JP2004244300A - Piezoelectric ceramic composition, its production method, piezoelectric element, and dielectric element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric ceramic composition which is lead-free and has a high apparent density, a low porosity, and a low open porosity, to provide its production method, and to provide a piezoelectric element and a dielectric element using the piezoelectric ceramic composition. <P>SOLUTION: The piezoelectric ceramic composition mainly consists of a compound represented by the formula: äLi<SB>x</SB>(K<SB>1-y</SB>Na<SB>y</SB>)<SB>1-x</SB>}(Nb<SB>1-z-w</SB>Ta<SB>z</SB>Sb<SB>w</SB>)O<SB>3</SB>(wherein x, y, z, and w are in the ranges: 0≤x≤0.2, 0≤y≤1, 0<z≤0.4, and 0<w≤0.2, respectively). This composition contains as an additive element at least one metallic element selected from specified elements. The total content of the additive is 0.0005 to 0.15 mol per mol of the compound represented by the formula. The open porosity is at most 0.4 vol.%. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a piezoelectric ceramic composition containing no lead in the composition, a method for producing the same, and a piezoelectric element and a dielectric element using the piezoelectric ceramic composition as a material.

Conventionally, a PZT (PbTiO ₃ -PbZrO ₃ ) component-based ceramic containing lead has been used as a piezoelectric ceramic composition. This is because PZT exhibits large piezoelectricity and has a high mechanical quality factor, and can easily produce materials having various characteristics required for each application such as a sensor, an actuator, and a filter.
Further, since the PZT has a high relative dielectric constant, it can be used as a capacitor or the like.

However, while the piezoelectric ceramic composition comprising PZT has excellent properties, it contains lead as a constituent element, so that harmful lead is eluted from industrial waste of products containing PZT, resulting in environmental pollution. Could be caused. And, increasing awareness of environmental issues in recent years has made it difficult to manufacture products that can cause environmental pollution, such as PZT. Therefore, development of a piezoelectric ceramic composition containing no lead in the composition has been demanded, and a piezoelectric ceramic composition represented by the general formula (K _1-x Na _x ) NbO ₃ (where 0 <x <1) (See Non-Patent Document 1).

However, the piezoelectric ceramic composition represented by the above general formula (K _1-x Na _x ) NbO ₃ (where 0 <x <1) has a problem that it is difficult to sinter. Therefore, the piezoelectric ceramic composition after firing has a low apparent density and is likely to form a large number of pores on its surface and inside. Therefore, the conventional piezoelectric ceramic composition represented by the general formula (K _1-x Na _x ) NbO ₃ has a problem that its mechanical strength is apt to decrease.
"Journal of the American Ceramic Society", USA, 1962, Vol. 45, no. 5, p. 209

  The present invention has been made in view of the above-mentioned conventional problems, and is directed to a piezoelectric ceramic composition containing no lead, having a high apparent density, low porosity and low open porosity, a method for producing the same, and the piezoelectric ceramic. An object of the present invention is to provide a piezoelectric element and a dielectric element using the composition.

The first invention of the general formula represented by _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w, respectively 0 A piezoelectric ceramic composition mainly comprising a compound having a composition range of ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4, and 0 <w ≦ 0.2,
The piezoelectric ceramic composition comprises Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir. , La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr One or more metal elements selected from the group consisting of
The total content of the additional elements is 0.0005 mol to 0.15 mol with respect to 1 mol of the compound represented by the general formula.
The piezoelectric ceramic composition has an open porosity of 0.4% by volume or less (claim 1).

Next, the operation and effect of the present invention will be described.
The piezoelectric ceramic composition of the present invention does not contain lead in the composition.
Therefore, the piezoelectric ceramic composition is safe because harmful lead does not leak from the waste and the like to nature.

Further, the piezoelectric ceramic composition contains a compound represented by the above general formula, and contains the additive element within the above range.
Therefore, when the piezoelectric ceramic composition is fired at the time of its production, the above-mentioned additional element acts as a firing aid to promote densification and facilitate sintering. Therefore, a high quality piezoelectric ceramic composition having a high apparent density and a small number of pores is obtained. As a result, the porosity and open porosity are low, and the mechanical properties are excellent. The porosity indicates the amount of porosity formed inside and on the back surface of the piezoelectric ceramic composition by volume%, and the open porosity indicates the amount of dents formed on the surface of the piezoelectric ceramic composition. The amounts are given in volume%.

  Further, the piezoelectric ceramic composition of the present invention has a low open porosity of 0.4 Vol% or less. Therefore, the piezoelectric ceramic composition has excellent mechanical strength and is hardly deteriorated and has high reliability. The piezoelectric actuator element, the piezoelectric vibrator, the surface wave filter element, the piezoelectric sensor element, the ultrasonic motor element, the piezoelectric transformer element, and the like. It can be used as an element.

The piezoelectric ceramic composition of the present invention, as a main component the above general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) represented by O ₃ compound Contains. Therefore, the piezoelectric ceramic composition has excellent piezoelectric d ₃₁ constant, electromechanical coupling coefficient Kp, piezoelectric g ₃₁ constant, mechanical quality factor Qm, relative permittivity, and dielectric loss, which the compound represented by the above general formula has. By utilizing the piezoelectric and dielectric properties such as the Curie temperature and the like, these properties are excellent. Therefore, it can be used as a high-performance piezoelectric element and dielectric element.
Note that does not contain the additive element, a composition represented by the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, less Where appropriate, referred to as the "basic composition".

The second invention of the general formula represented by _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w, respectively 0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4, 0 <w ≦ 0.2, a compound having a composition range of Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn and Zr are mixed with an additive containing at least one metal element and fired. A method for producing a piezoelectric porcelain composition, characterized in that it is characterized by the following (claim 4).

