KR20060089344A - A method for manufacturing low temperature sintering ceramics - Google Patents

Abstract

Pb [(Co _1/2 W _1/2 ) _0.02 (Mn _1/3 Nb _2/3 ) _0.07 (Zr _0.48 Ti _0.52 ) _0.91 ] O ₃ +0.3 wt% CuO + 0.3 wt% Bi ₂ O ₃ + The present invention relates to a method for producing PCW-PMN-PZT ceramics having a basic formula of Xwt% Li ₂ CO ₃ . This method is a step of weighing the sample according to the composition formula to a predetermined unit by acetone as a dispersion medium by mixing, pulverizing for a predetermined time using a zirconia ball of a predetermined size, dried, put into an alumina crucible and calcining for a predetermined time at a predetermined temperature ( s10), after the calcination, a predetermined additive is added, remixed for a predetermined time, pulverized and dried, a predetermined amount of a predetermined aqueous solution is added, and a molding is performed at a predetermined pressure using a molder having a predetermined diameter (s20). Burning the binder contained in the molded ceramics at a predetermined temperature for a predetermined time (s30) and sintering at a predetermined temperature for a predetermined time when the temperature changes at a predetermined speed after burning the binder (s40). It is done by

PCW-PMN-PZT ceramics, additives, sintered, grain, X-ray diffraction, dielectric constant, piezoelectric constant.

Description

A method for manufacturing low temperature sintering ceramics}             

Figure 1a shows the microstructure of the specimen according to the change in the amount of Li ₂ CO ₃ addition at 920 ℃ firing.

Figure 1b shows the microstructure of the specimen according to the change of the additive during the firing at 1200 ℃.

2 shows the grain size with Li ₂ CO ₃ addition.

3 shows the density with Li ₂ CO ₃ addition.

4 shows the X-ray diffraction pattern according to the addition of Li ₂ CO ₃ .

Figure 5 shows the electromechanical coupling coefficient with Li ₂ CO ₃ addition.

6 shows the mechanical quality factor according to the addition of Li ₂ CO ₃ .

Figure 7 shows the dielectric constant with Li ₂ CO ₃ addition.

8 shows the temperature dependence of the dielectric constant according to the addition of Li ₂ CO ₃ .

9 shows piezoelectric constants according to the addition of Li ₂ CO ₃ .

10 is a flowchart of an embodiment of a low-temperature sintered PCW-PMN-PZT ceramic manufacturing method using a sintering aid according to the present invention.

The present invention relates to a method for producing low temperature sintered PCW-PMN-PZT ceramics using sintering aids.

In general, PZT-based piezoceramics are widely used in various applications such as piezoelectric transformers, actuators, ultrasonic motors, filters, and resonators due to their excellent piezoelectric and dielectric properties. However, PZT-based piezoceramics have a firing temperature of more than 1200 ° C, causing problems of degradation of piezoelectric properties due to PbO showing rapid volatilization at 1000 ° C, energy loss, and environmental pollution. The manufacturing cost increases due to the increase in the Pd content of the Ag / Pd electrode used as an internal electrode in Therefore, in order to use PZT series piezoelectric ceramics exhibiting high-performance piezoelectric properties, a piezoceramic composition that can be sintered at a low temperature of 1000 ° C. or lower is required. In particular, in order to use only pure Ag electrodes in a laminated structure, a temperature of 950 ° C. or lower can be used. There is a need to develop piezoelectric ceramics that are calcinable and have excellent piezoelectric properties. Research on low temperature firing has been done through various kinds of methods such as adding liquid-forming additives, using very fine powder as an initial sample, and hot pressing. In particular, liquid phase sintering is known to be the most effective method of reducing the firing temperature. This method promotes density by lubrication at the grain boundary due to liquid phase at a temperature lower than that of PZT-based ceramics, which generally have a firing temperature of 1200 ° C, because the liquid phase is formed at the beginning of firing. This is how you do it.

