JPS61242964A - Joined body and joining method of oxide base ceramic and metal - 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 A) Industrial Application Field The present invention is applied to oxide-based ceramics and clays mainly composed of oxides such as zirconia, alumina, silica, and magnesia, and metals and alloys such as copper, nickel, and stainless steel. (herein referred to as metal including alloys) and a joining method.

口）Conventional technology Ceramics have excellent heat resistance, corrosion resistance, and wear resistance, but when trying to utilize them effectively, the difficulty is that ceramics are brittle, that is, vulnerable to shock, and when used as structural materials. It is desirable to use it as a bonded body with a metal that has excellent toughness. This method can greatly expand the applications of ceramics.

Various studies have been conducted on bonding ceramics and metals. That is, there are methods such as those using organic or inorganic adhesives, mechanical joining using K such as shrink fitting, etc., and recently excellent adhesives have been developed and are being evaluated accordingly. However, chemical reactions and
The most excellent bonding method is the so-called metallization method, which uses the diffusion-penetration effect.

This metallization method is roughly divided into the following three types.

■It is also called the high melting point metal method, and Mo, M.

-Mn r W r W-Mn or kaolin etc. are added to these, mixed with a binder and heated to 1600 in humidified hydrogen.
A method of heating the material to around ℃ to infiltrate Mo+W, applying N1 holes, holes, etc., and then locking it with the joining metal. The bonding mechanism is that Mn melts into the ceramic to form MnO, and Mo is slightly oxidized and penetrates into the glass phase of the ceramic phase and the N1 plating phase to bond.

■ A method in which a precious metal foil such as Au, Pt, or Pd, which is easily deformed plastically, is sandwiched between ceramics and metal and crimped. In this case, it is said that even stronger bonding can be achieved by using hot gelless, hot isostatic press (hot isostatic press), or the like.

■ A method of joining ceramics and metal by interposing an intermediate insert material that easily causes a chemical reaction. The insert materials are generally oxidized steel, sulfided steel,
Known materials include lanthanum chromate, carbonate steel, titanate steel, and K to which ceramic, camphor powder, kaolin, etc. are added. When joining, the above insert material is inserted between the ceramic and the metal, heated in an oxidizing atmosphere, permeated into the ceramic, and then joined in a reducing atmosphere. There is a method in which copper is simultaneously infiltrated into the ceramic phase in an oxidizing atmosphere, as in the above method, and on the other hand, copper is precipitated by thermal decomposition and the metal is bonded to the deposited copper. That is, mechanically, on the one hand, the ceramic, the wood, and the intermediate insert material are fused and penetrated, and on the other hand, the intermediate insert material is reduced and bonded to the metal to be joined.

Regarding the above three methods, method ■ requires a lot of man-hours;
In the method (2), the precious metal itself is expensive, and the method (2), that is, the method using an insert material, is currently attracting the most attention.

C) Problems to be Solved by the Invention Various examples have been reported in which oxide-based ceramics such as alumina-based, magnesia-based, and silica-based ceramics have been successfully joined by methods using insert materials. However, Zr
Regarding zirconia ceramics containing 90% or more of O has not yet been reached.

The object of the present invention is to provide not only these general oxide ceramics but also a bonded body of zirconia ceramics and metal, and a method for bonding the same.

2) Means to solve the problem The present inventors focused on the stability of zirconia, and as a result of considering the phase formed by strong reduction, the inventors found that at least Ca
15-80 Chi, Si and U of la! Or 2 types
A thin plate or powder of an alloy containing 0 to 85% or a binder added to the powder is inserted as an insert material between the oxide ceramics to be joined and the metal, and heated at 900°C in a non-oxidizing atmosphere. The heat treatment below the melting point of the metals to be joined allows oxide ceramics and metals, including zirconia ceramics, which conventionally have been impossible to join, to the constituent elements of the insert material, oxide ceramics, and metals. We succeeded in obtaining a zygote that is integrated through the genus containing the constituent elements.

e) Function Zirconia ceramics are chemically stable and have a high melting point, so it is difficult for copper oxide, copper sulfide, etc. to penetrate compared to alumina ceramics and glass, so a diffusion layer does not grow and oxidation reduction occurs. The bond will separate. However, in the present invention, the ionic bonded zirconia is reduced using calcium, which is a strong reducing agent, to form a Zr metal bond or a structure similar to this directly on the ceramic surface, and the compound of this and the insert material forms a multi-metal bond. It is expected that the two will be joined together. Rare earth elements such as CarBerSr*Yr can be considered as elements that can effectively reduce the surface of zirconia ceramics, but there are difficulties in handling them other than Ca.

Purchasing antioxidant measures may be effective.

In order to reduce zirconia, a temperature of 900°C or higher is required for the diffusion of the generated zirconium and metal, and if the insert material melts before this joining reaction occurs, a uniform bond can be obtained due to wettability. Therefore, the melting point of the insert material must be 900°C or higher. The melting point of Ca is approximately 800°C, but it is necessary to alloy it to raise the melting point to 900°C or higher.
A suitable alloy may be an alloy having a composition in which one type of Al or 2wI is appropriately added to 8 in consideration of reducing performance.

