High-voltage, high-dielectric, high-curie piezoelectric ceramic sheet

Abstract

This invention discloses a high-voltage, high-dielectric, and high-Curie piezoelectric ceramic chip, belonging to the category of piezoelectric ceramic chips; its composition formula is Pb. 0.99 La y (Zr 0.49 Ti 0.51 ) 0.98‑x (Mg 1 / 2 W 1 / 2 ) 0.02 (Ni 1 / 3Nb 2 / 3 ) x O3, x = 0.12, y = 0.01; its preparation method is to formulate the ingredients according to the stated formula, then ball mill, pre-fire, secondary ball mill, pressing into sheets, debinding and sintering, silver printing, and polarization. The ceramic sheet of this invention has a Tc = 280℃ and d... 33 With a strength of ≥600pC / N, Kp≥0.75, ε≥2500, and tanδ≤1.8%, this invention has the advantages of simple preparation process, low cost, and easy mass production, and is a piezoelectric ceramic material suitable for piezoelectric transducers.

Description

Technical Field

[0001] This invention relates to a piezoelectric ceramic sheet, and more particularly to a high-voltage, high-dielectric, and high-Curie piezoelectric ceramic chip; belonging to the field of piezoelectric ceramic technology. Background Technology

[0002] La doping on PZT ceramics 3+ Partial Pb substitution at the A atom position 2+ This can improve the dielectric, piezoelectric, and ferroelectric properties of PZT ceramics. Due to the high piezoelectric and dielectric constants and large mechanical coupling coefficients of PLZT piezoelectric ceramics, they have extremely broad application prospects in ultrasonic motors, actuators, hydrophones, and various piezoelectric electroacoustic devices.

[0003] With the continuous development of high technology, in order to obtain greater energy conversion efficiency, higher requirements are put forward for the piezoelectric properties of piezoelectric materials, such as piezoelectric strain constant and electromechanical coupling coefficient; therefore, it is urgent to develop a piezoelectric ceramic material with high piezoelectric strain constant, high coupling coefficient, high Curie temperature, and suitable for piezoelectric transducers. Summary of the Invention

[0004] In view of the above-mentioned defects in the prior art, the present invention aims to provide a high-voltage, high-dielectric, and high-Curie piezoelectric ceramic sheet.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: according to the component formula Pb 0.99 La y (Zr 0.49 Ti 0.51 ) 0.98-x (Mg 1 / 2 W 1 / 2 ) 0.02 (Ni 1 / 3 Nb 2 / 3 ) x O3, with a stoichiometric ratio of x = 0.12 and y = 0.01, is prepared by weighing and mixing the raw material oxides Pb3O4, ZrO2, TiO2, NiO, Nb2O5, La2O3, WO3, and MgO; the preparation steps are as follows:

[0006] 1) Mix the above raw material oxides, ball mill and dry to obtain primary abrasive with an average particle size of 2μm;

[0007] 2) Heat the primary abrasive to 850°C, hold for 2 hours, and cool with the furnace to obtain ceramic powder;

[0008] 3) The ceramic powder is ball-milled and dried to obtain secondary abrasive with an average particle size of 0.74 μm;

[0009] 4) PVA with a concentration of 4% is added to the secondary abrasive, mixed, granulated, and pressed into tablets to obtain a green body. The amount of PVA added is 4wt%.

[0010] 5) Heat the green body to 600°C, remove the glue for 1 hour, then raise the temperature to 1220°C and hold for 2 hours, then cool it in the furnace to obtain ceramic slabs;

[0011] 6) The surface of the ceramic tile is printed with silver paste, and then kept at 750℃ for 20 minutes;

[0012] 7) Place the silver-treated ceramic sheet in dimethyl silicone oil at 90℃ for 25 minutes to polarize it, with a polarization electric field strength of 2.5KV / mm.

[0013] Compared with the prior art, the piezoelectric ceramic chip of the present invention has a Tc of 280℃ and a d 33 With a strength of ≥600pC / N, Kp≥0.75, ε≥2500, and tanδ≤1.8%, this invention has the advantages of simple preparation process, low cost, and easy mass production, and is a piezoelectric ceramic material suitable for piezoelectric transducers. Detailed Implementation

[0014] The present invention will be further described below with reference to specific embodiments:

[0015] Example 1

[0016] 1) According to the component formula Pb 0.99 La y (Zr 0.49 Ti 0.51 ) 0.98-x (Mg 1 / 2 W 1 / 2 ) 0.02 (Ni 1 / 3 Nb 2 / 3 ) x O3, x = 0.12, y = 0.01. Weigh out the following raw material oxides: 68.32 mol% Pb3O4, 15.68 mol% ZrO2, 10.57 mol% TiO2, 0.9 mol% NiO, 3.21 mol% Nb2O5, 0.49 mol% La2O3, 0.7 mol% WO3, and 0.12 wt.% MgO.

[0017] 2) Mix the above raw material oxides, ball mill and dry to obtain primary abrasive with an average particle size of 2μm;

[0018] 3) Heat the primary abrasive to 850°C, hold for 2 hours, and cool with the furnace to obtain ceramic powder;

[0019] 4) The ceramic powder is ball-milled and dried to obtain secondary abrasive with an average particle size of 0.74 μm;

[0020] 5) Add 4% PVA to the secondary abrasive, mix, granulate, and press into tablets to obtain a green body. The amount of PVA added is 4 wt%.

[0021] 6) Heat the green body to 600°C, remove the glue for 1 hour, then raise the temperature to 1220°C and hold for 2 hours, then cool it in the furnace to obtain ceramic slabs;

[0022] 7) The surface of the ceramic tile is printed with silver paste, and then kept at 750℃ for 20 minutes;

[0023] 8) Place the silver-treated ceramic sheet in dimethyl silicone oil at 90℃ for 25 minutes to polarize it, with a polarization electric field strength of 2.5KV / mm.

Claims

1. A high-voltage, high-dielectric, high-Curie piezoelectric ceramic sheet, characterized in that... According to the composition formula Pb 0.99 La y (Zr 0.49 Ti 0.51 ) 0.98-x (Mg 1 / 2 W 1 / 2 ) 0.02 (Ni 1 / 3 Nb 2 / 3 ) x O3, with a stoichiometric ratio of x = 0.12 and y = 0.01, the raw material oxides Pb3O4, ZrO2, TiO2, NiO, Nb2O5, La2O3, WO3, and MgO were weighed and mixed. The preparation steps are as follows: 1) Mix the above raw material oxides, ball mill and dry to obtain primary abrasive with an average particle size of 2μm; 2) Heat the primary abrasive to 850°C, hold for 2 hours, and cool with the furnace to obtain ceramic powder; 3) The ceramic powder is ball-milled and dried to obtain secondary abrasive with an average particle size of 0.74 μm; 4) PVA with a concentration of 4% is added to the secondary abrasive, mixed, granulated, and pressed into tablets to obtain a green body. The amount of PVA added is 4wt%. 5) Heat the green body to 600°C, remove the glue for 1 hour, then raise the temperature to 1220°C and hold for 2 hours, then cool it in the furnace to obtain ceramic slabs; 6) The surface of the ceramic tile is printed with silver paste, and then kept at 750℃ for 20 minutes; 7) Place the silver-treated ceramic sheet in dimethyl silicone oil at 90℃ for 25 minutes to polarize it, with a polarization electric field strength of 2.5KV / mm.