In order to solve the problems of the prior art described above, in order to induce low-temperature firing and improve piezoelectric and dielectric properties, such as CuO, the addition amount of CuO as a sintering accelerator in PCW-PMN-PZT ceramics is 0.3. It is an object to provide a low-temperature sintered PCW-PMN-PZT ceramics production method using a sintering aid by fixing to wt%, by adding Bi2O3 and Li2CO3.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention and the accompanying drawings.

Configuration of Preferred Embodiment

The method for preparing PCW-PMN-PZT ceramics according to the present invention has the basic formula shown in Chemical Formula 1, and a preferred embodiment of this method is a zirconia having a predetermined size as a dispersion medium by basing the sample according to the above formula to a predetermined unit. After mixing, pulverizing and drying for a predetermined time using a ball, and putting in an alumina crucible and calcining at a predetermined temperature for a predetermined time (S10), after the calcination, a predetermined additive is added, remixed for a predetermined time, pulverized and dried , Adding a predetermined amount of a predetermined aqueous solution, and molding at a predetermined pressure using a molder having a predetermined diameter (S20), burning the binder included in the molded ceramics at a predetermined temperature for a predetermined time (S30) and the Sintering for a predetermined time at a predetermined temperature when the temperature is changed at a predetermined rate after burning the binder (S40) All.

Pb [(Co _1/2 W _1/2 ) _0.02 (Mn _1/3 Nb _2/3 ) _0.07 (Zr _0.48 Ti _0.52 ) _0.91 ] O ₃ + 0.3wt% CuO + 0.3wt% Bi ₂ O ₃ + Xwt% Li ₂ CO ₃

X value was changed from 0 to 0.5 wt% and CuO, Bi ₂ O ₃ and Li ₂ CO ₃ were added after calcination.

<How it works>

Hereinafter, the operation principle of a preferred embodiment of the low-temperature sintered PCW-PMN-PZT ceramic manufacturing method using the sintering aid according to the present invention will be described in detail. In particular, the ceramic specimens are prepared through this method, and the characteristics of the specimens prepared to confirm the performance of the ceramics manufacturing method according to the present invention will be described.

1. Ceramic Specimen Manufacturing

The basic formula used in the present invention is the same as in Formula 1 to prepare a specimen by the oxide mixing method. The sample according to the composition was weighed to 10 ^-4 g, mixed with acetone using a 3mm zirconia ball as a dispersion medium for 24 hours, pulverized and dried, and then placed in an alumina crucible and calcined at 850 ° C. for 2 hours. After calcination, the additive was added, remixed for 24 hours, pulverized and dried, and 8% of PVA (5% aqueous solution) was added thereto, and then molded to 1 ton / cm ² using a 21 mmφ molder. The molded specimen was burned at 600 ° C. for 3 hours, and then sintered at a temperature of 830 ° C. to 980 ° C. at a temperature of 3 ° C./min. In order to measure the electrical properties of the specimen, the Ag electrode was applied to the specimen polished to a thickness of 1 mm, heat treated at 650 ° C for 10 minutes, and polarized by applying a 30 kV / cm DC field for 30 minutes in an insulating oil at 120 ° C. The specimen was prepared by treatment. And after 24 hours, the characteristics of the prepared specimens were measured.

2. Measurement of Specimen Properties

In order to verify the properties of the ceramic specimens made according to the present invention to achieve the above object, the piezoelectric and dielectric properties of the sintering aid were measured at firing temperatures of 830 ° C. to 980 ° C. to investigate the low temperature sintering properties.

Dielectric constants were calculated by measuring capacitance at 1 kHz with LCR meter (ANDO AG-4304) according to temperature change in order to investigate the dielectric properties and phase transition temperature at room temperature. (Hitachi, S-2400) and XRD (Rigaku, D / MAX-2500H). In addition, the electromechanical coupling coefficient (k _p ) and mechanical quality coefficient (Q _m ) were calculated by measuring the resonance and anti-resonant frequencies and the resonance resistance with the Impedance Analyzer (Agilent 4294A) according to the IRE standard. D ₃₃ meter (APC 8000) Piezoelectric constant (d ₃₃ ) was measured using.