A mixture obtained by mixing the compound represented by the general formula and the additive can be sintered under normal pressure. Therefore, sintering can be performed easily and at low cost.
In particular, in the present invention, an additive containing the above metal element is added to the compound represented by the above general formula. Therefore, the additive functions as a firing aid, and the piezoelectric ceramic composition is easily sintered during the firing. As a result, the apparent density of the piezoelectric ceramic composition after firing can be improved, and large pores are less likely to be generated on the surface and inside thereof, so that the porosity and the open porosity can be reduced. Therefore, the mechanical strength of the piezoelectric ceramic composition after sintering can be improved.

  In addition, in the piezoelectric ceramic composition obtained after the firing, as a result of the addition of the additive, at least one of Li, K, Na, Nb, Ta, and Sb of the compound represented by the general formula is added. At least a portion of Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir , La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr And any one or more metal elements selected from the group consisting of a metal element or a compound containing the metal element or an oxide or a perovskite structure compound in the piezoelectric ceramic composition. It is contained in. In this specification, “containing an additive” has the same meaning as described above.

The piezoelectric ceramic composition obtained after the calcination does not contain lead, the piezoelectric d ₃₁ constant, electromechanical coupling factor Kp, piezoelectric g ₃₁ constant, the mechanical quality factor Qm, dielectric constant, dielectric loss, and Curie It has excellent piezoelectric and dielectric properties such as temperature. Therefore, it can be used as a material for a high-performance piezoelectric element or dielectric element.

According to a third aspect of the present invention, a compound containing Li, a compound containing Na, a compound containing K, a compound containing Nb, a compound containing Ta, and a compound containing Sb are fired. after represented by the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w respectively 0 ≦ x ≦ 0. 2,0 ≦ y ≦ 1,0 <z ≦ 0.4,0 <w ≦ 0.2 at a stoichiometric ratio which results in a compound in the composition range, or a metal contained in the following additives Mixing at stoichiometric ratios taking into account substitution by elements, and furthermore Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, A piezoelectric element characterized in that an additive containing at least one metal element selected from the group consisting of i, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, and Zr is mixed and fired. A method for producing a porcelain composition is provided (claim 5).

In the third invention, as described above, a compound containing Li, a compound containing Na, a compound containing K, a compound containing Nb, a compound containing Ta, and a compound containing Sb are contained. And Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La , Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr And an additive containing at least one metal element are mixed at the above stoichiometric ratio and fired.
Thereby, the piezoelectric ceramic composition of the first invention can be easily obtained.

  Further, in the piezoelectric ceramic composition obtained after the firing, as a result of the addition of the additives, the compounds represented by the general formulas Li, K, Na, Nb, At least a portion of any one or more of Ta and Sb is converted to Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, The piezoelectric ceramic composition contains one or more metal elements selected from V, Y, Yb, Zn, and Zr in a substituted manner, or as a compound such as the metal element or an oxide or a perovskite structure compound containing the metal element. Intragranular or in grain boundaries It is.

  At this time, the compound containing Li, the compound containing Na, the compound containing K, the compound containing Nb, the compound containing Ta, the compound containing Sb, and the above-mentioned additive are combined. When mixed at a stoichiometric ratio in consideration of substitution by a metal element contained in the additive, Li, Na, K, Nb, Ta, and Sb in the compound represented by the above general formula are mixed. At least a part of any one or more of them can be positively substituted by the metal element contained in the additive.

The above “mixing at a stoichiometric ratio in consideration of the substitution by the metal element contained in the additive” refers to, for example, a case where Li of the compound represented by the general formula is substituted for the metal element of the additive. Is to reduce the amount of the compound containing Li, add the above-mentioned additives by the reduced amount and mix, and as a whole, after firing, the general formula {Li _x (K _1-y Na _y ) _1-x } by such the compound represented by _{(Nb 1-zw Ta z Sb} w) O 3 are mixed at a stoichiometric ratio as synthesized, can be realized. In the case of substituting other atoms such as K, Na, Nb, Ta and Sb in the above general formula, the amount of the compound containing these should be reduced and an additive containing the metal element to be substituted should be added accordingly. Can be realized.

On the other hand, in the above general formula after firing _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) a compound represented by O ₃ such stoichiometric ratio, A compound containing Li, a compound containing Na, a compound containing K, a compound containing Nb, a compound containing Ta, and a compound containing Sb are mixed, and the above additive is added thereto. Is further mixed, whereby a piezoelectric ceramic composition containing the above-mentioned additive can be positively produced as a compound such as the above-mentioned metal element or an oxide containing the same or a perovskite structure compound.

  In the third aspect, the firing can be performed under normal pressure. Therefore, the piezoelectric ceramic composition can be manufactured easily and at low cost. The piezoelectric ceramic composition obtained after the above-mentioned firing does not contain lead, has a high apparent density, a small porosity and a small open porosity, and has excellent piezoelectric and dielectric properties as described above. Therefore, it can be used as a material for a piezoelectric element, a dielectric element, or the like, which has excellent mechanical strength and high performance.

  A fourth invention resides in a piezoelectric element having a piezoelectric body made of the piezoelectric ceramic composition of the first invention (claim 7).

The piezoelectric element according to the fourth aspect has a piezoelectric body made of the piezoelectric ceramic composition according to the first aspect (claim 1).
Therefore, the piezoelectric element does not contain lead and is environmentally safe.
Further, the piezoelectric element has excellent mechanical strength by utilizing the properties of the piezoelectric ceramic composition having a high apparent density and a low porosity and low open porosity.
Further, the piezoelectric element can utilize the property of the piezoelectric ceramic composition having excellent piezoelectric characteristics as it is. Therefore, the piezoelectric element can be used as a piezoelectric sensor element having high sensitivity, a piezoelectric vibrator having high electromechanical energy conversion efficiency, an actuator element, and the like.

