JPS60180959A - Manufacturing method of PLΖT transparent sintered body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula (Pb, -xLaX) (Zr, , Ti
y), X 0゜ (however, O<x≦0.12, 0
<y<1.0) (abbreviated as P, L, Z, and T) The transparent sintered bodies of P, L, Z, and T are piezoelectric. As a method for manufacturing conventional sintered bodies of P, L, Z, and T, which have the following properties, (1)
A method in which oxide powders of component elements are mixed, calcined, and then hot pressed.

(2) A method in which component element ions in an aqueous solution are precipitated as hydroxides, which are then dried, calcined, and then hot pressed.

(5) A method in which alkoxides of component element ions are hydrolyzed and co-precipitated, the resulting precipitate is calcined, and then hot pressed! :i is known.

However, method (1) requires hot pressing at high temperatures due to the large powder particle size, and method (2), which produces a sintered body with lower transparency, is better than method (1). Although it is a fine powder and has good sinterability, there is a difference in the solubility of the hydroxides of the component element ions in water, which makes it difficult to co-precipitate them in the desired ratio. In addition, impurities present in aqueous solutions are also troublesome, and alkoxides generally have strong hygroscopicity, making them inconvenient to handle, lacking mass productivity, and being economically disadvantageous. be.

The present invention was made in order to eliminate the drawbacks of the conventional method, and its purpose is to produce a P, L, Z, T sintered body 1 j that is free from contamination with impurities during production, has a high J'- value, and has excellent transparency. The goal is to provide a method for manufacturing items into mementos.

By co-precipitating these component ions as oxalate in ethanol, a homogeneous and highly pure fine powder was obtained. When the obtained oxide powder is hot pressed,
We found that P, L, Z, T sintered bodies with extremely high translucency can be obtained compared to conventional p, l+, Z, T sintered bodies, and based on this knowledge, we developed this book (however, 0 < x≦0.12
, 0 < y < 1.0), ethanol was added to a mixed aqueous solution of nitrates of Pb, LatZr and Ti, and a solution of oxalic acid dissolved in ethanol was added dropwise to this solution. A method for producing transparent sintered bodies of P, L, Z, and T is characterized by: producing a precipitate, refining and thermally decomposing the precipitate, and molding and hot pressing the same.

and produce oxalate. These chlorides have a similar effect, but when chlorides are used, lead ions and chlorine ions create insoluble lead chloride, and chloride ions mix as impurities and inhibit sintering. It needs to be a nitrate.

Pb, La so as to have the composition shown in the above general formula.

Zr and Ti nitrates are mixed to form an aqueous solution. this'
So, ← to obtain the desired composition K is Pb.

Director L, Zr and T1 respectively, 10.50.20.
It is desirable to add it in excess of 40 mol%.

The concentration of this mixed aqueous solution is 500- as P, L, Z, and T.
The concentration is preferably about 0.05 mol.

Add ethanol to this mixed aqueous solution. It is preferable to use a large amount of ethanol, but since too much ethanol may cause cloudiness, it is desirable to add ethanol little by little. This is because the oxalates of the P, L, Z, and T components are completely insoluble in ethanol, so these component ions coexist as oxalates in ethanol. This is because when allowed to settle, a uniform and highly pure fine particle powder is obtained.

The amount of oxalic acid added is equivalent to the mixed component ion, the ethanol used is the final ethanol, and when the oxalic acid ethanol solution is added dropwise little by little, a white precipitate is formed.

The particle size of this precipitate is highly dependent on the reaction temperature. That is, since the lower the reaction temperature, the finer the particles, it is desirable to carry out the reaction at a temperature below room temperature.

The resulting precipitate is a collection of fine particles.
- If this is sintered as it is, there will be no adverse effect on sintering, so wash thoroughly with ethanol to remove 1. -11 is preferable, which removes most of the water of crystallization and disrupts the crystal structure.

After drying, this is pulverized and thermally decomposed at 800 to 1000C. It is desirable that this thermal decomposition temperature is low, but if the temperature is too low and the thermal decomposition is incomplete, the sintered body will be easily damaged, and if the temperature is too high, the growth of particles will be reduced. The above-mentioned temperature range is preferable since this will cause distortion in the molded body, so it is preferable to use a low pressure that does not cause the molded body to collapse.0 Therefore, the above-mentioned temperature range is preferable. .

The obtained molded body was put on a rubber press (#) 1.6 to
It is subjected to secondary molding at a pressure of n/cm2 or higher, and then hot pressed in a die, for example an alumina die. This hot press is carried out at 1100 to 1200°C, and by this method, a sintered body with extremely high purity and excellent translucency can be obtained without containing any impurities.Example PbL92 La0008 zro, as 'I'io
, as 05 Production Titanium tetrachloride is precipitated as hydroxide with aqueous ammonia, and the precipitated titanium hydroxide is poured into ice-
Using water Zr0(NO,)2-2H20, P, L,
Z, T tD The number of moles was 0.05 moj, and the amount of solution after dissolving the starting material in water was 500. In addition, in order to approximate the composition of the sintered body to be obtained, Pb, La,
Zr, Ti 10.50.20.40 mol% respectively
Added in excess. After adding 250% of ethanol to this aqueous solution, 50% of each component and the equivalent amount of dichloromethane ions were added.
A solution of 0-0 dissolved in ethanol-λ was heated at 5° C. for 15 minutes: The solution was kept in a constant temperature bath at 5° C., the same as the reaction temperature, all day and night, and then filtered. The precipitate was washed 3 times with ethanol and
After drying at ℃, the pyrolyzed product was pyrolyzed in air at 800℃ for 2 hours, and the resulting pyrolyzate was first formed into a disk shape with a diameter of 12 pieces and a thickness of 5 pieces at a pressure of 200 Ky/m2. , 1.6t
Secondary molding was performed under hydrostatic pressure of On/cIL2. Next, the relationship between this length and transmittance was as shown in FIG.

The person in the figure was obtained in this example.・21! Transmittance in a sintered body of @thickness, B is Haertling (J, A
m, Oeram.

Soc, 54, 303 (1971).

As this drawing shows, the substrate obtained by the method of the present invention has the advantage of excellent transmittance for each wavelength of incident light.

(1) Stable P, L, Z, and T powders can be obtained quickly and easily.

(2) The resulting powder is uniform and highly pure.
5) Shows high translucency. As shown in FIG.

(4) It can be manufactured at low cost and is suitable for mass production.

(5) Exhibits high dielectric constant. (The dielectric constant at room temperature is 4500 at 100kHz).

A is the turtle in the sintered body (thickness 2+as) of the present invention (Example), B is the conventional Haertling (J,
Am, Geram.

Soc, 54.303 (1971) Sintered body (thickness 1fi) K 0 Patent applicant Director of Inorganic Materials Sales Office, Science and Technology Agency; Sakaki Goto I:

Claims (1)

[Claims] 1. General formula (pb 1-xLax) (Zr 1-yT
'y), -'Os (where 0<x≦Sail12, 0
<y<1.0) to the proportion that results in the composition shown,
Pb. Ethanol is added to a mixed aqueous solution of nitrates of La, Zr, and Ti, and a solution of oxalic acid dissolved in ethanol is added dropwise to this solution to form a precipitate. This precipitate is purified and thermally decomposed, and then molded and molded. (Pb, -xLax) (Zr1.'riy), characterized by hot pressing;
-Production method of Xo5a light sintered body.