SU1133249A1 - Piezoelectric ceramic material - Google Patents

Abstract

PIEZOELECTRIC 1SCRAMIC MATERIAL is mainly for frequency-selective devices, containing PbTiO, PbZrOj, PbW.jiin.jOj, characterized in that, in order to increase the electromechanical coupling coefficient at high temperature stability of the resonance frequency and the mechanical factor, there is an addition, in addition to the addition of an additional option. the following ratio of components, mol.%: 45.00 47.45 PbTr 39.96 38.20 PbZrOj 11.53 10.77 Pb№5 ,, Oz 3.40 3.35. PbASjO 0.25 0.10

Description

O9

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CD The invention relates to piezoelectric ceramic materials and can be used in radio electronics to create selective device frequencies (CSNs), often for broadband filters. Piezoceramic materials based on multicomponent systems of ferroelectric solid solutions for use in filter technology are known. However, these materials have either not sufficiently high values of Kp, or not enough high temperature stability of the resonance frequency, or a low mechanical quality factor. The closest to the invention is a technical solution a piez electric ceramic material. 12, which represents the ltf component system, including PbTiO, PbZrOj, PbNb2 / 3Mn j3 3 PbW. P the following ratio of components, mol.%: PbTiOg20,0 - 80,0 8,40 - 70,40 PbZrOj PbNb, /, Mn, jO 1,30 - 8,91 0,30 - 3,36 However, one of the compositions, The best point of view of using it in CSU has, 357,, el / 830,, 24% in the interval -. The presence in the system of only one. Stable composition with insufficiently high Cp does not allow

Table 1 Let us use this material in broadband filters. The purpose of the invention is to increase the electromechanical coupling coefficient at a high temperature stability of the resonant frequency and mechanical quality factor. This goal is achieved by the fact that a piezoelectric ceramic material containing PbTiOj, PbZrO, PbNb ,, additionally contains FbAe 0 while also containing the ratio of the components, mol.%: PH Gyuz45,00 47, 45 PbZrOj: 38,20 39, 96 Mp IO 10.77 11, 53. PbW, / 2 3,40 3,35 РЬАВз 0 0,10 0, 25 Synthesis of the compositions of the piezoceramic material being sold is carried out by conventional ceramic technology by double firing: temperature T 800 C, duration 5 hours. Sintering is carried out in a closed alundum crucible for 1 h. The sintering temperature is 1200–1225 ° С. All samples are polarized in silicone oil at 140 ° C for 45 minutes in a field of 40–44 kV / cm, followed by cooling under a field to 90 ° C. Data on the dielectric and piezoelectric characteristics of the material to be given are given in Table. one. .

0.10 0.20 0.10 0.25 0.50 0.05

As can be seen from the table. 1, the proposed material has significantly higher values compared with the known value of C25 of 0.44 0.44 - 0.49. At the same time, a sufficiently high mechanical quality factor Qj 1200 1500 is maintained. The value of (ff 9 / fi is practically unchanged compared with the known JQ material. The dielectric constant E varies from 900 to 1000. The best combination of parameters is achieved in part 1

, (CRO, 47; Qj, 1.500;

  35 900 - 1000 0.44 Offered Known 830 0.357

The achieved level of values of Kp in the proposed material is much higher than in the known, the continuation of table 1

ff9 / fr 0,24%) and the composition of 2 (1000; Croo, 49; Q 1200; cAfe / frO, 25%)

Examples 5 and 6 (Table 1) demonstrate the deterioration of properties outside the proposed concentration range, violation of these limits leads to a deterioration in the temperature stability of the resonance frequency, to a decrease in Kp or 0.

In tab. Figure 2 shows the electrophysical parameters of the proposed and known materials.

table 2

bark it promising for efficient foot use in broadband filters. 0.49 1200 - 1500 0.23 - 0.25 2570 0.24

51133249; 6

The combination in the proposed material of the objects of electronic equipment of high values of mechanical engineering, which use devices with high temperature for stabilization and filtering

stability is a very beneficial operating frequency of electrical circuits, which is convenient, as it allows to improve 5. An important advantage of the proposed broadband filter material is the ability to

ditch (tuning accuracy, sharping it in the usual ceramic

bandwidth, stability technology, which simplifies the process

for temperature, etc.), simplify production and saves expensive circuit solutions, increase reliable equipment.

Claims (1)

Piezoelectric ceramic material mainly for frequency-selective devices containing PbTiO ^, PbZrO ₃ , PbNb ₂ j ₃ Mn ^ O ₃ РЬИ ^ Мп ^ Оj, characterized in that, in order to increase the coefficient of electromechanical coupling at high temperature stability of the resonant frequency and mechanical Q, does it additionally contain PBA? ₂ About ₄ in the following ratio of components, mol.%: PbTiO ₃ PbZrOj PbNb _2/3 Mn _{4) s} Oj Pbw _{4 (2} Μη _1/2 0 ₃ pbAe ₂ o ₄ 45.00 - 47.45 38.20 - 39.96 10.77 - 11.53 3.35 - 3.40 0.10 - 0.25 SU. ,,, 11332 1 .1133249