  A fifth aspect of the present invention is a piezoelectric element having a piezoelectric body made of the piezoelectric ceramic composition manufactured by the manufacturing method of the second or third aspect (claim 8).

  The piezoelectric element according to the fifth aspect of the present invention has a piezoelectric body made of the piezoelectric ceramic composition obtained by the above-described manufacturing method. Therefore, the piezoelectric element can be used as a piezoelectric sensor element with high mechanical strength and high sensitivity, a piezoelectric vibrator and an actuator element with high electromechanical energy conversion efficiency, etc., by taking advantage of the excellent characteristics of the piezoelectric ceramic composition as it is. Can be used.

  A sixth invention resides in a dielectric element having a dielectric made of the piezoelectric ceramic composition of the first invention (claim 9).

  The dielectric element according to the sixth aspect has a dielectric made of the piezoelectric ceramic composition according to the first aspect (claim 1). Therefore, the dielectric element does not contain lead and is environmentally safe. In addition, the dielectric element is excellent in mechanical strength and further excellent in dielectric properties such as relative dielectric constant, utilizing the characteristics of the piezoelectric ceramic composition as it is. Therefore, it can be used as a capacitor having a large capacitance.

  A seventh aspect of the present invention resides in a dielectric element having a dielectric comprising a piezoelectric ceramic composition manufactured by the manufacturing method of the second or third aspect of the invention (claim 10).

  The dielectric element of the seventh invention has a dielectric made of the piezoelectric ceramic composition obtained by the above-described manufacturing method. Therefore, the dielectric element can be utilized as a capacitor or the like having excellent mechanical strength and a large capacitance by utilizing the excellent characteristics of the piezoelectric ceramic composition as it is.

In the present invention, the above general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) compound represented by the O ₃ is, x, y, z, a range of w Are respectively in 0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4 and 0 <w ≦ 0.2.
Here, in the case of x> 0.2, z> 0.4, w> 0.2, z = 0, or w = 0, the piezoelectric characteristics and dielectric characteristics such as a piezoelectric d ₃₁ constant is lowered, practically It may not be possible to obtain a piezoelectric ceramic composition having characteristics that can withstand high temperatures.
In the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) compound represented by O _3, the range of y is, 0 ≦ y ≦ 0. It is more preferably 85, and further preferably 0.05 ≦ y ≦ 0.75. In these cases, the piezoelectric d31 constant and the electromechanical coupling coefficient Kp of the piezoelectric ceramic composition can be further improved. Still more preferably, 0.05 ≦ y <0.75, more preferably 0.35 ≦ y ≦ 0.65, and even more preferably 0.35 ≦ y <0.65. Most preferably, 0.42 ≦ y ≦ 0.60 is good.

As described above, the piezoelectric ceramic composition contains a compound having a perovskite structure (ABO ₃ ) as a main component. In the present invention, the element configuration of the A site in the perovskite structure (ABO ₃ ) corresponds to K, Na or K, Na, and Li, and the element configuration of the B site corresponds to Nb, Ta, and Sb. In the composition formula of the perovskite structure, when the stoichiometric ratio of the atoms constituting the A site and the atoms constituting the B site is 1: 1, a complete perovskite structure is obtained. In particular, K, Na, Li, and Sb are volatilized by several%, specifically, about 3% in a firing step or the like, and all constituent elements are mixed by several% in a mixing pulverization or granulation step, and specifically, It may fluctuate by about 3%. That is, the stoichiometric composition may fluctuate due to variations in the manufacturing method.

  In order to cope with such compositional fluctuations in the manufacturing process, the compositional ratio of the piezoelectric ceramic composition after firing is increased by ± several%, more specifically ± 3 to 5 by intentionally changing the composition ratio. %. This is the same for, for example, the conventional zirconate titanate (PZT), and the mixing ratio is adjusted in consideration of the evaporation of lead during firing and the incorporation of zirconia from zirconia balls as grinding media. be able to.

In the piezoelectric ceramic composition of the present invention, electrical characteristics such as piezoelectric characteristics do not significantly change even if the composition ratio is intentionally changed as described above.
Accordingly, in the present invention, the general formula _{Li x (K 1-y Na} y) 1-x} (Nb 1-zw Ta z Sb w) compound represented by O _3, this a perovskite structure formula When applied to ABO ₃ , the composition ratio of A-site atoms and B-site atoms can be shifted to about ± 5 mol% with respect to 1: 1. In order to reduce lattice defects in the formed crystal and obtain high electrical characteristics, the composition is preferably up to about ± 3%.
That is, the general compound of formula as the main component of the piezoelectric ceramic _{composition, [Li x (K 1-} y Na y) 1-x] a {(Nb 1-zw Ta z Sb w)} _b O ₃ (0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4, 0 <w ≦ 0.2, 0.95 ≦ a, b ≦ 1.05) Including. Further, as described above, in the above equation, the range of a and b is preferably 0.97 ≦ a, b ≦ 1.03.

Similarly, the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) range of x of O ₃ is preferably 0 <x ≦ 0.2 .
In this case, since Li is an essential component, the piezoelectric ceramic composition can be more easily fired at the time of its manufacture, and can further improve the piezoelectric characteristics and further increase the Curie temperature. it can. This is because by making Li an essential component within the above range, the firing temperature is lowered, and Li plays the role of a firing aid, and firing with fewer pores is possible.

