阅读说明：本技术 一种pzt基高居里温度压电陶瓷及制备方法 (PZT-based high Curie temperature piezoelectric ceramic and preparation method thereof ) 是由 盖学周 李伟 吴凡 于 2020-07-14 设计创作，主要内容包括：本发明公开了一种PZT基高居里温度压电陶瓷及制备方法,包括以下重量份数的原料：四氧化三铅100份、二氧化锆26-28份、二氧化钛15-17份、五氧化二铌2.0-4.0份、碳酸锂0.1-0.2份。经LiNb0<Sub>3</Sub>合成、混料、预烧、造粒、成型及排塑、烧结、上电极、极化、测量制备而成。通过在PZT中引入高居里温度LiNb0<Sub>3</Sub>组分,进一步提高了PZT基压电陶瓷的居里温度Tc,拓展了压电陶瓷在极端环境下的应用。(The invention discloses PZT-based high Curie temperature piezoelectric ceramic and a preparation method thereof, wherein the PZT-based high Curie temperature piezoelectric ceramic comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-4.0 parts of niobium pentoxide and 0.1-0.2 part of lithium carbonate. From LiNb0 3 Synthesizing, mixing, presintering, granulating, molding, plastic discharging, sintering, electrode mounting, polarizing and measuring. By introducing high Curie temperature LiNb0 in PZT 3 The components further improve the Curie temperature Tc of the PZT-based piezoelectric ceramic, and expand the application of the piezoelectric ceramic in extreme environments.)

1. A PZT-based high Curie temperature piezoelectric ceramic, characterized in that: the composite material comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide and 0.1-0.2 part of lithium carbonate.

2. A PZT-based high curie temperature piezoelectric ceramic according to claim 1, wherein: the composite material comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide, 0.1-0.2 part of lithium carbonate and 0.01-0.1 part of antimony trioxide.

3. A method for preparing a PZT-based high curie temperature piezoelectric ceramic according to claim 1, comprising the steps of:

1)LiNb0₃synthesizing: baking lithium carbonate and niobium pentoxide at the temperature of 120-130 ℃ for 12 hours, then carrying out dry mixing and ball milling, keeping the temperature of the uniformly mixed materials at the temperature of 1000-1100 ℃ for 4 hours, and synthesizing LiNb0₃；

2) Mixing materials: the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide and titanium dioxide into a roller mill, mixing for 18 hours by a wet method, and discharging slurry after fully and uniformly mixing;

3) pre-burning: drying the mixed slurry, pressing the slurry into blocks, placing the blocks into an alumina crucible, and presintering and synthesizing the blocks in a tunnel type pushed slab kiln at the presintering temperature of 860-880 ℃ for 2 hours;

4) and (3) granulation: crushing the pre-sintered material blocks, then placing the crushed material blocks into a stirring mill for stirring and fine milling, wherein the raw materials in weight ratio during stirring are as follows: zirconium ball: pure water 1: 2: stirring for 3 hours, adding 3-7 wt% of polyvinyl alcohol binder, continuously stirring for 0.5 hour, and then granulating in a spray tower;

5) molding and plastic removal: preparing a blank body with the diameter of 25 multiplied by 2.5-2.8 mm from the granulated powder through a dry pressing forming method; keeping the molded blank at the temperature of 750-850 ℃ for 2-5 hours to remove the glue;

6) and (3) sintering: sealing and sintering at 1270-1310 ℃, and keeping the temperature for 2 h;

7) an upper electrode: after the porcelain piece is sintered, the main plane is coated with a silver electrode after grinding, cleaning and drying, then the porcelain piece is placed in a heating furnace, the temperature is raised to 750 ℃, the heat is preserved for 30 minutes, and the porcelain piece is naturally cooled to room temperature;

8) polarization: and (3) polarizing the electrode sample in silicone oil at the temperature of 130-140 ℃ by applying a direct current electric field of 2.0-2.5 kv/mm.

4. The method for preparing a PZT-based high curie temperature piezoelectric ceramic according to claim 3, wherein in the step 2), the materials are mixed: the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide, titanium dioxide and antimony trioxide into a roller mill, mixing for 18 hours by a wet method, fully mixing uniformly, and discharging slurry.

