KR19990056602A - Piezoelectric ceramic composition - Google Patents

Abstract

In the present invention, xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (0.05≤x≤0.10mol%, 0.4≤y≤0.5mol%, 0.4≤z≤0.5mol %, 0.3≤k≤1.0wt%, 0.05≤l≤0.20wt%), which has a high mechanical quality factor (Qm) and an electromechanical coupling coefficient (Kp). The present invention relates to a piezoelectric magnetic composition that can be widely used, and thus can be widely used in piezoelectric transformers, actuators, ultrasonic vibrators and the like.

Description

Piezoelectric ceramic composition

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to piezoelectric ceramic compositions, and to piezoelectric ceramic compositions having a high mechanical quality factor (Qm) and a high electromechanical coefficient (Kp) that can be used in piezoelectric transformers.

As a conventional piezoelectric ceramic composition, lead zirconate titanate (PZT) is widely known, but it does not completely exhibit various properties satisfying various electronic products. For this reason, the properties are realized by substituting various elements in the A site or B site of lead zirconate titanate (PZT), or the lead magnesium neobate (Pb (Mg _1/3 Nb _2/3 ) O ₃ ) ), Lead Manganese Nebate (Pb (Mn _1/2 Nb _2/3 ) O ₃ ), Lead Zinc Nebate (Pb (Zn _1/3 Nb _2/3 ) O ₃ ), Lead Nickel Nebate (Pb (Ni _A composition with addition of _1/3 Nb _2/3 ) O ₃ ) was used. However, since they have a high sintering temperature in common, there is a difficulty in manufacturing a stacked device, and there is a problem that it is difficult to realize stable characteristics due to volatilization of lead oxide (PbO).

The present invention has been drawn to solve the problems described above, the copper oxide (CuO) in the basic Samsung equation represented by Pb (Sb _2/3 W _1/3 ) O ₃ -PbTiO ₃ -PbZrO ₃ + MnO ₂ It is an object to provide a piezoelectric composition which can be sintered at low temperature by adding a small amount) and having a high mechanical quality factor (Qm) and an electromechanical coupling coefficient (Kp).

The present invention for achieving the above technical problem is xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (0.05≤x≤0.10mol%, 0.4≤y≤0.5mol %, 0.4 ≦ z ≦ 0.5mol%, 0.3 ≦ k ≦ 1.0wt%, 0.05 ≦ l ≦ 0.20wt%).

An embodiment of the present invention will be described as follows.

Lead oxide (PbO), zirconium oxide (ZrO ₂ ), titanium oxide (TiO ₂ ), Sb ₂ O ₃ , WO ₃ , manganese oxide (MnO ₂ ), and copper oxide (CuO) may be the compositions of the following examples. After weighing, wet mixing and drying process, calcining and grinding at 800 ~ 1,000 ℃ for 2 hours. PVA (Poly Vinyl Alcohol) binder was added to the pulverized material, and then formed into disc pellets having a diameter of 24 mm and a thickness of 1.5 mm, followed by sintering at 1000 to 1100 ° C. for 2 hours. The silver (Ag) electrode is formed on both surfaces of the sintered body as described above, and a direct current voltage of 3 to 4 kV mm is applied for 10 to 30 minutes in silicone oil, and then each method is used in the art. The density, electromechanical coupling factor (Kp), mechanical quality factor (Qm) and capacitance of the examples were measured and the results were obtained. As can be seen in the following <Example 1>, <Example 3>, the piezoelectric composition can be applied because it satisfies the characteristics required in the piezoelectric transformer.

<Example 1>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%, l = 0.05wt%) and the piezoelectric ceramic composition was prepared by the above method at the sintering temperature of 1100 ℃, the density was 7.83g / cm ³ , the electromechanical coefficient (Kp) 61%, mechanical quality factor ( Qm) is 1350 and dielectric constant (ε _r ) is 1400.

<Example 2>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%, l = 0.10wt%) of the piezoelectric ceramic of the composition to the sintering temperature at 1100 ℃ as a result of manufacture of the above method, density of 7.69g / cm ^3, 58% electromechanical coupling factor (Kp), mechanical quality factor by composition ( Qm) is 1170 and dielectric constant (ε _r ) is 1630.

<Example 3>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%, l The piezoelectric ceramic composition composed of = 0.10 wt%) was prepared by the above method at the sintering temperature of 1050 ° C., and the density was 7.79 g / cm ³ , the electromechanical coefficient (Kp) was 62%, and the mechanical quality factor ( Qm) was 1460 and dielectric constant (ε _r ) was 1570.

<Example 4>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%, l = 0.20wt%) of the piezoelectric ceramic at the sintering temperature 1050 ℃ the composition to have the result of producing in the above-described way, and the density was 7.88g / cm ^3, 55% electromechanical coupling factor (Kp), mechanical quality factor by composition ( Qm) was 1390 and dielectric constant (ε _r ) was 1600.

