

[0039] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0040] The present invention features a simple, compact structure and is easy to manufacture, addressing shortcomings of piezoelectric ceramic electrode terminals, such as low stiffness, low shear force, and low tensile force. When a driving voltage is applied to the positive and negative outer electrodes of the laminated piezoelectric ceramic, an electric field is generated within the piezoelectric ceramic material between the alternating electrodes. This generates a negative piezoelectric effect within the piezoelectric ceramic, causing deformation equal to the n layers multiplied by the piezoelectric coefficient of one piezoelectric film. Driven by different voltages, the device can output displacements of a few micrometers, tens of micrometers, or hundreds of micrometers. It has been successfully applied to the design of micro- and nano-motion platforms. Adding a strain gauge feedback sensor enables high-precision micro- and nano-motion control. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 Schematic diagram of the finger-interpolation structure of the existing large-stroke stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0043] Figure 2 This is a front view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0044] Figure 3 This is a left side view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0045] Figure 4 This is a bottom view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0046] Figure 5 This is a first cross-sectional view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0047] Figure 6 is a second cross-sectional view of the integral co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention;

[0048] Figure 7 This is a schematic diagram of positioning a ceramic blank disclosed in an embodiment of the present invention;

[0049] Figure 8 Schematic diagram of concave groove processing disclosed in an embodiment of the present invention;

[0050] Figure 9 This is a schematic diagram of convex groove processing disclosed in an embodiment of the present invention;

[0051] Figure 10 It is a concave trapezoidal structure disclosed in an embodiment of the present invention;

[0052] Figure 11 It is a convex trapezoidal structure disclosed in an embodiment of the present invention;

[0053] Figure 12 It is a concave rectangular structure disclosed in an embodiment of the present invention;

[0054] Figure 13 It is a convex rectangular structure disclosed in an embodiment of the present invention;

[0055] Figure 14 It is the concave triangle structure disclosed in the embodiment of the present invention;

[0056] Figure 15 It is a convex triangular structure disclosed in an embodiment of the present invention;

[0057] Figure 16 It is a concave curved structure disclosed in an embodiment of the present invention;

[0058] Figure 17 It is a convex curved structure disclosed in an embodiment of the present invention;

[0059] Figure 18 This is the method of processing electrode leads on opposite surfaces disclosed in the embodiment of the present invention;

[0060] Figure 19 This is the method of processing electrode leads on adjacent surfaces disclosed in the embodiment of the present invention;

[0061] Figure 20 This is the same-surface electrode lead processing method disclosed in the embodiment of the present invention;

[0062] Figure 21 This is the result of the piezoelectric ceramic actuator disclosed in the embodiment of the present invention when it is controlled by DC (direct current) 0V voltage;

[0063] Figure 22 This is the result of the piezoelectric ceramic actuator disclosed in the embodiment of the present invention when controlled by a DC (direct current) voltage of 150V;

[0064] Figure 23 The embodiment of the present invention discloses a piezoelectric ceramic actuator controlling a DC (direct current) 0V to 150V negative boost displacement output and a 150V to 0V buck displacement output curve;

[0065] Figure 24 The output result of the piezoelectric ceramic actuator disclosed in the embodiment of the present invention is when the AC (alternating current) peak-to-peak voltage is 120V;

[0066] Figure 25 It is a schematic flow chart of a method for preparing an integral co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0067] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0068] The terms "first," "second," and so on, in the description and claims of the present invention and the accompanying drawings are used to distinguish between different objects, not to describe a specific order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product, or device comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or device.

[0069] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0070] The present invention discloses an integrated co-fired stacked piezoelectric ceramic actuator and its preparation method, comprising a top insulating layer, an external negative electrode, an external negative electrode side positive electrode isolation hemisphere, side insulating layers, a bottom insulating layer, an external negative electrode lead, an external positive electrode, an external positive electrode side negative electrode isolation hemisphere, an external positive electrode lead, an internal positive electrode layer, an internal negative electrode layer, a piezoelectric dielectric layer, and a protective layer surrounding the entire ceramic. The piezoelectric ceramic material lead zirconate titanate powder is mixed with ethanol, acetone, isopropyl alcohol, alcohol, isopropyl alcohol, dibutyl ester, and silicone oil in a proportioned manner to obtain a mixture; the mixture is stirred and ground in a ball mill to form a ceramic slurry; the ceramic slurry is formed into a ceramic material diaphragm; the ceramic diaphragm is placed in a printer for printing to obtain a ceramic diaphragm containing an electrode surface; and the ceramic diaphragm containing an electrode surface is processed to obtain the integrated co-fired stacked piezoelectric ceramic actuator. Each of the steps is described in detail below.

