SU963573A1 - Piezoelement production method - Google Patents

Description

The invention relates to methods for manufacturing piezoelectric elements, and can be used in the manufacture of piezo transducers used to measure the level of flow. liquefied gases at low and ultralow temperatures and under conditions of a wide range of vibrations. .

A method of manufacturing piezoelements, including plasticization, pressing and sintering synthesized Pb powder (ZrRi) at a temperature of 1200-1300 ° C, mechanical processing (grinding to shape), electroplating of silver electrodes, or methods used is known and is widely used in manufacturing. Vzhigani house and polarization.

The disadvantage of this method of manufacturing piezoelectric elements is low productivity, since the method consists of several separate technological processes, and also requires the mechanics of sanding (grinding) sintered billets.

The closest to the invention in terms of technical complexity is a method of manufacturing a rod piezoelectric transducer, including pressing and sintering.

powder, the connection of electrodes with piezoceramics and polarization 2.

The disadvantage of this method is the low quality of the production of piezoelectric elements.

The aim of the invention is to improve the quality of the production of piezoelectric elements at the expense of ensuring a high density of piezoceramics and strength

10 connections of piezoelectric ceramics with electrodes.

The goal is achieved by placing the powder in the mold between metal electrodes, compressing it with a pressure of 8-12 kgf / mm, heating at a speed of 5-7 s / min to a temperature of 400-500 below the sintering temperature of this powder, being held for 30 -50 min and cooled at a rate of 5-7 ° C / min and at a temperature exceeding the Curie point by 10-50 ° C, polarization is carried out during the cooling process.

In the case of using the powder of the composition Pb (ZrTi) Oj | The ri or copper or nickel electrodes are carried out as follows.

Claims (2)

Before assembly into the mold, metal electrodes are degreased, then assembled in a device that is installed in a vacuum chamber, powder is poured, compressed by pressure of 8.0-12.0 kgf / Mg, vacuum is created, mercury, st. is heated to a temperature of 5–7 C / min, kept for 30–50 min, then cooled at a rate of 5–7 ° C / min. During the cooling process, at a temperature of 10–50 ° C beyond the Curie point, the floor rizuyuschey field, close to the size of the breakdown. Temperature control is carried out by thermocouple. The verification of the process modes showed that a decrease in pressure of less than 7 kgf / mm required an increase in sintering temperature more. An increase in temperature leads to evaporation of lead oxide and a violation of the stoichiometric composition of ceramics. The heating rate of more than 7 C / min does not allow to obtain high-quality,. in composition, piezoceramics due to the uneven heating of all the powder volume. Cooling at a speed of more than 7 s / min leads to the appearance of cracks in the piezoceramics and on the surface of the junction of the electrodes with the ceramics. A decrease in the rate of heating and cooling of less than 3 C / min will lead to an increase in the duration of the process. The removal of pressure at a temperature above 50 s; leads to the appearance of cracks in piezoelectric ceramics. The use of the proposed method of manufacturing piezoelectric elements in comparison with existing methods has the following advantages. The laboriousness is reduced, since the production of a piezoelectric element is carried out by combining the processes of pressing sintering, shaping the billet to connect the electrodes with the piezockers. The density increases due to the change in high pressures of 8–12 kgf / mm, and the piezoelectric module due to the increased density. The strength of the joint between piezoelectric ceramics and copper electrodes is enhanced by the activation of diffusion processes that occur between powder and copper at high temperatures and pressures. The cost is reduced by increasing productivity and eliminating the precious metal, silver. The fundamental difference between the proposed composition and the currently used hot pressing, grinding and electrode deposition is that this method produces pressing, sintering, shaping and joining of piezo ceramics simultaneously. with metal electrodes at temperatures below 400-500 C of known sintering temperature with simultaneous polarization of the piezoelectric elements. Claims The method of making piezoslementov, including pressing and sintering powder, connecting electrodes with piezoceramics and polarization, characterized in that, in order to improve the quality of manufacture of piezoelectric elements by providing high density piezoceramics and electrodes, the powder in the mold is placed between metal electrodes, they are compressed by pressure of 8–12 kG / mm, heated at a rate of 5–7 ° C / min to a temperature of 400–500 Å below the sintering temperature of this powder, upper vayut during 3050 min and cooled at a rate of 5-7 C / min and at a temperature above the Curie point of 10-50 C rizuyut floor during cooling. Sources of information taken into account in the examination 1, Glozman I.A. Piezoceramics. Energy 1967, p. 28-33. 2. USSR author's certificate number 618871, cl. H 04 R 17/00, 1973. (Prototype).