JPS6096583A - Ceramic member for bonding and bonding method - 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 [Field of Application of the Invention] The present invention relates to a joining ceramic member and a joining method thereof, and more particularly to a joining ceramic member using an active metal and a joining method thereof.

[Prior art]

In recent years, silicon nitride, silicon carbide,
So-called new ceramics, such as non-oxide ceramics such as Sialon, aluminum oxide, and zirconium oxide, are rapidly attracting attention, and much research and development is being carried out. These ceramics have many uses as gas turbine rotors, diesel engine cylinders, and other high-temperature machine parts, but all of them have strict requirements for shape and dimensional accuracy, making it difficult to mold and manufacture them as a single piece from the beginning. Often.

For this purpose, it is necessary to bond partial products together to create complex shapes, and it is desired to develop a method for firmly bonding ceramics to each other or ceramics and metals.

Conventionally, a so-called hot press bonding method in which an adhesive is interposed between ceramics and pressure is applied at high temperature has been commonly used as a method for bonding ceramics, but it is difficult to bond members with complex irregular shapes.

Additionally, multiple types of inorganic adhesives are being developed.
Various products are manufactured and sold in Japan as well. However, many of these inorganic adhesives are usually made of silica, alumina, or zirconia as their main raw materials, and although they have heat resistance, they have the disadvantage of being weak against forces that would cause the bonded surface to peel off. .

Furthermore, brazing is a bonding method that has higher bonding strength than such inorganic adhesives. By the way, the conditions for brazing ceramics are that the objects to be bonded are wetted by the brazing material and that the objects to be bonded and the brazing material are tightly bonded. At present, sufficient brazing strength cannot always be obtained due to poor affinity (so-called wettability) and low reactivity with various substances.

The active metal method is a method for improving the wettability between ceramics and brazing filler metals to achieve good bonding.

This method involves inserting Ti, Zr, etc., which are very active, and Ni, CulAg, which are alloys with a relatively low melting point, between a ceramic member and the other member so that they have a eutectic composition, and then This is a method of joining by one heating operation in a medium or inert gas.

This activated gold M method completes bonding in one heating operation and is convenient because it can be used for single crystals such as sapphire and most other ceramics, but Ti, Zr, etc. are extremely active. However, they are extremely susceptible to oxidation, and there is a problem in that they must be operated in a vacuum or in an inert gas atmosphere to prevent them from oxidizing during the bonding process.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to provide a joining ceramic member and a joining method thereof that can firmly join ceramics using an active metal even in the atmosphere. It's about doing.

[Structure of the invention]

In order to achieve this object, the present invention covers the active metal layer formed on the surface to be bonded on the ceramic part side with an inactive metal layer, and prevents the active metal from bonding with oxygen. This is what I did.

The present invention will be explained in detail below with reference to the drawings.

1 to 3 are cross-sectional views showing embodiments of the joining ceramic member of the present invention.

The ceramic member for bonding of the present invention is shown in FIGS. 1 to 3.
As shown in the figure, an active metal layer 2 is provided on the surface of the ceramic member 1 to be joined, and an inactive metal layer 3 is further formed to cover this.

Specifically, the active metal of the active metal layer 2 provided on the surface to be bonded includes Ti, ZrlHf%Ta, Nb, and Ce%.
La, Y, etc., and especially Ti, Zr and Hf.
Va group metals, especially Ti and Zr, are preferred.

There are no particular limitations on the method for forming the active metal layer 2, and methods such as sputter deposition or attaching an active metal foil can be suitably employed. Especially ceramic parts
If the material is porous, vapor deposition is preferred. When such an active metal layer 2 is formed by sputter deposition, it is preferably formed using a layer of 0.5 to 20 .mu.m, and when a foil is used, a foil of 10 to 100 .mu.m.

The inactive metal layer 3 covering the active metal layer 2 is made of Au,
Examples include a layer of gold R such as Pt, Ag, Pd%Rh, or an alloy of these noble metals, or a layer of an alloy having a brazing material composition. As the noble metal, Ag is preferable from the viewpoint of cost, and as the metal alloy, an Ag-Cu alloy having a brazing material composition is preferable.