3. Experiment

Figure 1a shows the microstructure of the specimen with the change of Li ₂ CO ₃ addition amount at 920 ℃ firing, Figure 1b shows the microstructure of the specimen with the change of additives at 1200 ℃ firing. Top left figure Li ₂ CO ₃ added amount is 0.1wt% Li ₂ CO _3, upper right figure shows the case of 0.2wt% Li ₂ CO _3, the bottom left illustration of Figure 1a in Fig. 1a, the Li ₂ CO ₃ added amount 0.3wt% Li ₂ CO ₃ , bottom right picture shows 0.5wt% Li ₂ CO ₃ . In addition, the upper left figure of FIG. 1B shows PCW-PMN-PZT, the right figure shows 0.3 wt% CuO, the lower left figure shows 0.3 wt% Bi ₂ O ₃ , and the right figure shows 0.2 wt% Li ₂ CO ₃ .

As can be seen in FIG. 1, the grain size gradually increased with the addition of Li ₂ CO ₃ , and the maximum value was increased from 0.3 wt% to 2.69 μm, and gradually decreased when added. It can be seen that the grain of the specimen fired by adding the additive at 920 ° C. is larger than the grain size of the PCW-PMN-PZT ceramics fired at ° C.

Figure 2 shows the grain size according to the grain growth and the additive change with the addition of Li ₂ CO ₃ , Table 1 shows a comparison of the grain size according to the additive change.

Figure 3 shows the change in density according to the firing temperature and Li ₂ CO ₃ addition amount. As Li ₂ CO ₃ was increased, the density showed a maximum value at a lower temperature, and firing was possible at a lower temperature than that of 0.3 wt% CuO and 0.3 wt% Bi ₂ O _3. It can be seen that the addition can be fired even at a significantly low temperature of 830 ° C. The maximum density of the specimens was found in the specimens added with 0.2 wt% Li ₂ CO ₃ at 950 ° C and had a size of 7.90 g / cm ³ . In addition, the density according to the amount of each addition showed a characteristic that gradually decreases above the firing temperature showing the maximum value. Measuring a result of this microstructure and the density was seen as a characteristic of forming a liquid phase at around 690 ℃ when is a Bi ₂ O ₃ low-melting oxides (825 ℃) substituting the Li ₂ O of about 10 mol% reacted with Li ₂ O At this time, Li ₂ CO ₃ and Bi ₂ O ₃ used as an additive reacted with each other to form a liquid phase, and further promoted density growth and grain growth at low temperature together with liquid phase sintering of Cu ₂ O-PbO. In addition, the decrease in density and grain size after the maximum value of each addition amount decreased due to the volatility of the liquid phase, and thus the porosity increased.

Figure 4 shows the X-ray diffraction analysis of the specimen prepared by the addition of Li ₂ CO ₃ at 920 ℃. As can be seen from the figure, all specimens produced (002) and (200) peaks showed the tetragonal phase characteristics and the tetragonality (c / a) showed almost the same value regardless of the amount of Li ₂ CO ₃ added. No phase change occurred. In addition, since the secondary phase does not appear, it is considered that CuO, Bi ₂ O ₃ and Li ₂ CO ₃ added as additives are completely dissolved.