[0071] Figure 1 This is a schematic diagram of the finger structure of the existing large-stroke stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention; the existing large-stroke stacked piezoelectric ceramic actuator is a finger structure with a specification thickness of 3 mm. Multiple 3mm ceramics are bonded in series. The positive and negative electrodes inside the ceramic have no overlap at the edge of the finger structure. During operation, there is no electric field and no piezoelectric deformation occurs. Internal stress is generated between deformation and non-deformation, causing damage to the ceramic during long-term use, reducing the service life of the ceramic. The bonding part cannot be used in a vacuum due to the colloidal structure. Since the dimensions of bonding and grinding cannot be absolutely consistent, the output displacement straightness is poor, and there is an angle at the output end, affecting the output control accuracy.

[0072] Figure 1As shown, a: output part 1 without electric field and displacement; b: output part 2 without electric field and displacement; c: bonding section; d: output part with displacement under electric field action; since parts a and b have no positive and negative electric field action, they cannot deform, and there is stress due to internal output deformation, which will cause cracking during long-term operation and lead to damage, reducing the service life. Part c is bonded with glue, resulting in insufficient output accuracy and cannot be used in a vacuum.

[0073] Example 1

[0074] See also Figure 2 , Figure 2 This is a front view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention. Figure 2 The described integrated co-fired stacked piezoelectric ceramic actuator is applied to the field of piezoelectric ceramic technology, and the embodiments of the present invention do not limit this. Figure 2 As shown, the integrated co-fired stacked piezoelectric ceramic actuator includes a top insulating layer 1, an external negative electrode 2, an external negative electrode side positive electrode isolation hemisphere 3, a side insulating layer 4, a bottom insulating layer 5, an external negative electrode lead 6, an external positive electrode 7, an external positive electrode side negative electrode isolation hemisphere 8, an external positive electrode lead 9, an internal positive electrode layer 10, an internal negative electrode layer 11, a piezoelectric dielectric layer 12, and a protective layer 13 that wraps the entire ceramic;

[0075] The top insulating layer 1 is located above the piezoelectric ceramic actuator; the bottom insulating layer 5 is located below the piezoelectric ceramic actuator; the top insulating layer 1 and the bottom insulating layer 5 are used to be fixed to the external device and isolate the electrodes from the conductive surface of the device at the installation location;

[0076] The side insulating layer 4 is a solid layer structure with no electrode layer inside. It is divided into two opposite outer sides on the left and right, and is used to ignite the positive and negative electrode layers inside the sealed piezoelectric ceramic actuator in the air. Because the piezoelectric dielectric layer between the positive and negative electrodes is only tens to hundreds of microns thick, if there is no side insulating layer, the positive and negative adjacent electrode layers are exposed to the air. When the voltage is very high, an arc will be generated and the ceramic will be burned. The external insulating layer can provide the overall stiffness and tensile strength of the piezoelectric ceramic actuator.

[0077] The external negative electrode 2 is located on the side of the negative electrode; the external positive electrode 7 is located on the side of the positive electrode;

[0078] The external negative electrode 2 and the external positive electrode 7 are distributed on two sides of the piezoelectric ceramic actuator and are in opposite directions;

[0079] The positive electrode side is a sintered silver layer connection structure, and each group of positive electrode layers 10 in the connection structure is internally connected in parallel through the positive electrode side;

[0080] The negative electrode side is a sintered silver layer connection structure; each group of negative electrode layers 11 in the connection structure is internally connected in parallel through the negative electrode side;

[0081] The positive electrode layer 10 is an internal positive electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute the positrons on the piezoelectric dielectric layer;

[0082] The piezoelectric dielectric layer 12 is a thin layer with piezoelectric properties. The material is a perovskite structure composed of lead zirconate titanate. When a uniform electric field is applied to the upper and lower surfaces of the piezoelectric dielectric layer, the piezoelectric dielectric layer 12 produces a piezoelectric effect, and produces different deformations according to the magnitude of the voltage.