Technical Field

The invention relates to piezoelectric ceramics, in particular to PZT-based high Curie temperature piezoelectric ceramics and a preparation method thereof, which are mainly applied to the aspects of petroleum logging, automobile piezoelectric ceramic drivers and the like and belong to the technical field of electronic component manufacturing.

Background

The PZT piezoelectric ceramic is made of ferroelectric PbTi0₃With antiferroelectric PbZr0₃The formed continuous solid solution, PZT due to excellent piezoelectric and dielectric propertiesPiezoelectric ceramics always occupy the main application market of piezoelectric ceramics, and become the most popular piezoelectric ceramics in commercialization; however, the Curie temperature Tc of the PZT piezoelectric ceramic is generally low (150-360 ℃), so that the application of the PZT piezoelectric ceramic in a high-temperature environment is limited.

In recent years, with the further expansion of the application range of piezoelectric ceramics, new challenges are provided for the service performance of piezoelectric ceramics in some extreme environments, for example, in the field of oil exploration, in the drilling process, a probe sensor needs to acquire data of temperature, pressure, flow and the like of the surrounding environment, and the ambient temperature near the probe can change in a wide range, which requires that the relevant piezoelectric sensor can bear higher temperature. Compared with the conventional PZT piezoelectric ceramics, the piezoelectric ceramics for acoustic logging has the characteristics that: firstly, the performance is stable under the conditions of high temperature and high pressure, so that the sensor can be ensured to adapt to the high-temperature and high-pressure environment of an oil well; secondly, high transmission power, sensitivity, frequency consistency and the like need to be maintained under the environment, so that the requirements of good measurement accuracy and measurement efficiency can be met.

In addition, the fuel injector in the current advanced automobile electronic fuel injection system generally adopts a piezoelectric fuel injector, and compared with the traditional mechanical carburetor, the electronic control gasoline injection system can improve the power of an automobile engine by 5-10 percent, reduce the consumption rate of gasoline by 5-10 percent and reduce the exhaust emission by 20 percent; the piezoelectric ceramic driver in the piezoelectric type oil sprayer in the market mostly adopts the conventional PZT piezoelectric ceramic, the safe use temperature is only below 150 ℃, if the service temperature of the piezoelectric ceramic exceeds 1/2Tc, the piezoelectric ceramic can be seriously depolarized, and the performance of the piezoelectric ceramic is reduced or even loses the piezoelectric performance;

disclosure of Invention

The invention aims to overcome the defects in the prior art and provides PZT-based high-Curie-temperature piezoelectric ceramic and a preparation method thereof.

The object of the present invention is achieved by the following technical means. A PZT-based high Curie temperature piezoelectric ceramic comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide and 0.1-0.2 part of lithium carbonate.

Furthermore, the feed comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide, 0.1-0.2 part of lithium carbonate and 0.01-0.1 part of antimony trioxide.

The invention discloses a preparation method of PZT-based high Curie temperature piezoelectric ceramics, which comprises the following preparation steps:

1)LiNb0₃synthesizing: baking lithium carbonate and niobium pentoxide at the temperature of 120-130 ℃ for 12 hours, then carrying out dry mixing and ball milling, keeping the temperature of the uniformly mixed materials at the temperature of 1000-1100 ℃ for 4 hours, and synthesizing LiNb0₃；

2) Mixing materials: the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide and titanium dioxide into a roller mill, mixing for 18 hours by a wet method, and discharging slurry after fully and uniformly mixing;

3) pre-burning: drying the mixed slurry, pressing the slurry into blocks, placing the blocks into an alumina crucible, and presintering and synthesizing the blocks in a tunnel type pushed slab kiln at the presintering temperature of 860-880 ℃ for 2 hours;

4) and (3) granulation: crushing the pre-sintered material blocks, then placing the crushed material blocks into a stirring mill for stirring and fine milling, wherein the raw materials in weight ratio during stirring are as follows: zirconium ball: pure water 1: 2: stirring for 3 hours, adding 3-7 wt% of polyvinyl alcohol binder, continuously stirring for 0.5 hour, and then granulating in a spray tower;

5) molding and plastic removal: preparing a blank body with the diameter of 25 multiplied by 2.5-2.8 mm from the granulated powder through a dry pressing forming method; keeping the molded blank at the temperature of 750-850 ℃ for 2-5 hours to remove the glue;

6) and (3) sintering: sealing and sintering at 1270-1310 ℃, and keeping the temperature for 2 h;

7) an upper electrode: after the porcelain piece is sintered, the main plane is coated with a silver electrode after grinding, cleaning and drying, then the porcelain piece is placed in a heating furnace, the temperature is raised to 750 ℃, the heat is preserved for 30 minutes, and the porcelain piece is naturally cooled to room temperature;

8) polarization: and (3) polarizing the electrode sample in silicone oil at the temperature of 130-140 ℃ by applying a direct current electric field of 2.0-2.5 kv/mm.