The value of the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3 of x may be a x = 0.
In this case, the general formula is represented by _{(K 1-y Na y)} (Nb 1-zw Ta z Sb w) O 3. In this case, when preparing the piezoelectric ceramic composition, since the raw material does not include a compound containing the lightest Li such as LiCO ₃ , the raw materials are mixed and the piezoelectric ceramic is mixed. Variations in characteristics due to segregation of the raw material powder when producing the composition can be reduced. In this case, a high relative dielectric constant and a relatively large piezoelectric g constant can be realized.

  Further, in the first invention, the piezoelectric ceramic composition comprises Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, Any one or more metal elements selected from V, Y, Yb, Zn, and Zr are contained as additive elements, and the total content of the additives is based on 1 mol of the compound represented by the general formula. 0.0005 mol to 0.15 mol.

If the total content of the additional elements is less than 0.0005 mol, the effect of high apparent density and low porosity and open porosity may not be sufficiently obtained. On the other hand, when the sum of the contents exceeds 0.15 mol, sintering becomes difficult when producing the piezoelectric ceramic composition. Further, after sintering, a crystal phase different from the crystal structure of the base composition may appear, and the apparent density of the piezoelectric ceramic composition after sintering may decrease. In addition, voids may be generated on the surface or inside of the piezoelectric ceramic composition, resulting in an increase in porosity and open porosity, and a decrease in mechanical strength of the piezoelectric ceramic composition.
The contents of the above-mentioned additional elements are Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, It is the number of moles of each metal element of Zn and Zr.

  In addition, the additive element may include at least a part of any one or more of Li, K, Na, Nb, Ta, and Sb of the compound represented by the general formula, and may include the Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr It can be in the form of a metal element or a compound containing the same, such as an oxide or a perovskite structure compound, which exists in a grain or a grain boundary in the piezoelectric ceramic composition.

  In the piezoelectric ceramic composition of the present invention, even if the above-mentioned additive is contained in any of the two forms described above, the additive exhibits the same excellent apparent density, open porosity, and porosity. it can.

The open porosity of the piezoelectric ceramic composition is 0.4 Vol% or less.
When the open porosity of the piezoelectric ceramic composition exceeds 0.4 Vol%, the mechanical strength of the piezoelectric ceramic composition becomes insufficient, and it may be difficult to apply the piezoelectric ceramic composition to a piezoelectric element or a dielectric element.

Next, it is preferable that the apparent density of the piezoelectric ceramic composition is represented by the general formula and is higher than the apparent density of the piezoelectric ceramic composition not containing the additional element.
When the apparent density of the piezoelectric ceramic composition is smaller than the apparent density of the piezoelectric ceramic composition represented by the general formula and not containing the additional element (hereinafter, referred to as a basic piezoelectric ceramic composition as appropriate), Not only can the effect of the additive not be sufficiently obtained, but also the mechanical strength of the piezoelectric ceramic composition may be insufficient.

  As described above, the expression “larger than the apparent density of the piezoelectric ceramic composition not containing the additive element represented by the general formula” means that the apparent density of the piezoelectric ceramic composition containing the additive element is the This means that it is larger than the basic piezoelectric ceramic composition having the basic composition of the porcelain composition and not containing the additional element.

Next, at least one of the porosity and the open porosity of the piezoelectric ceramic composition is represented by the general formula, and is smaller than the porosity or the open porosity of the piezoelectric ceramic composition containing no additional element. , Preferably smaller (claim 3).
If the porosity or open porosity of the piezoelectric ceramic composition (basic piezoelectric ceramic composition) which is represented by the above general formula and does not contain the above-mentioned additive element is smaller than the above, the effect of the above-mentioned additional element is sufficiently obtained. In addition to this, the mechanical strength of the piezoelectric ceramic composition may be insufficient.

  The above-mentioned “smaller than the porosity or open porosity of the piezoelectric ceramic composition not represented by the general formula and containing the additive element” means that the piezoelectric ceramic composition containing the additive element does not This means that the porosity or open porosity is smaller than that of the basic piezoelectric ceramic composition having the basic composition of the piezoelectric ceramic composition and not containing the above-mentioned additional element.

  In the second (claim 4) or the third invention (claim 5), the additives include Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Examples include any one or more metal elements selected from Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, and Zr, and compounds containing these metal elements.

As a result of adding the additives, as the metal element additive element contained in the additive formula after the burning _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb _w ) Li, K, Na, Nb, Ta, and Sr of the compound represented by O ₃ may be substituted for at least a part of the compound and contained in the piezoelectric ceramic composition. In addition, the metal element or a compound containing the metal element, such as an oxide or a perovskite structure compound, may be contained in the piezoelectric ceramic composition in a grain or a grain boundary.

Next, in the third invention (claim 5), the compound containing lithium includes, for example, Li ₂ CO ₃ , Li ₂ O, LiNO ₃ , and LiOH. The sodium-containing compounds include Na ₂ CO ₃ , NaHCO ₃ and NaNO ₃ .

Examples of the potassium-containing compound include K ₂ CO ₃ , KNO ₃ , KNbO ₃ , and KTaO ₃ . Examples of the compound containing the above-mentioned niobium, for example _{Nb 2 O 5, Nb 2 O} 3, there is NbO ₂ and the like. Examples of the tantalum-containing compound include Ta ₂ O ₅ . Examples of the compound containing the above antimony, for example, a _{Sb 2 O 5, Sb 2 O} 3, Sb 2 O 4 or the like.