Figure 5 shows the change in the electromechanical coupling coefficient (k _p ) with Li ₂ CO ₃ addition. Specimens containing 0.3 wt% or more of Li ₂ CO ₃ could not be polarized due to an increase in porosity due to overfiring when fired at a temperature above 890 ° C. The electromechanical coefficient increased with the addition of Li ₂ CO ₃ at the firing temperature above 920 ℃, and the maximum value was 0.57 at 950 ℃ when 0.2 wt% was added. The electromechanical coefficient of specimens produced at the firing temperature below 920 ℃ decreased with increasing amount, and the electromechanical coefficient increased with increasing sinterability at low temperatures. When 0.4 wt% was added, the maximum value was 0.52 at 860 ° C. In addition, the electromechanical coefficient of the specimens added with CuO and Bi ₂ O ₃ was lower than that of CuO alone. As can be seen from Figure 3, at a temperature above 920 ℃ coincides with the increase of the density according to the amount of addition at each firing temperature by the addition of Li ₂ CO ₃ , and opposite to the change of density at the firing temperature below 920 ℃ The reason for this is that the polarization efficiency was reduced by acting as an impurity by the production of unreacted material by the excessive addition of Li ₂ CO ₃ . In addition, the specimen to which only Bi ₂ O ₃ is added is because Bi ₂ O ₃ does not react and acts as an impurity to reduce the electromechanical coupling coefficient.

6 shows the change in the mechanical quality factor (Q _m ) according to the addition of Li ₂ CO ₃ . As the amount of Li ₂ CO ₃ was increased, the mechanical quality factor showed a decreasing characteristic regardless of the firing temperature. However, the specimens added with 0.2 wt% Li ₂ CO ₃ had higher mechanical quality factor at 920 ℃ due to the increased sinterability than the other specimens. These results show that the electromechanical coupling coefficients shown in FIG. 5 show the opposite trend, and Li ₂ CO ₃ reacts with Bi ₂ O ₃ , which remained as an unreacted substance, to form a liquid phase and an ion radius of 0.96 Å. Bi ³⁺ ions were substituted as Pb ²⁺ with an ion radius of 1.18 작용 to act as a donor to induce Pb ^pores , increasing the electromechanical coefficient and decreasing the mechanical quality coefficient. Because.

Figure 7 shows the change in dielectric constant with the addition of Li ₂ CO ₃ . The change in dielectric constant also shows the same trend as the change in electromechanical coupling coefficient, and as shown in FIGS. 2 and 3, the density increases and grain grows due to the liquid phase generated by the reaction of Li ₂ CO ₃ and Bi ₂ O ₃ . This is because the grain boundary, which is a low dielectric constant layer, is reduced, and the reason why the dielectric constant has a maximum value at a specific firing temperature depending on the amount of additives is that it has an optimum firing density depending on the proportion of the additive forming the liquid phase.

8 shows the temperature dependence of the dielectric constant according to the addition of Li ₂ CO ₃ . Dielectric constant with the addition amount increased at 920 ℃ in proportion to the size of dielectric constant at room temperature, and Curie temperature decreased with the addition amount of Li ₂ CO ₃ , and 347 ℃ when 0.2wt% was added. Curie temperature of These results indicate that the Curie temperature decreases when substitution or vacancy occurs at the A position in ABO ₃ , a perovskite structure, and the addition of Li ₂ CO ₃ reacts with Bi ₂ O _3. This is because some ions are replaced with Pb ions at the A position while forming a liquid phase.

9 shows the change in piezoelectric constant with Li ₂ CO ₃ addition. The change of piezoelectric constant measured according to the amount of Li ₂ CO ₃ addition was consistent with the change of electromechanical coefficient, and 0.3 wt% CuO, Bi ₂ O ₃ , 0.2 wt% Li ₂ at sintering temperature of 950 ℃. The highest value was 376pC / N in the sample added with CO ₃ . This result shows the same change in electromechanical coefficient and dielectric constant as the amount of Li ₂ CO ₃ added, compared with the tendency that the piezoelectric constant has a magnitude proportional to the complex action of the electromechanical coefficient and dielectric constant. Matches the results shown.

Figure 10 shows a flow chart of an embodiment of a low-temperature sintered PCW-PMN-PZT ceramic manufacturing method using a sintering aid according to the present invention.

