Piezoelectric porcelain composition, and piezoelectric ceramic electronic component
A piezoelectric porcelain composition includes a main ingredient represented by a general formula ((1−x)(K 1−a−b Na a Li b ) (Nb 1−c Ta c )O 3 −xM2M4O 3 ) (where M2 represents Ca, Ba or Sr, M4 represents Zr, Sn or Hf, and 0.005≦x≦0.1, 0≦a≦0.9, 0≦b≦0.1, 0≦a+b≦0.9, and 0≦c≦0.3), and Mn is contained in an amount ranging from 2 to 15 mol, relative to 100 mol of the main ingredient, and the M4 is contained in an amount ranging from 0.1 to 5.0 mol, relative to 100 mol of the main ingredient. Preferably, Ni is contained in an amount ranging from 0.1 to 5.0 mol, relative to 100 mol of the main ingredient, and also preferably Yb, In and the like specific rare earth elements is contained. A ceramic layer in a ceramic base is formed of this piezoelectric porcelain composition. As a result, the degree of sintering in a reductive atmosphere is improved, and a piezoelectric porcelain composition allowing co-sintering with Ni, and a piezoelectric ceramic electronic component using the same are realized.
1. A piezoelectric porcelain composition comprising
100{(1−x)(K 1−a−b Na a Li b )(Nb 1−c Ta c )O 3 −xM2M4O 3 }+αMn+βM4
wherein the main ingredient is represented by the general formula
((1−x)(K 1−a−b Na a Li b )(Nb 1−c Ta c )O 3 −xM2M4O 3 )
in which M2 is at least one member selected from the group consisting of Ca, Ba and Sr, M4 is at least one member selected from the group consisting of Zr, Sn and Hf, 0.005≦x≦0.1, 0≦a≦0.9, 0≦b≦0.1, 0≦a+b≦0.9, and 0≦c≦0.3,
the amount α of Mn ranges from 2 to 15 mols, relative to 100 mol of the main ingredient, and
the amount β of M4 ranges from 0.1 to 5.0 mols, relative to 100 mol of the main ingredient,
said piezoelectric porcelain composition has the property of being co-sinterable with Ni electrodes in a reducing atmosphere.
2. The piezoelectric porcelain composition according to claim 1 , further comprising Ni in an amount ranging from 0.1 to 5.0 mols, relative to 100 mol of the main ingredient.
3. The piezoelectric porcelain composition according to claim 2 , further comprising at least one element selected from the group consisting of Sc, In, Yb, Y, Nd, Eu, Gd, Dy, Sm, Ho, Er, Tb, Lu, La, and Pr in an amount ranging from 0.1 to 5.0 mols, relative to 100 mol of the main ingredient.
4. The piezoelectric porcelain composition according to claim 3 , wherein the amount α of Mn ranges from 5 to 10 mols relative to 100 mol of the main ingredient.
5. The piezoelectric porcelain composition according to claim 4 , wherein the amount β of M4 ranges from 1 to 5 mols relative to 100 mol of the main ingredient.
6. The piezoelectric porcelain composition according to claim 1 , further comprising at least one element selected from the group consisting of Sc, In, Yb, Y, Nd, Eu, Gd, Dy, Sm, Ho, Er, Tb, Lu, La, and Pr in an amount ranging from 0.1 to 5.0 mols, relative to 100 mol of the main ingredient.
7. The piezoelectric porcelain composition according to claim 6 , wherein the amount α of Mn ranges from 5 to 10 mols relative to 100 mol of the main ingredient.
8. The piezoelectric porcelain composition according to claim 7 , wherein the amount β of M4 ranges from 1 to 5 mols relative to 100 mol of the main ingredient.
9. The piezoelectric porcelain composition according to claim 1 , wherein the amount α of Mn ranges from 5 to 10 mols relative to 100 mol of the main ingredient.
10. The piezoelectric porcelain composition according to claim 1 , wherein the amount β of M4 ranges from 1 to 5 mols relative to 100 mol of the main ingredient.
11. A piezoelectric ceramic electronic component having an external electrode on a surface of a piezoelectric ceramic base, wherein the piezoelectric ceramic base is a piezoelectric porcelain composition according to claim 1 .
12. The piezoelectric ceramic electronic component according to claim 11 in which the piezoelectric ceramic base is a sintered stack of alternating internal electrode and piezoelectric ceramic composition layer.
13. The piezoelectric ceramic electronic component according to claim 12 , wherein the internal electrode comprises Ni.
14. A piezoelectric ceramic electronic component having an external electrode on a surface of a piezoelectric ceramic base, wherein the piezoelectric ceramic base is a piezoelectric porcelain composition according to claim 2 .
15. The piezoelectric ceramic electronic component according to claim 14 in which the piezoelectric ceramic base is a sintered stack of alternating internal electrode and piezoelectric ceramic composition layer.
16. The piezoelectric ceramic electronic component according to claim 15 , wherein the internal electrode comprises Ni.
17. A piezoelectric ceramic electronic component having an external electrode on a surface of a piezoelectric ceramic base, wherein the piezoelectric ceramic base is a piezoelectric porcelain composition according to claim 3 .
18. The piezoelectric ceramic electronic component according to claim 17 in which the piezoelectric ceramic base is a sintered stack of alternating internal electrode and piezoelectric ceramic composition layer.
19. The piezoelectric ceramic electronic component according to claim 18 , wherein the internal electrode comprises Ni.
20. A piezoelectric ceramic electronic component having an external electrode on a surface of a piezoelectric ceramic base, wherein the piezoelectric ceramic base is a piezoelectric porcelain composition according to claim 6 .
21. A piezoelectric ceramic electronic component comprising a reducing atmosphere co-sintered combination of piezoelectric ceramic and at least one Ni electrode, wherein the piezoelectric ceramic is a piezoelectric porcelain composition according to claim 1 .
22. A method of forming a piezoelectric ceramic electronic component comprising sintering in a reductive atmosphere a stack comprising a Ni electrode sandwiched between a pair of layers of piezoelectric porcelain composition according to claim 1 .