Next, the compound containing Li is Li ₂ CO ₃ , the compound containing Na is Na ₂ CO ₃ , the compound containing K is K ₂ CO ₃ , the compound containing Nb is Nb ₂ O ₅ , The Ta-containing compound is Ta ₂ O ₅ , the Sb-containing compound is Sb ₂ O ₅ or Sb ₂ O ₃ , and the additive is Ag ₂ O, Al ₂ O ₃ , Au, Au ₂ O ₃ , B ₂ O ₃ , H ₃ BO ₃ , BaO, BaO ₂ , BaCO ₃ , Bi ₂ O ₃ , CaO, CaCO ₃ , CeO ₂ , Ce ₂ (CO ₃ ) ₃ , CoO, Co ₃ O ₄ , CoCO ₃ , Cs _{2 CO 3, CuO, Cu 2 O} , Dy 2 O 3, Er 2 O 3, Eu 2 O 3, Fe 2 O 3, Ga 2 O 3, Gd 2 O 3, GeO 2, HfO 2, Ho 2 O 3, _{In 2 O 3, IrO 2,} Ir 2 O 3, La 2 O 3, Lu 2 O 3, MgO, MgC 2 O 4, MnO _{MnO 2, Mn 2 O 3,} Mn 3 O 4, Nd 2 O 3, Nd 2 CO 3, NiO, NiCO 3, PdO, Pr 2 O 3, Pr 6 O 11, Pr 2 (CO 3) 3, PtO 2 _{, Rb 2 O, Rb 2 CO} 3, Re 2 O 7, RuO 2, Sc 2 O 3, SiO 2, SiO, SiC, Sm 2 O 3, SnO, SnO 2, SrO, SrCO 3, Tb 4 O 7, _{TiO, Ti 2 O 3, TiO} 2, Tm 2 O 3, V 2 O 3, V 2 O 4, V 2 O 5, Y 2 O 3, Y 2 (CO 3) 3, Yb 2 O 3, ZnO, It is preferably at least one selected from ZrO ₂ (claim 6).
In this case, the piezoelectric ceramic composition can be easily produced.

  Next, in the fourth (claim 7) or the fifth invention (claim 8), the piezoelectric element includes, for example, a piezoelectric actuator, a piezoelectric filter, a piezoelectric vibrator, a piezoelectric transformer, a piezoelectric ultrasonic motor, a piezoelectric gyro. There are sensors, knock sensors, yaw rate sensors, airbag sensors, back sonars, corner sonars, piezoelectric buzzers, piezoelectric speakers, and piezoelectric igniters.

  Next, in the sixth (invention 9) or the seventh invention (invention 10), examples of the dielectric element include a capacitor and a multilayer capacitor.

(Example 1)
Next, a piezoelectric ceramic composition according to an example of the present invention will be described.
In this example, the piezoelectric ceramic composition was prepared and its characteristics were evaluated.
The piezoelectric ceramic composition of this example is represented by the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w Are piezoelectric ceramic compositions containing, as main components, compounds having composition ranges of 0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4, and 0 <w ≦ 0.2, respectively. The piezoelectric ceramic composition comprises Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir. , La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr Any one of metal elements selected from the group consisting of: The content of the additional element is 0.01 mol based on 1 mol of the compound represented by the general formula. The open porosity of the piezoelectric ceramic composition is 0.4 Vol% or less.

The method for producing the piezoelectric ceramic composition of the present example comprises a compound containing Li, a compound containing Na, a compound containing K, a compound containing Nb, a compound containing Ta, and a compound containing Sb. with a compound of the general formula after calcination _{{Li x (K 1-y} Na y) 1-x} is represented by _{(Nb 1-zw Ta z Sb} w) O 3, and x, y, z, w, respectively The compounds are mixed at a stoichiometric ratio such that the compounds fall within the composition ranges of 0 ≦ x ≦ 0.2, 0 ≦ y ≦ 1, 0 <z ≦ 0.4, and 0 <w ≦ 0.2. , Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn , Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Y , Zn, a mixture of additives comprising any one metal element selected from Zr, calcined.

Hereinafter, the method for producing the piezoelectric ceramic composition of the present example will be described in detail.
First, high-purity Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , and Sb ₂ O having a purity of 99% or more were used as raw materials for the basic composition of the piezoelectric ceramic composition. Prepared ₅ .

Next, these raw materials and Ag ₂ O, Al ₂ O ₃ , Au, Au ₂ O ₃ , B ₂ O ₃ , H ₃ BO ₃ , BaO, BaO ₂ , BaCO ₃ , and Bi ₂ O as the above additives are added. _{3, CaO, CaCO 3, CeO} 2, Ce 2 (CO 3) 3, CoO, Co 3 O 4, CoCO 3, Cs 2 CO 3, CuO, Cu 2 O, Dy 2 O 3, Er 2 O 3, Eu ₂ O ₃ , Fe ₂ O ₃ , Ga ₂ O ₃ , Gd ₂ O ₃ , GeO ₂ , HfO ₂ , Ho ₂ O ₃ , In ₂ O ₃ , IrO ₂ , Ir ₂ O ₃ , La ₂ O ₃ , Lu _{2 O 3, MgO, MgC 2 O} 4, MnO, MnO 2, Mn 2 O 3, Mn 3 O 4, Nd 2 O 3, Nd 2 CO 3, NiO, NiCO 3, PdO, Pr 2 O 3, Pr 6 O ₁₁ , Pr ₂ (CO ₃ ) ₃ , PtO ₂ , Rb ₂ O, Rb ₂ CO ₃ , Re ₂ O ₇ , RuO ₂ , Sc ₂ O ₃ , SiO ₂ , SiO _{, SiC, Sm 2 O 3,} SnO, SnO 2, SrO, SrCO 3, Tb 4 O 7, TiO, Ti 2 O 3, TiO 2, Tm 2 O 3, V 2 O 3, V 2 O 4, V 2 Any one of the compositions of O ₅ , Y ₂ O ₃ , Y ₂ (CO ₃ ) ₃ , Yb ₂ O ₃ , ZnO, and ZrO ₂ was converted to a compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ was blended with a composition such that the metal element contained in each of the above-mentioned additives was contained in the piezoelectric ceramic composition to obtain 47 kinds of blends. The added element may be present in the crystal grains of the piezoelectric ceramic composition or at the grain boundaries.