[0083] The negative electrode layer 11 is an internal negative electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute negative electrons on the piezoelectric dielectric layer;

[0084] The external positive electrode lead 9 and the internal positive electrode layer 10 are welded with solder paste or bonded with conductive glue. The welding or bonding points are the top and bottom insulating parts of the piezoelectric ceramic actuator, which are used to prevent the piezoelectric ceramic actuator from deforming and pulling the external positive and negative electrode wires under the action of the electric field.

[0085] The integrally co-fired stacked piezoelectric ceramic actuator of the present invention is referred to as a piezoelectric ceramic actuator for short.

[0086] Figure 3 This is a left side view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention; Figure 4 This is a bottom view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention.

[0087] Figure 5 This is a first cross-sectional view of the integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention; Figure 5 In the figure, 2-A: S-shaped external negative electrode; 3-A: external convex negative electrode isolation hemisphere; 7-A: S-shaped external positive electrode; 8-A: external convex positive electrode isolation hemisphere. The first cross-sectional view shows the first internal structure, which is an external convex structure.

[0088] Figure 6 is a second cross-sectional view of the integral co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention; Figure 6 In the figure, 2-B: small S-shaped external negative electrode; 3-B: external concave negative electrode isolation hemisphere; 7-B: small S-shaped external positive electrode; 8-B: external concave positive electrode isolation hemisphere. The second cross-sectional view shows the second internal structure, which is a concave structure.

[0089] Optionally, the material of the side insulating layer 4 is the material of the piezoelectric ceramic actuator body, which is a non-metallic insulating material;

[0090] The non-metallic insulating material includes insulating varnish, silicon oxide, silicon carbide and aluminum oxide.

[0091] Optionally, the external negative electrode 2 and the external positive electrode 7 have an S-shaped, triangular, trapezoidal, or curved structure, and extend to two-thirds of the length of the top insulating layer or the bottom insulating layer. The extended portion has space for welding or gluing external leads. When the piezoelectric ceramic actuator deforms under the action of an electric field, this structure can deform to eliminate deformation stress, thereby eliminating fatigue damage to the external negative electrode 2 and the external positive electrode 7.

[0092] Optionally, the external negative electrode side positive electrode isolation hemisphere 3 and the external positive electrode side negative electrode isolation hemisphere 8 are isolation ends of the positive and negative electrode end surfaces, and are hemispherical structures, rectangular structures, triangular structures, trapezoidal structures, or curved structures;

[0093] The filling material of the external negative electrode side positive electrode isolation hemisphere 3 and the external positive electrode side negative electrode isolation hemisphere 8 is a non-metallic insulating material;

[0094] The non-metallic insulating material includes silicon oxide, silicon carbide, quartz and high temperature glue.

[0095] Optionally, the protective layer 13 covering the entire ceramic has a thickness of less than 10 microns, is made of non-metallic insulating material, and is applied by spraying or magnetron sputtering. The protective layer covering the entire ceramic has a moisture-proof function.

[0096] Example 2

[0097] See also Figure 25 , Figure 25 This is a flow chart of the method for preparing an integrated co-fired stacked piezoelectric ceramic actuator disclosed in an embodiment of the present invention. Figure 25 The method for preparing the integrated co-fired stacked piezoelectric ceramic actuator described above is applicable to the field of piezoelectric ceramic technology and is not limited in the embodiments of the present invention. Figure 25 As shown, the method for preparing the integrated co-fired stacked piezoelectric ceramic actuator includes:

[0098] S1, mixing lead zirconate titanate powder, a piezoelectric ceramic material, with ethanol, acetone, isopropyl alcohol, alcohol, isopropyl alcohol, dibutyl ester, and silicone oil in proportion to obtain a mixture;

