JPH02233566A - Jointing method for ceramic member - Google Patents

Abstract

PURPOSE:To accomplish the title easy, firm jointing by applying, when forms prepared by adding an additive to ceramic powder followed by granulation and forming are to be mutually jointed, the same additive as that used in said granulation on the surfaces to be jointed followed by jointing and sintering. CONSTITUTION:A water-soluble additive (e.g. polyvinyl alcohol) or oil-soluble additive (e.g. polyvinyl butyral) is added to ceramic powder (e.g. alumina powder) followed by granulation and drying. Using the resultant granules, ceramic members 1 and 2 are formed. The same additive as that used in the above granulation is then applied on the surfaces to be jointed of said members 1 and 2. Thence, these surfaces 4 are mutually jointed at normal temperature and pressure followed by sintering, thus accomplishing the objective firm jointing in good workability.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for welding and joining ceramic members to each other at room temperature and pressure.

Previously, it was thought that it was extremely difficult to uniformly and mass-bond ceramic members to each other, but recently, for example, Japanese Patent Laid-Open Nos. 63-225583 and 63-225583,
Inventions such as those shown in Japanese Patent No. 3-225584 and Japanese Patent No. 63-248778 have been developed.

The first invention is a method of joining ceramics having electrical conductivity at high temperatures, heating the joined part with a gas flame, and applying a voltage to the joined part to apply a heating current. , the second invention is a method of joining by filling the joining part of ceramics with a brazing material, irradiating this brazing material with a laser beam, and melting and solidifying the brazing material at that temperature. The invention is a method of joining ceramic members by providing irregularities in the joint portion in advance, fitting the irregularities into each other at the time of joining, and simultaneously performing firing.

Problems to be Solved by the Invention> However, in both the first and second inventions mentioned above, the joints of ceramics are heated to high temperatures by applying a voltage or irradiating them with a laser beam. Since it has to be processed in a vacuum, large equipment is required, mass production is difficult, and costs are high. In addition, in the third invention, it is necessary to provide irregularities in the joining part of the ceramic members in advance, so the workability is poor and it is difficult to mass-produce at a low cost.Furthermore, joining marks are left on the joining part due to the uneven fitting. There was a problem.

The bonding method according to the present invention relates to a completely new technology developed in view of these drawbacks of the conventional technology, and in particular relates to a method for bonding ceramic members that makes it possible to bond ceramic members to each other at room temperature and normal pressure. be. <Means for solving the problem> The method according to the present invention involves molding both ceramic members to be joined using ceramic granules obtained by adding a water-soluble or oil-based additive to ceramic powder and drying and granulating them. Then, apply the same water-soluble or oil-based adhesive as the additive used for granulating the ceramic granules to the joint surfaces of the ceramic members, and further bond the joint surfaces of these ceramic members to each other at room temperature and normal pressure. This is a method for joining ceramic parts, which is characterized by sintering the ceramic parts after joining them. As described above, the method according to the present invention uses ceramic/diamond granules obtained by adding the same water-soluble or oil-based additive to ceramic powder and drying and granulating them as a material for both ceramic members to be joined. Then, the same water-soluble or oil-based adhesive as the additive used for granulating the ceramic granules is applied to the bonding surfaces of the ceramic members, and the bonding surfaces of these ceramic members are then heated to room temperature. Since they were bonded together under normal pressure, the ceramic granules that form these bonding surfaces can be applied later by applying a fusing agent containing the same additives used for granulation to the bonding surfaces of the ceramic members. The adhering adhesive can easily penetrate and melt to moisten this area, thereby making the granules on the joint surfaces of both ceramic members adhere to each other and ensuring that they are fused together. I can do it.

In the method according to the present invention, the ceramic members are fired at a predetermined temperature after they are joined, so that the joint portion of both ceramic members can be formed into the same crystal as the other parts of the ceramic member.

EXAMPLE> An example of the method for joining ceramic members according to the present invention will be specifically explained with reference to the drawings as follows.

In the figure, Fig. 1 is a cross-sectional view showing two joined members and their joint part, Fig. 2 is a cross-sectional view showing the joined members, and Fig. 3 is a fusion agent applied to the joint surface of the joined members. FIG.

First, the composition of the ceramic granules (powder) used in the ceramic member of the present invention will be explained as follows. That is, in carrying out the present invention, first, polyvinyl alcohol (PVA) is added to ceramic powder made of alumina.
, or a water-soluble synthetic lubricant such as polyvinyl methyl ether (PVM) and polyethylene glycol (PEG).
) Alternatively, Ceraminx granules (powder) are produced by adding a water-soluble additive mixed with a water-soluble synthetic lubricant such as polyvinyl pyrrolidone (Pvp) and granulating it by a spray drying granulation method. In the above example, an example was explained in which ceramic granules were granulated using a water-soluble additive, but a binder such as polyvinyl butyral (PVB) and dibutylphthalate (DBP) or dioctylphthalate ( Ceramics are made by granulating by spray drying without adding an oil-based additive made by mixing a plasticizer such as DOP), a dispersant such as oleic acid, and a solvent such as methyl ethyl ketone (MEK), acetone, or toluene. Granules can be produced.