There are no particular limitations on the method for forming the inactive metal layer 3, and vapor deposition such as sputtering MM, pressure bonding of an inactive metal foil, plating, thermal spraying, back treatment, etc. can be employed. Since the inactive metal layer 3 is for preventing oxidation of the active metal,
An active metal layer 2 is formed overlyingly. Therefore, the first
As shown in the figure, the entire ceramic member 1 is coated with a noble metal such as Ag along with the activated gold JIi layer 2, and as shown in Figure 2, a layer of a noble metal such as Ag is provided only on the active metal layer 2, and the other parts are coated with a noble metal such as Ag. is Al or stainless steel, etc. f) 163'
It is also possible to provide a coating. Also, inert metal IN
3 and the ceramic member 1 are in close contact with each other, it is possible to cover only the active metal layer 2 as shown in FIG. If the structure shown in FIGS. 2 and 3 is used, the amount of Ag used is smaller than that shown in FIG. 1, and the cost can be reduced.

The thickness of the inactive metal layer 30 varies depending on the type of inactive metal, the formation method, etc., but for example, when forming an Ag layer by vapor deposition, etc., the layer thickness is 10 to 40 μm, and the layer thickness is 10 to 40 μm. When forming, it is preferable to use a foil of 30 to 200/a.

The inactive metal layer 3 is formed by forming the active metal layer 2 on the ceramic member 1 in order to prevent oxidation of the active metal as much as possible.
It is preferable to form the active metal layer 3 immediately, and when the inactive metal layer 3 is formed by a pack process or the like, it is preferable to degas the space between the active metal layer 2 and the inactive metal layer 3 using a vacuum pump or the like. Furthermore, an appropriate stress relaxation layer or a deoxidizing agent such as Ti, Mg, Ca, etc. may be interposed between the inactive metal layer 3 and the active metal layer 2.

In addition to these, r i /Ag or Ti/Ag-C
It is also possible to adopt a method in which a cladding material of an active metal such as a u-alloy and an inactive metal is formed and then bonded to the surface of the ceramic member to be joined.

Next, the joining method of the present invention will be explained with reference to FIGS. 4 to 6.

The joining method of the present invention is a method of joining the ceramic members for joining of the present invention as described above, after forming an active metal layer and an inactive metal layer covering the active metal layer on the surfaces to be joined. , a first method in which this is brought into contact with a mating member via a bonding material and heated and bonded; and a second method in which the active metal layer is coated with a layer of a brazing material composition and then brought into contact with a mating member and heated and bonded. A second method is included.

A first method of bonding of the present invention is to bring ceramic members 1 on which an active metal layer 2 and an inactive metal layer 3 have been formed into contact with each other via a bonding material 4 and heat them, as shown in FIG. 4, for example. The bonding material 4 is melted and bonded. Bonding material 4
Examples include metals or alloys of components that are fused with the brazing filler metal or non-active metal to form the brazing filler metal composition. The filler metal is a noble metal filler, especially in the atmosphere (or if necessary, a simple A
rshield) Usable self-flux type Ag
Wax and the like are preferred. When the inactive metal is Ag, Cu or a Cu alloy is preferable as the material that is fused with the inactive metal to form the brazing material composition.

Further, in a second joining method of the present invention, as shown in FIG. 5, ceramic members 1 each having an active metal layer 2 coated with a layer 5 having a brazing material composition are brought into contact with each other, and heated to coat the layer 5 having a brazing material composition. It is joined by melting.

In this method, it is not necessary to use a bonding material such as a brazing filler metal, but there is no problem in joining with the intervening material.

4 and 5 both show the case where ceramic members are joined together by the method of the present invention. Therefore, both members are provided with an active metal layer and a layer covering this. In the invention, it is also possible to join the ceramic member to another mating member such as a metal member. When the other member is a metal member, the present invention can be applied to the metal member as it is without any roughening treatment.