[0099] The ratio is a ratio preset according to needs;

[0100] S2, grinding the mixture with a ball mill to form a ceramic slurry;

[0101] S3, placing the ceramic slurry into a vacuum tank to remove bubbles in the ceramic slurry;

[0102] S4, introducing inert gas into the vacuum tank to push the ceramic slurry into the casting head of the casting machine, setting the casting thickness and drying step temperature, and producing a ceramic material membrane;

[0103] S5, placing the ceramic material membrane into a printing machine for printing to obtain a ceramic membrane containing an electrode surface;

[0104] S6, after inspecting and cutting the ceramic diaphragm with the electrode surface, placing it in a cavity laminating machine for lamination and hot pressing to obtain a laminated ceramic block;

[0105] S7, placing the overprinted ceramic block into a warm isostatic press to obtain a statically pressed ceramic block;

[0106] The role of static pressure is to increase density;

[0107] S8, cutting the statically pressed ceramic block to obtain a rectangular parallelepiped ceramic block;

[0108] S9, placing the rectangular parallelepiped ceramic block into a sintering furnace for debinding and sintering to obtain an integral co-fired piezoelectric ceramic actuator blank;

[0109] The hot pressing temperature is 60 to 85 degrees, and the pressure is 30 to 200Mpa. After the hot pressing is completed, it is cut into 4×4, 6×6, 8×8, and 12×12 unit millimeter rectangles as required, and placed in the sintering furnace for debinding and sintering. The sintering time is more than 168 hours.

[0110] S10, grinding the integral co-fired piezoelectric ceramic actuator blank to obtain an integral co-fired stacked piezoelectric ceramic actuator. 4×4, 6×6, 8×8, 12×12 ceramics are ground into 3×3, 5×5, 7×7, 10×10, or other sizes.

[0111] The internal electrode positive and negative section isolation part is made, Figure 7 Positioning ceramic blanks; Figure 8 Concave groove processing, Figure 9 Convex groove processing, Figure 8 and Figure 9 There are two processing methods: f: ceramic blank; g: processing concave groove; f: processing convex groove; e: processing fixed surface.

[0112] Optionally, the thickness of the ceramic material diaphragm is between 10 microns and 500 microns, and the thickness of the ceramic material diaphragm is set by selecting a driving voltage.

[0113] Optionally, the printing method of the printing press is screen printing or spray printing;

[0114] The printer prints silver-palladium slurry onto a ceramic material membrane with a printing thickness between 1 and 30 microns. After printing is completed, a gradient temperature is set to dry the electrode to form a ceramic membrane containing an electrode surface. The electrode material is a metal slurry; the metal slurry includes silver-palladium slurry, copper-nickel slurry, platinum slurry and gold slurry.

[0115] Optionally, the stacking is hot-pressed so that the electrode surface of the ceramic diaphragm containing the electrode surface is in contact with the electrode-free surface, ensuring that the hot-pressed bonding surfaces of the two ceramic diaphragms have a layer of silver-palladium electrode, and the stacking height is between 5 mm and 50 mm.

[0116] Optionally, an electrodeless ceramic diaphragm is pressed between the upper and lower ends of the stacked ceramic block; and a refractory material is added to the electrodeless ceramic diaphragm.

[0117] The internal electrode positive and negative cross-section isolation parts also include rectangular structures, trapezoidal structures, triangular structures, and curved structures, which are divided into convex and concave types; Figure 10 It is a concave trapezoidal structure; Figure 11 It is a convex trapezoidal structure; Figure 12 It is a concave rectangular structure; Figure 13 It is a convex rectangular structure.

[0118] Figure 14 It is a concave triangular structure; Figure 15 It is a convex triangular structure; Figure 16 It is a concave curved structure; Figure 17 It is a convex curved structure;

[0119] The ceramic blank f is mounted on the processing fixed surface e by bonding, and the g or f structure is processed by physical removal, femtosecond laser ablation, and high-precision 3D printing technology. The shapes of the internal electrode positive and negative cross-section isolation parts are divided into semicircular structures, rectangular structures, trapezoidal structures, triangular structures, and curved structures, and are divided into convex and concave types. The internal electrode positive and negative cross-section isolation is processed in three ways: opposite surface processing, adjacent surface processing, and single surface processing.