As a result, the addition of Li ₂ CO ₃ and Bi ₂ O ₃ in PZT-based ceramics forms a liquid phase at 690 ° C. to promote density at low temperatures, while at the same time the Bi ³⁺ (0.96 96) ion has a perovskite structure. In PZT-based ceramics, Pb ²⁺ (1.18 Å) ions in the A position were substituted and acted as donors, showing low-temperature firing and softer effects. As can be seen from these results, the composition developed according to the present invention can be fired at a temperature of 950 ° C. or less, and has excellent piezoelectric properties, and is subsequently applied to the multilayer piezoelectric transformer to use pure Ag electrode as the internal electrode of the multilayer piezoelectric transformer. Applicable to

In Tables 2 and 3, the physical properties of the specimens prepared according to the addition of Li ₂ CO ₃ at each firing temperature are compared with those of the specimens prepared according to the change of additives at 920 ° C. Table 2 shows the optimum characteristics of liquid phase sintering at specific ratios by the combined action of CuO, Bi ₂ O ₃ , and Li ₂ CO ₃ at each firing temperature. It can be seen that the piezoelectric and dielectric properties increase due to the increase in sinterability and the substitution effect. Table 2 shows the physical properties of the specimen according to the addition of Li ₂ CO ₃ , Table 3 shows the physical properties of the specimen according to the additive change.

As such, the present invention may be variously modified and may take various forms, and only the specific embodiments thereof are described in the detailed description of the present invention. It is to be understood, however, that the present invention is not limited to the specific forms mentioned in the detailed description of the invention, but rather includes all modifications, equivalents, and substitutions within the spirit and scope of the invention as defined by the appended claims. It should be understood to do.

In the present invention, in order to develop low-temperature sintered ceramics for multilayer piezoelectric transformer, the X value is changed from 0 to 0.5 wt% in the composition of Chemical Formula 1 and the firing temperature of 830 ° C to 980 ° C is changed according to the manufacturing method of the present invention. The ceramic specimens were fabricated and confirmed to have the following effects.

1. All specimens prepared by Li ₂ CO ₃ addition showed tetragonal crystal structure, tetragonality showed almost the same size, and secondary phase did not appear.

2. As the amount of Li ₂ CO ₃ is increased, the density of the specimen shows the maximum value at the low temperature side by reaction with Bi ₂ O ₃ , and the grain grows due to the increase of sinterability.

_{3. The} addition of Li ₂ CO ₃ increases the electromechanical coupling coefficient (k _p ) and dielectric constant, and the mechanical quality coefficient (Q _m ) and Curie temperature decrease, and the piezoelectric constant changes with electromechanical coupling coefficient. Matches

4. The addition of Li ₂ CO ₃ forms a liquid phase by reaction with Bi ₂ O ₃ , which acts as a donor at the same time as a low temperature firing in PZT-based ceramics, and shows a softner effect.

5. The composite addition of 0.3 wt% CuO, Bi ₂ O ₃ and 0.2 wt% Li ₂ CO _{3 to} PCW-PMN-PZT ceramics was k _p = 0.56, Q _m = 1000, ε _r = at sintering temperature of 920 ° C. 1457, d ₃₃ = 350pC / N, T _c = 347 ℃ and can be applied to multilayer piezoelectric transformer.

Claims (19)