Regarding the compounding amount of the above-mentioned additive, 1 mol of compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O _3, which is expected to be obtained after baking with the above stoichiometric ratio , With the addition amounts shown in Tables 1 and 2 described below. At this time, the content of each additive was such that the amount of the metal element contained in the additive was 0.01 mol regardless of which additive was contained.

Subsequently, each compound was mixed in acetone by a ball mill for 24 hours to prepare a mixture.
Next, each mixture was calcined at a temperature of 750 ° C. for 5 hours, and then each of the calcined mixtures was pulverized by a ball mill for 24 hours. Subsequently, polyvinyl butyral was added as a binder and granulated.

Each of the granulated powders is pressed at a pressure of ² ton / cm ² into a disc having a diameter of 13 mm and a thickness of 2 mm, and the obtained compact is fired at a temperature of 1000 to 1300 ° C. for 1 hour. Was prepared. The specific firing temperature at this time was selected from the above-mentioned temperature range of 1000 ° C. to 1300 ° C. at which a fired body having the maximum density can be obtained by firing for one hour. At this time, all of the fired bodies were densified to a relative density of 98% or more.

Next, both sides of each fired body were polished in parallel and circularly polished, and then gold electrodes were provided on both sides of the disk sample by sputtering. Then, a DC voltage of 1 to 5 kV / mm was applied between the electrode layers in a silicone oil at 100 ° C. for 10 minutes, and polarization was performed in the thickness direction to obtain a piezoelectric ceramic composition.
Thus, 47 types of piezoelectric ceramic compositions (samples E1 to E47) were prepared. The types and amounts of additives in each sample are shown in Tables 1 and 2 below.

Further, as a method different from the production method of this example, a compound represented by the above {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ is produced by firing, and this is pulverized. Even if the mixture is mixed with the above additives, and then calcined, granulated, molded and fired in the same manner as in the production method of this example, a piezoelectric ceramic composition similar to the above-mentioned samples E1 to E47 can be produced.

Next, in this example, in order to clarify the excellent characteristics of the piezoelectric ceramic composition (samples E1 to E47), three types of comparative products (samples C1 to C3) were prepared as follows.
First, high-purity Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , Sb ₂ O ₅ , MoO ₃ , WO with a purity of 99% or more are used as raw materials for comparative products. Prepared ₃ .

Among these raw materials, Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , and Sb ₂ O ₅ are converted into a compound {Li _0.04 (K _0.5 Na _0.5 ) after firing. _{It was} blended at a stoichiometric ratio such that _0.966 (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ to obtain a blend.
This composition was mixed in acetone using a ball mill for 24 hours, and calcined, granulated, molded, fired, and polarized in the same manner as in Samples E1 to E47. Sample C1) was produced. This sample C1 is a piezoelectric ceramic composition containing no additional element.

In addition, MoO ₃ or WO ₃ was added as an additive to the above-mentioned composition blended at a stoichiometric ratio such that {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O _3. Each was added to make two formulations. At this time, the additive amount of the additive is as shown in Table 2 described later.

Subsequently, each composition was mixed in acetone by a ball mill for 24 hours, and calcined, granulated, molded, fired, and polarized in the same manner as in Samples E1 to E47. Compositions (Sample C2 and Sample C3) were prepared. Sample C2 and Sample C3 were prepared by adding MoO ₃ or WO ₃ as an additive to the compound Li _0.04 (K _0.5 Na _0.5 ) _0.96 ｝ (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ , , Each containing 0.01 mol.

Next, the apparent densities and open porosity of the samples E1 to E47 and the samples C1 to C3 were measured. The results are shown in Tables 1 and 2.
The open porosity was measured by the following method.

(Open porosity)
First, weigh the sample and use it as the dry weight. Subsequently, the sample is completely immersed in water, subjected to vacuum degassing, and the sample is sufficiently absorbed with water. This sample is weighed by the Archimedes method in a state where the sample is submerged in water, and this is defined as the weight in water. The sample is then withdrawn from the water, excess water is removed and the sample is weighed again. This is defined as the wet weight.
Next, the open porosity (Vol%) of the sample was calculated from the dry weight, the weight in water, and the weight containing water obtained above using the following equation (1).
Open porosity (Vol%) = (Wet weight−Dry weight) / (Wet weight−Water weight) (Formula 1)

As is known from Tables 1 and 2, the piezoelectric ceramic compositions of Samples E1 to E47 have an apparent density higher than or equal to that of Samples C1 to C3 as comparative products, and also have an open porosity of 0. The value was as low as 4 Vol% or less.
Thus, it can be seen that the piezoelectric ceramic compositions of Samples E1 to E47 have excellent mechanical strength.

Although not shown in Tables 1 and 2, the piezoelectric and dielectric properties of the samples E1 to E47 were measured by a resonance-anti-resonance method using an impedance analyzer, and the piezoelectric ceramic compositions of the samples E1 to E47 were measured. things, the piezoelectric d ₃₁ constant, electromechanical coupling factor Kp, piezoelectric g ₃₁ constant, the mechanical quality factor Qm, dielectric constant, dielectric loss, and was excellent in piezoelectric characteristics and dielectric characteristics of the Curie temperature.
Therefore, the piezoelectric ceramic composition of this example can be used as a piezoelectric element and a dielectric element having excellent mechanical strength and high performance.

(Example 2)
In this example, the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3 ( where, 0 ≦ x ≦ 0.2,0 ≦ y ≦ 1 , 0 <z ≦ 0.4, 0 <w ≦ 0.2), at least a portion of Li, K, Na, Nb, Ta, and Sb of each of the compounds represented by the above-mentioned additives are substituted. In this state, a sample containing an additive (hereinafter referred to as a sample appropriately substituted and added) and a sample containing the above additive and added (hereinafter referred to as a sample appropriately added) are prepared. Compare their properties.