[0120] Figure 18 For the opposite surface processing electrode lead method, Figure 19 For adjacent surface processing electrode lead method, Figure 20 The electrode leads are processed on the same surface.

[0121] The cut ceramics are partially filled with isolation materials such as silicon oxide, silicon carbide, quartz, high-temperature glue and non-metallic insulating materials. The filling methods include printing, static pressing and 3D printing. The concave shape is completed by printing, static pressing and sintering; the convex shape is completed by cutting, 3D printing and sintering.

[0122] The external negative electrode 2 is cut according to the piezoelectric ceramic actuator, the filling position, two opposite surfaces or two adjacent surfaces, or the same surface, and the silver paste is screen-printed on the ceramic surface by screen printing. The screen printing makes the electrode contact with the external negative side positive electrode isolation hemisphere 3 and all internal negative electrode layers 11; and the shape of the filling isolation material is extended to form an S-shaped electrode structure or a small S-shaped electrode structure.

[0123] The external positive electrode 7 is cut according to the piezoelectric ceramic actuator, the filling position, two opposite surfaces or two adjacent surfaces, or the same surface, the silver paste is screen-printed on the ceramic surface, the screen printing separates the electrode from the external positive side negative electrode hemisphere 8; the internal positive electrode layer 10 is in contact; and the shape of the filling isolation material is extended to form an S-shaped electrode structure or a small S-shaped electrode structure.

[0124] After screen printing, the external negative electrode 2 and the external positive electrode 7 are placed in a heating furnace for sintering at a temperature of 50-800 degrees and a sintering time of 24 hours.

[0125] The side non-electrode lead-out surface needs to be treated to isolate the positive and negative internal electrodes to form a side insulating layer. The side insulating layer is screen-printed with the main material, insulating paint, silicon oxide, silicon carbide, aluminum oxide, and non-metallic insulating material on the ceramic screen. After completion, it is placed in a heating furnace and sintered at a temperature of 50-800 degrees. The sintering time is 24 hours to form a side insulating layer.

[0126] For the external negative electrode lead 6 and the external positive electrode lead 9, cut the black and red silicone wires into 150 mm lengths, remove the outer skin of the silicone wires by 2 mm at both ends, and solder the external positive and negative electrode leads with solder paste and bond them with conductive glue; the welding or bonding points are at the top of the piezoelectric ceramic actuator and two-thirds of the bottom insulating part to prevent the piezoelectric ceramic actuator from deforming and pulling the external positive and negative electrode wires under the action of the electric field.

[0127] The entire surface is sprayed with moisture-proof protective paint, glue, sprayed with nano-water-repellent coating, and magnetron sputtering moisture-proof material, with the thickness controlled within 5 microns.

[0128] As can be seen, the present invention has a simple, compact structure and is easy to produce, addressing shortcomings of the piezoelectric ceramic electrode lead-out terminals, such as low stiffness, low shear force, and low tensile force. When a driving voltage is applied to the positive and negative outer electrodes of the laminated piezoelectric ceramic, an electric field is generated in the piezoelectric ceramic material between the alternating electrodes. The n layers of piezoelectric dielectric within the laminated piezoelectric ceramic produce a negative piezoelectric effect, resulting in deformation equal to the n layers multiplied by the piezoelectric coefficient of one piezoelectric film. Driven by different voltages, the device can output displacements of a few micrometers, tens of micrometers, or hundreds of micrometers. It has been successfully applied to the design of micro-nano motion platforms. The addition of a feedback sensor enables high-precision micro-nano motion control.

[0129] Example 3

[0130] Piezoelectric ceramic actuator drive control Figure 21 、 Figure 22 As shown, 13: piezoelectric ceramic actuator, 14: voltage power amplifier, 15: piezoelectric extension of the piezoelectric ceramic actuator;

[0131] Figure 21 When the piezoelectric ceramic actuator is controlled by DC (direct current) 0V voltage, the piezoelectric ceramic actuator has no displacement output.