Next, the reason for limiting the Ca content will be described. Ca content is 1st
If the Ca content is less than 80%, a sufficient reduction reaction cannot be obtained, and if it exceeds 80%, the melting point will be 900° C. or less, making it impossible to achieve good bonding. In the present invention, even if elements other than the above-mentioned Ca, Sl, and AA are contained, as long as Ca has a strong reducing power and a melting point of 900°C or higher, the presence of other elements will not act as a barrier. Conceivable.

The heat treatment temperature is required to be 900° C. or higher, as mentioned above, in order to reduce the zirconia and also to diffuse the produced zirconium and metal.

The upper limit was set to be below the melting point of the metals to be joined.

It is important that the heating atmosphere be a dry hydrogen atmosphere, an inert gas atmosphere, a vacuum, or other atmosphere in which Ca in the insert material is not consumed by oxidation, or a non-oxidizing atmosphere.

The present invention also considers applying a slight pressure to the bonded body during heat treatment, which contributes to improving the bonding strength.

Example 1 The present invention will be explained based on the following example.
Grind into 50 mesh or less and add isopropyl alcohol to this powder.1. -e- It was made into a strip shape. Then, this pasty Ca-Si alloy was mixed with 90% ZrO.
Zirconia ceramic of 2 or more, Cu and Cu (thickness 0.4
wm) Apply between the boards at a rate of 50 cape/art” and 10
The bonding was carried out at 50° C. for 20 minutes in a hydrogen atmosphere.

Table 1 also shows the results of a tensile test performed on a steel bar of diameter 10 with silver brazing on the surface of the Cu plate of this joined body. sample&
Both 1 and 2 are strongly connected and each has a rating of 7.0 Yuichi!
, 7.2 shows the bonding strength of Sea 2.

As a comparative example, welding was attempted using a Ca-Si alloy containing 10% Ca as shown in Sample A3 in Table 1 under the same conditions as above, but no joined body was obtained. In addition, CuO (sample A4), which has been known as an insert material,
Mix 150 mesh powder of CuS (sample flat 5) and alumina powder, apply to the surface of zirconia ceramic of 90'16 Z ro 2 or more, and heat to 1250°C in the atmosphere.
, held for 30 minutes, and then a Cu plate (4 m thick) was placed on the coated surface.
) were stacked and held at 1000° C. for 20 minutes in a hydrogen atmosphere to attempt bonding, but a multi-bonded body could not be obtained.

[Example 2] The Ca-8 pentalloy containing 501Ca of sample plate 6 in Table 1 was ground to 150 pieces and made into a single stroke shape with the addition of isopropyl alcohol. This Ca-Si alloy in the form of a strip was applied between the alumina ceramics and the Nl plate (thickness 4 wr) at a ratio of 70 to 2, and a pressure of 201"76 rtt" was applied at 1200°C in a hydrogen atmosphere. The mixture was heated and held for 30 minutes.

After cooling, a tensile test similar to Example 1 was conducted, and the results were as follows:
The bonding strength was 7.0 kg/1m''.

In the present invention, it may be possible to obtain a good bond by applying a slight pressure during bonding as described above.

Ca-Al, Ca-8k-A of samples S7 and 8 in Table 1
1 alloy was ground into 150 meshes, and isopropyl alcohol was added to form a paste. This paste-like Ca-A1 alloy and Ca-8t-Al alloy were
50 m1 between zirconia alumina ceramics with rO□50% and AA20.50% and Cu plate (thickness 4□)
Coated to a thickness of 7 cm and heated at 1050°C in an argon atmosphere.
As in Example 2, the mixture was heated and held for 20 minutes under a pressure of 2097 cm2. Thereafter, a tensile test was conducted in the same manner as in Example 1, and as a result, joint strengths of 7.4 and 8.0 kg7m2 were obtained, respectively, as shown in the first test.

Further, CuS f, which is a conventional insert material, was used as an insert material to obtain a bonded body according to a conventional method (sample plate 9).

The bonding strength at this time is 6. The bonding strength according to the present invention is superior in Oky/-.

g) As described in detail, according to the present invention, zirconia ceramic, which has conventionally been impossible to bond with insert materials,
It enables the joining of oxide-based ceramics, including metals, and expands the applications of ceramics.

Claims (1)

[Claims] 1. An insert material in which the oxide ceramic and the metal to be bonded contain at least 15 to 80% Ca and 20 to 85% of one or two of Si and Al by weight. A bonded body of an oxide ceramic and a metal, characterized in that the constituent elements are integrated through a layer containing the constituent elements of the oxide ceramic and the constituent elements of the metal to be bonded. 2. An insert material containing at least 15 to 80% Ca and 20 to 85% of one or both of Si and Al is placed between the oxide ceramic and the metal to be joined in a non-oxidizing atmosphere. A method for joining oxide-based ceramics, characterized in that heat treatment is performed at a temperature of 900° C. or higher and lower than the melting point of the metals to be joined. 3. The joined body of oxide ceramic and metal according to claim 1, wherein the oxide ceramic is a ZrO_2 ceramic containing 90% or more of ZrO_2. 4. Oxide ceramics are ZrO_290
% or more of ZrO_2-based ceramics. 3. The method of joining oxide-based ceramics and metal according to claim 2, wherein