Pb [(Co _1/2 W _1/2 ) _0.02 (Mn _1/3 Nb _2/3 ) _0.07 (Zr _0.48 Ti _0.52 ) _0.91 ] O ₃ + 0.3wt% CuO + 0.3wt% Bi ₂ O ₃ + Xwt% Li ₂ CO ₃ In the manufacturing method of PCW-PMN-PZT ceramics having the basic composition of Weighing the sample according to the composition formula to a predetermined unit, mixing and pulverizing with acetone using a zirconia ball of a predetermined size as a dispersion medium for a predetermined time, drying and placing the same in an alumina crucible and calcining at a predetermined temperature for a predetermined time; Adding a predetermined additive after the calcination, remixing for a predetermined time, pulverizing and drying, adding a predetermined amount of a predetermined aqueous solution, and molding at a predetermined pressure using a molder having a predetermined diameter; Burning the binder contained in the molded ceramics at a predetermined temperature for a predetermined time; And And burning the binder and sintering at a predetermined temperature for a predetermined time when the temperature changes at a predetermined rate. The method for manufacturing low-temperature sintered PCW-PMN-PZT ceramics using a sintering aid. According to claim 1, wherein the size of the zirconia ball is 3mm, the predetermined mixing and grinding time is 24 hours, the change range of the X value is 0 ~ 0.5 wt%, the predetermined basis weight unit is 10 ^-4 g The calcination temperature is 850 ℃, the calcination time is 2 hours, characterized in that the low-temperature sintering PCW-PMN-PZT ceramic production method using a sintering aid. The method of claim 1, wherein the predetermined time for remixing and grinding in the forming step is 24 hours, the predetermined additive is CuO, Bi ₂ O ₃ and Li ₂ CO ₃ , the predetermined amount of the aqueous solution is PVA (5% Aqueous solution) 8%, the mold diameter is 21 mmφ, the molding pressure is 1 ton / cm ² , low temperature sintering PCW-PMN-PZT ceramic production method using a sintering aid. The method of claim 1, wherein the predetermined temperature and time to burn the binder is 600 ℃ and 3 hours, respectively, characterized in that the low-temperature sintering PCW-PMN-PZT ceramics manufacturing method using a sintering aid. The method of claim 1, wherein the predetermined temperature change rate in the sintering step is 3 ℃ / min, wherein the predetermined temperature is characterized in that 830 ~ 980 ℃, low temperature sintering PCW-PMN-PZT ceramics production using Way. The method of claim 3, wherein the grain size gradually increases as the amount of the additive Li ₂ CO ₃ is increased, and the maximum value is increased from 0.3 wt% to 2.69 μm, and gradually decreases when the additive is added. A method for producing low-temperature sintered PCW-PMN-PZT ceramics using a sintering aid, characterized in that the grains of the specimens fired by adding an additive at 920 ° C. are larger than the grain size of the fired PCW-PMN-PZT ceramics. 4. The method of claim 3, wherein the density of the Li ₂ CO ₃ increases as the addition amount increases at a lower temperature, and calcined at a lower temperature than when only 0.3 wt% CuO and 0.3 wt% Bi ₂ O ₃ are added. When 0.5 wt% is added, firing is possible at 830 ° C, and the maximum density of the ceramics produced by the above method is 7.90 g / g when 0.2 wt% Li ₂ CO ₃ is added at 950 ° C. have a size of cm ^3, the density for each addition amount is gradually decreased at the firing temperature or higher exhibit a maximum value, a low-melting-point oxide, Bi ₂ O ₃ reacts with Li ₂ O substitution of Li ₂ O of about 10 mol% Low temperature sintered PCW-PMN-PZT ceramics manufacturing method using a sintering aid, characterized in that the liquid form in the vicinity of 690 ℃. The method of claim 3, wherein the ceramics produced regardless of the amount of Li ₂ CO ₃ added (002), (200) peak and exhibit a tetragonal phase characteristics, tetragonal (c / a) is almost the same value The low temperature sintered PCW-PMN-PZT ceramic production method using a sintering aid, characterized in that the phase change does not occur, the secondary phase does not appear. The method of claim 3, wherein the ceramics added with 0.3 wt% or more of Li ₂ CO ₃ cannot be polarized due to an increase in porosity due to overfiring when fired at a temperature of 890 ° C. or higher, and Li ₂ CO at a firing temperature of 920 ° C. or higher. _The electromechanical coupling coefficient increased with the addition