First, samples E1, E5, E7, E10, E25, E32, and E39 prepared in Example 1 were prepared as the above-mentioned externally added samples. These samples E1, E5, E7, E10, E25, E32, and E39 were prepared by adding the compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ Ag ₂ O, BaO, CaCO ₃ , Cs ₂ CO ₃ , MgO, Rb ₂ O, or SrCO ₃ were added as additives and synthesized.

Next, a sample to which the above-mentioned additives are added is prepared as follows.
First, as raw materials of the basic composition of the piezoelectric ceramic composition, high-purity Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , Sb ₂ O _{5 with} a purity of 99% or more. And Ag ₂ O, BaO, CaCO ₃ , Cs ₂ CO ₃ , MgO, Rb ₂ O, or SrCO ₃ as the additive.

Next, the raw material having the above basic composition and one of the above-mentioned additives are added to the compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ in the above-mentioned additive. Were blended at a stoichiometric ratio such that each of the metal elements was replaced and solid-dissolved after firing, thereby preparing seven types of blends. Specifically, {Li _0.04 (K _0.5 Na _0.5 ) _0.95 Ag _0.01 } (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ and {Li _0.04 (K _0.5 Na _0.5 ) _0.94 Ba _0.01 } (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ , {Li _0.04 (K _0.5 Na _0.5 ) _0.94 Ca _0.01 ｝ (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ , ｛Li _0.04 (K _0.5 Na _0.5 ) _0.95 Cs _0.01 ｝ (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ , ｛Li _0.04 (K _0.5 Na _0.5 ) _0.94 Mg _0.01 ｝ (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ , ｛Li _0.04 (K _0.5 Na _0.5 ) _0.95 Rb _0.01 ｝ (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ , {Li _0.04 (K _0.5 Na _0.5 ) _0.94 Sr _0.01 ｝ (Nb _0.86 Ta _0.10 Sb _0.04 ) O ₃ .
Subsequently, each compound was mixed in acetone by a ball mill for 24 hours to obtain a mixture.

Next, this mixture was calcined, granulated, molded, fired, and polarized in the same manner as the samples E1 to E47 of Example 1.
In this way, piezoelectric ceramic compositions were prepared by substituting Ag ₂ O, BaO, CaCO ₃ , Cs ₂ CO ₃ , MgO, Rb ₂ O, or SrCO ₃ as the above additives, and these were used as samples. E1a, E5a, E7a, E10a, E25a, E32a, and E39a.

  The sample E1 and the sample E1a, the sample E5 and the sample E5a, the sample E7 and the sample E7a, the sample E10 and the sample E10a, the sample E25 and the sample E25a, the sample E32 and the sample E32a, and the sample E39 and the sample E39a are the same metal elements. This is a piezoelectric ceramic composition containing an additive containing, and the former is an externally added sample, and the latter is a replacement-added sample.

  Next, the apparent density and open porosity of each of the above samples were measured. Table 3 shows the results. Table 3 also shows the apparent density and the open porosity of the sample C1 produced in Example 1 for comparison.

As can be seen from Table 3, Samples E1 and E1a, Samples E5 and E5a, Samples E7 and E7a, Samples E10 and E10a, Samples E25 and E25a, and Samples E32 and E32a were compared with Sample C1. As a result, the apparent density was equal to or more than that, and the open porosity was lower than that of the sample C1.
This indicates that the piezoelectric ceramic composition of this example has excellent apparent density and open porosity regardless of whether the above additives are externally added or replaced and added. .
Further, in the case of the sample 41 and the sample 41a containing Sr, a high apparent density and a low open porosity were obtained in the sample 41a having the substitution composition.

(Example 3)
This example is an example in which the amount of the above-mentioned additive was changed and contained in the piezoelectric ceramic composition.
First, as raw materials of the basic composition of the piezoelectric ceramic composition, high-purity Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , Sb ₂ O _{5 with} a purity of 99% or more. , And Bi ₂ O ₃ as the above additive were prepared.

Of these raw materials, Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , Nb ₂ O ₅ , Ta ₂ O ₅ , and Sb ₂ O ₅ are fired, and after firing, the above general formula {Li _x (K _{1− y Na y) 1-x}} (Nb 1-zw Ta z Sb w) at _{O 3, x, y, z} , w , respectively x = 0.04, y = 0.5, z = 0.1, w = 0.04, and Bi ₂ O ₃ as the above additive was further blended to obtain a blend.

At this time, Bi ₂ O ₃ as the additive is a compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) which is expected to be obtained by blending at the above stoichiometric ratio. 0.0025, 0.0005, or 0.00025 mol was added to 1 mol of O ₃ . That is, 0.005, 0.001, or 0.0005 mol of the metal element (Bi) in the additive was blended.
Then, each composition was mixed in acetone by a ball mill for 24 hours to prepare a mixture.

This mixture was calcined, granulated, molded, fired, and polarized in the same manner as in Samples E1 to E47 to obtain three types of piezoelectric ceramic compositions (Sample E6x, Sample E6y, and Sample E6z). Table 4 shows the types and amounts of additives in each sample.
Next, the apparent densities and open porosity of the samples E6x, E6y, and E6z were measured in the same manner as in Example 1. Table 4 shows the results.
In Table 4, for comparison, the results of the sample E6 prepared in Example 1 containing 0.01 mol of Bi as the additional element and the sample C1 containing no additional element are also shown. .