[0132] Figure 22 When the piezoelectric ceramic actuator is controlled by a DC (direct current) voltage of 150V, the piezoelectric ceramic actuator has a 15-degree shift output.

[0133] When the piezoelectric ceramic actuator is controlled by an AC (alternating current) peak-to-peak voltage of 120V and a sine wave frequency of 50 Hz, the piezoelectric ceramic actuator outputs a 15-degree shift output and a 50 Hz sine wave vibration.

[0134] Figure 23 The curves of the DC (direct current) 0V to 150V negative boost displacement output and the 150V to 0V buck displacement output of the piezoelectric ceramic actuator are shown.

[0135] Figure 24 This is the piezoelectric ceramic actuator output 15-degree shift output and 50 Hz sinusoidal wave vibration curve when it is controlled by AC (alternating current) peak-to-peak voltage of 120V and frequency of 50 Hz sine wave.

[0136] The device embodiments described above are merely illustrative. Modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0137] Finally, it should be noted that the integrated co-fired stacked piezoelectric ceramic actuator and its preparation method disclosed in the embodiments of the present invention are only preferred embodiments of the present invention, and are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An integrated co-fired stacked piezoelectric ceramic actuator, characterized in that: The invention comprises a top insulating layer (1), an external negative electrode (2), an external negative electrode side positive electrode isolation hemisphere (3), a side insulating layer (4), a bottom insulating layer (5), an external negative electrode lead (6), an external positive electrode (7), an external positive electrode side negative electrode isolation hemisphere (8), an external positive electrode lead (9), an internal positive electrode layer (10), an internal negative electrode layer (11), a piezoelectric dielectric layer (12) and a protective layer (13) that wraps the entire ceramic; The top insulating layer (1) is located above the piezoelectric ceramic actuator; the bottom insulating layer (5) is located below the piezoelectric ceramic actuator; the top insulating layer (1) and the bottom insulating layer (5) are used to be fixed to the external device installation surface, isolating the electrodes from the electrical conduction of the installation location device; The side insulating layer (4) is a solid layer structure, has no electrode layer inside, and is divided into two opposite outer sides on the left and right, and is used to ignite between the positive and negative electrode layers inside the sealed piezoelectric ceramic actuator in the air; The external negative electrode (2) is located on the side of the negative electrode; the external positive electrode (7) is located on the side of the positive electrode; The external negative electrode (2) and the external positive electrode (7) are distributed on two side surfaces of the piezoelectric ceramic actuator in opposite directions; The positive electrode side is a sintered silver layer connection structure, and each group of positive electrode layers (10) in the connection structure are internally connected in parallel through the positive electrode side; The negative electrode side is a sintered silver layer connection structure; each group of negative electrode layers (11) in the connection structure is internally connected in parallel through the negative electrode side; The positive electrode layer (10) is an internal positive electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute positrons on the piezoelectric dielectric layer; The piezoelectric dielectric layer (12) is a thin layer with piezoelectric properties, and its material is a perovskite structure composed of lead zirconate titanate. When a uniform electric field is applied to the upper and lower surfaces of the piezoelectric dielectric layer, the piezoelectric dielectric layer (12) generates a piezoelectric effect, and produces different deformations according to the magnitude of the voltage. The negative electrode layer (11) is an internal negative electrode, and a silver-palladium electrode is printed on the piezoelectric dielectric layer using a graphic printing plate, so as to evenly distribute negative electrons on the piezoelectric dielectric layer; The external positive electrode lead (9) and the internal positive electrode layer (10) are soldered or bonded using a conductive adhesive, and the welding or bonding points are the top and bottom insulating parts of the piezoelectric ceramic actuator, which are used to prevent the piezoelectric ceramic actuator from deforming and pulling the external positive and negative electrode wires under the action of an electric field.

2. The integral co-fired stacked piezoelectric ceramic actuator according to claim 1, characterized in that: The material of the side insulating layer (4) is the material of the piezoelectric ceramic actuator body, which is a non-metallic insulating material; The non-metallic insulating material includes insulating varnish, silicon oxide, silicon carbide and aluminum oxide.

