SU1428744A1 - Piezoelectric ceramic material - Google Patents

Abstract

The invention relates to the field of piezotechnics and can be used to create high-frequency electromechanical transducers based on the phenomenon of piezoelectricity, in particular in ultrasonic delay lines, mono-frequency resonators li. accelerometers. To reduce the sintering temperature and increase the volume piezomodule, bismuth oxide was additionally introduced into the solid solution of lithium-niobate niobate in the following ratio of components, wt%: LijO 1.0-1.3; 16.5-16.7; 81.3-82.1; Bi, jO, 0.1-0.8; 1-0.2. The material has the following properties: sintering temperature 1120-1140 ° C, density 4.27-4.46 g / cm, dielectric constant 5 about 61-63, dielectric loss tangent tg 5 0.1-0.2%, piezoelectric modules: d3, (4.8-5.4) IO-C / H and d, (51.1-57.2), volume piezomodule, 10.2-10.7, coefficient of electromechanical communication : Cr 0.17-0.20, sound speed V

Description

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The invention relates to a piezotechnique and can be used to create high-frequency electromechanical transducers, in particular, for ultrasonic lines. handles.

The purpose of the invention is to reduce the sintering temperature and increase the volumetric piezomodule.

Ceramics based on sodium niobate modified with strontium and titanium oxides are obtained from lithium carbonate, sodium, bismuth oxides and titanium of the brand Chood.

The components are mixed and ground in a gambe drum in absolute alcohol, grinding time 12 hours. After drying at 200-250 ° C, the material is calcined in a powdery state at 800 ° C for 4 hours, then crushed to pass through a 10000 sieve ./cm then press disks with a diameter of 12 mm and a thickness of 2 mm.

A 3% aqueous solution of polyvinyl alcohol is used as a binder. Sintering was carried out at 1120-1 14 ° C with a cone of 1 h. Electrodes were deposited on ground disks by sputtering aluminum in a vacuum. Polarization is carried out in a polysiloxane fluid at 150 ° C and a field strength of 50–70 kV / cm.

Claims (2)

The chemical composition of the material is given in table. 1, properties - in the table. 2. The formula of the invention The piezoelectric ceramic material, including, Li O, is an additive, characterized in that, in order to reduce the sintering temperature and turn of the bulk piezoelectric module, it contains BijO as an additive, in the following ratio, wt.%: Nb, b581,3-82,1 Na.jO. 16.3-16.7 , 0-1.3 1-0.8 Ti020.1-0.2. Dielectric constant. 62 63 Table 1 table 2 61 61 63 65-70 Piezoelectric module a „-10, C / N Volume piezomodul djj / dji Electromechanical coefficient  Prodochene table.2 55.2 56.0 55.3 110-130 10.6 10.6 10.6 4.7