Next, as described above, the granulated granules are filled into a mold and then pressed at low pressure (approximately 100-1000 kg/cJ) to bond the two pieces together as shown in Figures 1 to 3. The ceramic member 1.2 is molded. Next, the water-soluble additive used for granulating the above-mentioned ceramic granules, namely polyvinyl alcohol (PVA)
, or a water-soluble synthetic lubricant such as polyvinyl methyl ether (PVM) and polyethylene glycol (PEG).
) or a water-soluble synthetic lubricant such as polyvinyl pyrrolidone (PVP) and a water-soluble synthetic lubricant such as polyvinyl pyrrolidone (PVP). Apply it to the joint surface of 2. The bonding surfaces of the ceramic members 1 and 2 coated with the adhesive 3 on this birch gradually become wet as the ceramic granules forming this surface are penetrated and fused by the adhesive 3 (the adhesive Approximately 1 after applying 3
In this state, the bonding surfaces of the ceramic members 1 and 2 are brought into close contact with each other, and the molten granules on both bonding surfaces are glued together and fused together. Furthermore, the ceramic members 1 and 2 that were mutually fused to this keyaki were gently transferred to a firing device, and both were heated at the same time to a temperature of 1,300 to 1.
By firing at a high temperature of 500° C., it is possible to obtain a ceramic sintered body in which both ceramic members 1.2 are firmly joined at the joint portion 4 as shown in FIG.

In the above example, a water-soluble additive was used for granulating the ceramic granules, and the same water-soluble adhesive was used for the subsequent fusing agent 3, but in contrast to this method, It is also possible to use an oil-based additive in the initial granulation and then use the same oil-based adhesive as the additive in the adhesive 3, and both can achieve almost the same effect. When a water-soluble additive is used in the granulation of ceramic granules in this way, the fusing agent 3 applied to the joint surface of the ceramic part 1.2 is also the same as the water-soluble additive used for granulation. It has been found that only by using a water-soluble welding agent 3 can the two ceramic parts 1.2 be welded together.

In the above example, alumina was used as the ceramic powder, but other materials such as zirconia and milica were used. Oxide ceramic powders such as alumina/silica, cerium oxide, magnesia, titania, mullite, subinel, cordierite, etc., and silicon nitride. Aluminum nitride, boron nitride, titanium nitride, silicon carbide, boron carbide, tungsten carbide. Non-oxide ceramics such as Sialon can also be used.

In the above examples, PVA, PV), PEG, PVP, etc. were used as water-soluble additives or water-soluble adhesives, but other water-soluble additives of this type include starch dextrin, alginic acid, etc. , gum arabic, gelatin,
Casein, methyl cellulose (MC), calcium lignin sulfonate, glycerin, polyacrylic acid amide 1 sodium polyacrylate 1 vinyl pyrrolidone-vinyl acetate copolymer. Tannic acid and the like can also be used.

In the above embodiments, PVB, DBP, DOP, )III! are used as oil additives or oil adhesives. J-acetone, toluol, etc. were used, but other oil-based additives of this type include Schlafuku, wax emulsion, ceresin,
Ethyl cellulose (EC), acetyl cellulose. Ester gum, polyvinyl acetate, chroman resin, phenol resin, ethyl silicate, etc. can be used. <Effects of the Invention> Since the method for joining ceramic members according to the present invention has the above-described structure and operation, it is possible to reliably perform the joining of ceramic members at room temperature and pressure, which has been considered extremely difficult in the past. Therefore, it is possible to completely eliminate the need for large equipment as in the past, and it is extremely workable and can be mass-produced at low cost.Furthermore, it does not leave any traces of joining at the joint. It has the following characteristics.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing two joined members and their joint parts, Figure 2 is a cross-sectional view showing the joined members, and Figure 3 is a diagram showing the application of a fusing agent to the joint surfaces of the joined members. FIG. 1 and 2 are ceramic members, 3 is a fusion agent, and 4 is a joint portion.

Claims (1)

[Claims] A water-soluble or oil-based additive is added to the ceramic powder. Ceramic granules that have been dried and granulated are used to mold both ceramic members to be joined, and the same water-soluble additive as used for granulating the ceramic granules is added. The ceramic member is characterized in that an adhesive or oil-based adhesive is applied to the bonding surfaces of the ceramic members, and the bonding surfaces of the ceramic members are bonded to each other at room temperature and normal pressure, and then the ceramic members are sintered. How to join parts.