3. The integral co-fired stacked piezoelectric ceramic actuator according to claim 1, characterized in that: The external negative electrode (2) and the external positive electrode (7) are in an S-shaped structure, a triangular structure, a trapezoidal structure or a curved structure, and the electrodes extend to two-thirds of the length of the top insulating layer or the bottom insulating layer.

4. The integral co-fired stacked piezoelectric ceramic actuator according to claim 1, characterized in that: The external negative electrode side positive electrode isolation hemisphere (3) and the external positive electrode side negative electrode isolation hemisphere (8) are the isolation ends of the positive and negative electrode end surfaces, and are hemispherical structures, triangular structures, trapezoidal structures, or curved structures; The filling material of the external negative electrode side positive electrode isolation hemisphere (3) and the external positive electrode side negative electrode isolation hemisphere (8) is a non-metallic insulating material; The non-metallic insulating material includes silicon oxide, silicon carbide, quartz and high temperature glue.

5. The integral co-fired stacked piezoelectric ceramic actuator according to claim 1, characterized in that: The thickness of the protective layer (13) wrapping the entire ceramic is less than 10 microns, the material is a non-metallic insulating material, and the construction method is spraying or magnetron sputtering.

6. A method for preparing an integral co-fired stacked piezoelectric ceramic actuator, characterized in that: Applied to the integrally co-fired stacked piezoelectric ceramic actuator according to any one of claims 1 to 5, the method comprises: S1, mixing lead zirconate titanate powder, a piezoelectric ceramic material, with ethanol, acetone, isopropyl alcohol, alcohol, isopropyl alcohol, dibutyl ester, and silicone oil in proportion to obtain a mixture; S2, grinding the mixture with a ball mill to form a ceramic slurry; S3, placing the ceramic slurry into a vacuum tank to remove bubbles in the ceramic slurry; S4, introducing inert gas into the vacuum tank to push the ceramic slurry into the casting head of the casting machine, setting the casting thickness and drying step temperature, and producing a ceramic material membrane; S5, placing the ceramic material membrane into a printing machine for printing to obtain a ceramic membrane containing an electrode surface; S6, after inspecting and cutting the ceramic diaphragm with the electrode surface, placing it in a cavity laminating machine for lamination and hot pressing to obtain a laminated ceramic block; S7, placing the overprinted ceramic block into a warm isostatic press to obtain a statically pressed ceramic block; S8, cutting the statically pressed ceramic block to obtain a rectangular parallelepiped ceramic block; S9, placing the rectangular parallelepiped ceramic block into a sintering furnace for debinding and sintering to obtain an integral co-fired piezoelectric ceramic actuator blank; S10, grinding the integral co-fired piezoelectric ceramic actuator blank to obtain an integral co-fired stacked piezoelectric ceramic actuator.

7. The method for preparing an integrally co-fired stacked piezoelectric ceramic actuator according to claim 6, wherein: The thickness of the ceramic material diaphragm is between 10 microns and 500 microns, and the thickness of the ceramic material diaphragm is set by selecting the driving voltage.

8. The method for preparing an integrally co-fired stacked piezoelectric ceramic actuator according to claim 6, wherein: The printing method of the printing press is screen printing or spray printing; The printer prints silver-palladium slurry onto a ceramic material membrane with a printing thickness between 1 and 30 microns. After printing is completed, a gradient temperature is set to dry the electrode to form a ceramic membrane containing an electrode surface. The electrode material is a metal slurry; the metal slurry includes silver-palladium slurry, copper-nickel slurry, platinum slurry and gold slurry.

9. The method for preparing an integrally co-fired stacked piezoelectric ceramic actuator according to claim 6, wherein: The stacking hot pressing is carried out so that the electrode surface of the ceramic diaphragm containing the electrode surface contacts the electrode-free surface, ensuring that the hot-pressed bonding surfaces of the two ceramic diaphragms have a layer of silver-palladium electrode, and the stacking height is between 5mm and 50mm.

10. The method for preparing an integrally co-fired stacked piezoelectric ceramic actuator according to claim 6, wherein: The upper and lower ends of the stacked ceramic blocks are pressed together to form an electrodeless ceramic diaphragm; and a sinter-resistant material is added to the electrodeless ceramic diaphragm.

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