of ₃ , and the maximum value of 0.57 wt% at 950 ℃ increased to 0.57, and the electromechanical coupling coefficient of ceramics produced at the firing temperature below 920 ℃ decreased with the increase of the added amount. The electromechanical coefficient increased due to the increase of sinterability at low temperatures, and the maximum value was 0.52 at 860 ° C when 0.4 wt% was added, and the complex of CuO and Bi ₂ O ₃ was added. A method for producing low-temperature sintered PCW-PMN-PZT ceramics using a sintering aid, characterized in that the electromechanical coefficient is reduced compared to the specimens containing only CuO. The method according to claim 3, wherein as the amount of Li ₂ CO ₃ is increased, the mechanical quality coefficient decreases regardless of the firing temperature, and when 0.2 wt% Li ₂ CO ₃ is added, Low temperature sintered PCW-PMN-PZT ceramics manufacturing method using a sintering aid, characterized in that the mechanical quality factor due to the increase. The sintering aid according to claim 3, characterized in that the dielectric constant has a maximum value at a specific firing temperature according to the addition amount of each additive because it has an optimum firing density according to the ratio of the additive forming the liquid phase. Low temperature sintered PCW-PMN-PZT ceramic manufacturing method. The dielectric constant according to the change in the amount of the additive added at 920 ° C. increases in proportion to the size of the dielectric constant at room temperature, and the Curie temperature decreases according to the amount of Li ₂ CO ₃ added. A low temperature sintered PCW-PMN-PZT ceramic production method using a sintering aid, characterized by a Curie temperature of 347 ° C. at the time of addition. The change in piezoelectric constant measured according to the amount of Li ₂ CO ₃ added is consistent with the change in the electromechanical coupling coefficient, and 0.3 wt% CuO and Bi ₂ O ₃ , 0.2 wt% at the sintering temperature of 950 ° C. A low-temperature sintered PCW-PMN-PZT ceramics manufacturing method using a sintering aid, characterized in that the largest value of 376pC / N in the ceramics to which Li ₂ CO ₃ is added. The low temperature sintered PCW-PMN-PZT ceramic manufacturing method using a sintering aid according to claim 1, characterized in that a composition which is calcinable at a temperature of 980 ° C. or lower is used to use only pure Ag electrodes in a laminated structure. The addition of Li ₂ CO ₃ and Bi ₂ O ₃ in PZT-based ceramics forms a liquid phase at 690 ° C. to promote densification at low temperatures, while at the same time the Bi ³⁺ (0.96 Å) ion PZT-based ceramics are substituted with Pb ²⁺ (1.18 kW) ions in the A position and act as donors to exhibit low temperature sintering and softner effect, and the ceramics of the composition are used as internal electrodes of multilayer piezoelectric transformers. A low-temperature sintered PCW-PMN-PZT ceramics manufacturing method using a sintering aid, which is calcinable at a temperature of 950 ° C. or lower so as to use only pure Ag electrodes. 4. The low temperature sintered PCW-PMN using the sintering aid according to claim 3, wherein the ceramics produced by the addition of Li ₂ CO ₃ exhibit a tetragonal crystal structure, tetragonality almost the same size, and secondary phases do not appear. -PZT ceramic manufacturing method. The method of claim 3, wherein the density of the ceramics produced by the method by the reaction with Bi ₂ O ₃ as the amount of Li ₂ CO ₃ addition increases the maximum value at the low temperature side, grain is characterized by the growth of sinterability , Low temperature sintered PCW-PMN-PZT ceramic production method using sintering aid. The method of claim 3, wherein the addition of Li ₂ CO ₃ forms a liquid phase by reaction with Bi ₂ O ₃ to act as a donor at the same time as a low-temperature firing in PZT-based ceramics, showing a softner effect, using a sintering aid Low temperature sintered PCW-PMN-PZT ceramic manufacturing method. The composite addition of 0.3 wt% CuO, Bi ₂ O ₃ and 0.2 wt% Li ₂ CO _{3 to} the PCW-PMN-PZT ceramics is characterized by k _p = 0.56, Q _m = 1000 at a sintering temperature of 920 ° C. , ε _r = 1457, d ₃₃ = 350pC / N, T _c = 347 ℃ value, characterized in that the application as a laminated piezoelectric transformer, low temperature sintering PCW-PMN-PZT ceramic production method using a sintering aid.

Images