Example 5

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%, l The piezoelectric ceramic composition composed of = 0.20 wt%) was prepared by the above method at the sintering temperature of 1000 ° C., and the density was 7.46 g / cm ³ , the electromechanical coefficient (Kp) was 49%, and the mechanical quality factor ( Qm) is 970 and dielectric constant (ε _r ) is 1900.

<Example 6>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.10mol%, y = 0.45mol%, z = 0.45mol%, k = 0.50wt%, l = 0.05 wt%), the piezoelectric ceramic composition was prepared by the above method at the sintering temperature of 1100 ° C., and the density was 7.75 g / cm ³ , the electromechanical coefficient (Kp) was 56%, and the mechanical quality factor ( Qm) was 1330 and dielectric constant (ε _r ) was 1200.

<Example 7>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.10mol%, y = 0.45mol%, z = 0.45mol%, k = 0.50wt%, l = 0.10wt%) of the piezoelectric ceramic results produced at the sintering temperature 1050 ℃ the composition so as to have in the above-described way, and the density was 7.81g / cm ^3, 58% electromechanical coupling factor (Kp), mechanical quality factor by composition ( Qm) is 1300 and dielectric constant (ε _r ) is 1470.

<Example 8>

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.10mol%, y = 0.45mol%, z = 0.45mol%, k = 0.50wt%, l = 0.15wt%) of the piezoelectric ceramic at the sintering temperature 1050 ℃ the composition to have the result of producing in the above-described way, and the density was 7.84g / cm ^3, 57% electromechanical coupling factor (Kp), mechanical quality factor by composition ( Qm) is 1290 and dielectric constant (ε _r ) is 1360.

Example 9

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO (x = 0.10mol%, y = 0.45mol%, z = 0.45mol%, k = 0.50wt%, l The piezoelectric ceramic composition composed of 0.20 wt%) was prepared by the above method at the sintering temperature of 1000.degree. C., the density was 7.53 g / cm ³ , the electromechanical coefficient (Kp) was 43%, and the mechanical quality factor ( Qm) is 1600 and dielectric constant (ε _r ) is 1180.

Example 1

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ (x = 0.05mol%, y = 0.45mol%, z = 0.50mol%, k = 0.50wt%) The piezoelectric ceramic composition was prepared at the sintering temperature of 1100 ° C. by the above method. The density was 7.72g / cm ³ , the electromechanical coefficient (Kp) was 60%, the mechanical quality factor (Qm) was 1270, and the dielectric constant ( ε _r ) exhibited a characteristic of 1240

Example 2

xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ (x = 0.10mol%, y = 0.45mol%, z = 0.45mol%, k = 0.50wt%) The piezoelectric ceramic composition was prepared at the sintering temperature of 1100 ° C. by the above method. The density was 7.70 g / cm ³ , the electromechanical coefficient (Kp) was 51%, the mechanical quality factor (Qm) was 1200, and the dielectric constant ( ε _r ) exhibited a property of 875.

Example mol% wt% Sintering Temperature Density (g / cm ³ ) Electromechanical Coupling Factor Kp (% 60) Mechanical Quality Factor Q _m ε _r x y z k l One 0.05 0.45 0.50 0.50 0.05 1100 7.83 61 1350 1400 2 0.05 0.45 0.50 0.50 0.0 1100 7.69 58 1170 1630 3 0.05 0.45 0.50 0.50 0.10 1050 7.79 62 1460 1570 4 0.05 0.45 0.50 0.50 0.20 1050 7.88 55 1390 1600 5 0.05 0.45 0.50 0.50 0.20 1000 7.46 49 970 1900 6 0.10 0.45 0.45 0.50 0.05 1100 7.75 56 1330 1200 7 0.10 0.45 0.45 0.50 0.10 1050 7.81 58 100 1470 8 0.10 0.45 0.45 0.50 0.15 1050 7.84 57 1290 1360 9 0.10 0.45 0.45 0.50 0.20 1000 7.53 43 1600 1180 Comparative Example 1 0.05 0.45 0.50 0.50 1100 7.72 60 1270 1240 Comparative Example 2 0.10 0.45 0.45 0.50 1100 7.51 51 1200 875

_{* Comparative example is other than the main experiment.}

The piezoelectric composition according to the present invention has a high electromechanical coupling factor (Kp) and a mechanical quality factor (Qm), and can be sintered at low temperatures, thereby enabling applications of piezoelectric transformers, actuators, and ultrasonic vibrators. Do.

Claims (2)

A piezoelectric ceramic composition, wherein the composition component and the ratio are represented by the following formula. xPb (Sb _2/3 W _1/3 ) O ₃ -yPbTiO ₃ -zPbZrO ₃ + kMnO ₂ + lCuO In the above, 0.05≤x≤0.10mol%, 0.4≤y≤0.5mol%, 0.4≤z≤0.5mol%, 0.3≤k≤1.0wt%, 0.05≤l≤0.20wt%. The method of claim 1, A piezoelectric ceramic composition, wherein k is 0.5wt%.