Further, in step 2), mixing: the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide, titanium dioxide and antimony trioxide into a roller mill, mixing for 18 hours by a wet method, fully mixing uniformly, and discharging slurry.

The invention has the beneficial effects that: a PZT-based piezoelectric ceramic having a high Curie temperature and good overall electrical properties is provided by introducing LiNb0 having a high Curie temperature into PZT₃The components further improve the Curie temperature Tc of the PZT-based piezoelectric ceramic, and expand the application of the piezoelectric ceramic in extreme environments.

Drawings

FIG. 1 is a medium temperature map of examples 1, 2 and 3 of the present invention;

FIG. 2 is a SEM image of a natural section in example 1 of the present invention;

FIG. 3 is a SEM image of a natural section in example 2 of the present invention;

FIG. 4 is a SEM image of a natural section in example 3 of the present invention.

Detailed Description

The invention will be described in detail with reference to the following figures and examples:

the invention discloses a PZT-based high Curie temperature piezoelectric ceramic, which comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide and 0.1-0.2 part of lithium carbonate.

Furthermore, the feed comprises the following raw materials in parts by weight: 100 parts of lead tetraoxide, 26-28 parts of zirconium dioxide, 15-17 parts of titanium dioxide, 2.0-3.0 parts of niobium pentoxide, 0.1-0.2 part of lithium carbonate and 0.01-0.1 part of antimony trioxide.

The invention discloses a preparation method of PZT-based high Curie temperature piezoelectric ceramics, which comprises the following preparation steps:

1)LiNb0₃synthesizing: baking lithium carbonate and niobium pentoxide at the temperature of 120-130 ℃ for 12 hours, then carrying out dry mixing and ball milling, keeping the temperature of the uniformly mixed materials at the temperature of 1000-1100 ℃ for 4 hours, and synthesizing LiNb0₃；

2) Mixing materials:the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide and titanium dioxide into a roller mill, mixing for 18 hours by a wet method, and discharging slurry after fully and uniformly mixing;

3) pre-burning: drying the mixed slurry, pressing the slurry into blocks, placing the blocks into an alumina crucible, and presintering and synthesizing the blocks in a tunnel type pushed slab kiln at the presintering temperature of 860-880 ℃ for 2 hours;

4) and (3) granulation: crushing the pre-sintered material blocks, then placing the crushed material blocks into a stirring mill for stirring and fine milling, wherein the raw materials in weight ratio during stirring are as follows: zirconium ball: pure water 1: 2: stirring for 3 hours, adding 3-7 wt% of polyvinyl alcohol binder, continuously stirring for 0.5 hour, and then granulating in a spray tower;

5) molding and plastic removal: preparing a blank body with the diameter of 25 multiplied by 2.5-2.8 mm from the granulated powder through a dry pressing forming method; keeping the molded blank at the temperature of 750-850 ℃ for 2-5 hours to remove the glue;

6) and (3) sintering: sealing and sintering at 1270-1310 ℃, and keeping the temperature for 2 h;

7) an upper electrode: after the porcelain piece is sintered, the main plane is coated with a silver electrode after grinding, cleaning and drying, then the porcelain piece is placed in a heating furnace, the temperature is raised to 750 ℃, the heat is preserved for 30 minutes, and the porcelain piece is naturally cooled to room temperature;

8) polarization: and (3) polarizing the electrode sample in silicone oil at the temperature of 130-140 ℃ by applying a direct current electric field of 2.0-2.5 kv/mm.

Further, in step 2), mixing: the synthesized LiNb0₃Adding lead tetraoxide, zirconium dioxide, titanium dioxide and antimony trioxide into a roller mill, mixing for 18 hours by a wet method, fully mixing uniformly, and discharging slurry.