As can be seen from Table 4, Sample E6, Sample E6x, Sample E6y, and Sample E6z exhibited higher apparent density and lower open porosity than Sample C1. That is, in the piezoelectric ceramic composition of this example, the above additive was added to 1 mol of the compound {Li _0.04 (K _0.5 Na _0.5 ) _0.96 } (Nb _0.86 Ta _0.1 Sb _0.04 ) O ₃ , and the metal in the additive was added. By containing 0.0005 mol to 0.01 mol of the element, the apparent density and open porosity of the piezoelectric ceramic composition can be improved.

In general, the porosity increases as the open porosity increases. Therefore, the fact that the open porosity can be reduced by adding the additive as in the present invention means that the porosity is also reduced.

Claims (10)

It is represented by the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w respectively 0 ≦ x ≦ 0.2 , 0 ≦ y ≦ 1, 0 <z ≦ 0.4, 0 <w ≦ 0.2, a piezoelectric ceramic composition mainly comprising a compound in the composition range,
The piezoelectric ceramic composition comprises Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir. , La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr One or more metal elements selected from the group consisting of
The total content of the additional elements is 0.0005 mol to 0.15 mol with respect to 1 mol of the compound represented by the general formula.
A piezoelectric ceramic composition having an open porosity of 0.4 Vol% or less.   2. The piezoelectric ceramic composition according to claim 1, wherein the apparent density of the piezoelectric ceramic composition is represented by the general formula and is larger than the apparent density of the piezoelectric ceramic composition containing no additional element. .   3. The porosity or open porosity of the piezoelectric ceramic composition according to claim 1 or 2, wherein at least one of the porosity and the open porosity of the piezoelectric ceramic composition is represented by the general formula, and the porosity or the open porosity of the piezoelectric ceramic composition not containing the additional element. A piezoelectric ceramic composition characterized by having a porosity smaller than the porosity. It is represented by the general formula _{{Li x (K 1-y} Na y) 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w respectively 0 ≦ x ≦ 0.2 , 0 ≦ y ≦ 1, 0 <z ≦ 0.4, 0 <w ≦ 0.2, a compound having a composition range of Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, A piezoelectric element characterized by mixing with an additive containing at least one metal element selected from Si, Sm, Sn, Sr, Tb, Ti, Tm, V, Y, Yb, Zn, and Zr, followed by firing. A method for producing a porcelain composition. A compound containing Li, a compound containing Na, a compound containing K, a compound containing Nb, a compound containing Ta, and a compound containing Sb are fired to obtain a compound of the general formula {Li _x It is represented by _{(K 1-y Na y)} 1-x} (Nb 1-zw Ta z Sb w) O 3, and x, y, z, w respectively 0 ≦ x ≦ 0.2,0 ≦ y ≦ Considering substitution at a stoichiometric ratio so as to be a compound in the composition range of 1,0 <z ≦ 0.4 and 0 <w ≦ 0.2, or with a metal element contained in the following additives: Ag, Al, Au, B, Ba, Bi, Ca, Ce, Co, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Ho, In, Ir, La, Lu, Mg, Mn, Nd, Ni, Pd, Pr, Pt, Rb, Re, Ru, Sc, Si, Sm, S , Sr, Tb, Ti, Tm, V, Y, Yb, Zn, Zr, and an additive containing at least one metal element selected from the mixture, and baked. Method. The compound containing Li is Li ₂ CO ₃ , the compound containing Na is Na ₂ CO ₃ , the compound containing K is K ₂ CO ₃ , and the compound containing Nb is Nb ₂ O. ₅ , the Ta-containing compound is Ta ₂ O ₅ , the Sb-containing compound is Sb ₂ O ₅ or Sb ₂ O ₃ , and the additive is Ag ₂ O, Al ₂ O ₃ , Au, Au ₂ O _{3 , B 2 O 3, H 3} BO 3, BaO, BaO 2, BaCO 3, Bi 2 O 3, CaO, CaCO 3, CeO 2, Ce 2 (CO 3) 3, CoO, Co 3 O 4, CoCO 3, Cs ₂ CO ₃ , CuO, Cu ₂ O, Dy ₂ O ₃ , Er ₂ O ₃ , Eu ₂ O ₃ , Fe ₂ O ₃ , Ga ₂ O ₃ , Gd ₂ O ₃ , GeO ₂ , HfO ₂ , Ho ₂ O _{3, In 2 O 3, IrO} 2, Ir 2 O 3, La 2 O 3, Lu 2 O 3, MgO, MgC 2 _{4, MnO, MnO 2, Mn} 2 O 3, Mn 3 O 4, Nd 2 O 3, Nd 2 CO 3, NiO, NiCO 3, PdO, Pr 2 O 3, Pr 6 O 11, Pr 2 (CO 3) ₃ , PtO ₂ , Rb ₂ O, Rb ₂ CO ₃ , Re ₂ O ₇ , RuO ₂ , Sc ₂ O ₃ , SiO ₂ , SiO, SiC, Sm ₂ O ₃ , SnO, SnO ₂ , SrO, SrCO ₃ , Tb _{4 O 7, TiO, Ti 2} O 3, TiO 2, Tm 2 O 3, V 2 O 3, V 2 O 4, V 2 O 5, Y 2 O 3, Y 2 (CO 3) 3, Yb 2 O ₃ , a method for producing a piezoelectric ceramic composition, which is at least one selected from ZnO and ZrO ₂ .   A piezoelectric element comprising a piezoelectric body made of the piezoelectric ceramic composition according to claim 1.   A piezoelectric element comprising a piezoelectric body made of the piezoelectric ceramic composition manufactured by the manufacturing method according to claim 4.   A dielectric element comprising a dielectric comprising the piezoelectric ceramic composition according to claim 1.   A dielectric element comprising a dielectric made of the piezoelectric ceramic composition manufactured by the manufacturing method according to claim 4.