In the present invention, as a heating method after the ceramic member is brought into contact with the other member, any heating method that can be normally employed can be employed, but high frequency induction heating is most preferable.

The method of the present invention is particularly effective for bonding large-sized ceramic plates; however, in this case, for example, as shown in FIG. The ceramic member 1 on which the layer 5 has been formed is brought into contact with a mating member 14 made of metal or the like, and the iron core 15 having the high frequency coil 12 is heated from the side opposite to the joining surface to perform the joining. The iron core 15 has a disk shape, and a circular convex portion 16 is provided on one of the central portions, and the coil 12 is wound concentrically with the convex portion 16. To join the ceramic member 1 and the other member 14, first, the two members are brought into contact with each other, and then the iron core 15 is arranged so that its convex portion 16 is in contact with the ceramic member 1 as shown in the figure. Then, electricity is applied to the coil 12 of the iron core 15 to heat and melt the layer 5 of the brazing filler metal composition to join them. In this case, in order to more reliably prevent oxidation of the active metal, it is preferable to shield with an inert gas such as argon gas G using the nozzle 13 or the like.

Although Fig. 6 shows a case in which a ceramic member is used in which the active metal layer is coated with a layer having a brazing filler metal composition, a ceramic member in which the active metal layer is coated with a metal layer other than the brazing material may also be used. By interposing a bonding material such as a brazing material between the ceramic member and the mating member, the bonding can be easily performed by a similar method.

[Embodiments of the invention]

The present invention will be explained in more detail with reference to examples below.
The present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1 Commercially available zirconia plate (composition: ZrO, -3mo#%Y
, 03. Size: 30mX 30mgX 10FJ
) was joined to J) CrMo steel plate by the method of the present invention.

After finishing the above zirconia plate to a surface roughness of IS, it was cleaned, and a 5 μm thick Ti plate was applied to the bonding surface (30+usX30 order surface).
A layer was deposited. After that, 10% of the Ti layer was covered with
A μm thick Ag layer was deposited. A silver solder sheet with a thickness of 0.1 dew was interposed between the joint surface of the zirconia plate on which the 11 layers and the Ag layer were formed in this way and the CrMo steel plate,
The two were bonded by high-frequency induction heating to 900° C. while shielding with Ar in the atmosphere using the method shown in FIG.

Ita silver solder for Nao is BAg4 (Ag 30ωt, % C
u - Tightly joined.

Example 2 A Ti layer with a thickness of 5 μm was deposited on the bonding surface of the same zirconia plate as in Example 1, and a silver solder sheet having the BAg4 composition described above was further pressure-bonded onto the Ti layer.

When this zirconia plate and a CrMo steel plate were joined by the same method as in Example 1, they were extremely firmly joined.

Comparative Example I The bonding process was carried out in the same manner as in Example 1 except that the Ag layer was not coated on the Ti layer, but the zirconia plate and the Cr
It was not joined to the Mo steel plate.

Comparative example 2 The bonding process was performed in the same manner as in 2.

As a result, the zirconia plate and the CrMo steel plate were joined, but the strength was much lower than in Example 2.

〔Effect of the invention〕

As detailed above, the present invention involves forming an active metal layer and an inactive metal layer covering the active metal layer on a ceramic member. It is designed to preserve the active metal's life and prevent the oxidation of this active metal, making it possible to easily bond extremely strong ceramics in the atmosphere without strict atmosphere control. Therefore, it is possible to join very large members to each other, and it is also possible to join them outdoors, and the workability of joining is extremely good.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views showing embodiments of the ceramic member for bonding of the present invention; FIGS. 4 and 5 are cross-sectional views illustrating a method of bonding ceramic members together according to the present invention; and FIG. FIG. 2 is a cross-sectional view illustrating a method of joining a plate-shaped ceramic to a mating member according to the present invention. DESCRIPTION OF SYMBOLS 1... Ceramic member, 2... Active metal layer, 3...
... Inactive metal layer, 4... Bonding material, 5... Brazing material composition layer, 12... High frequency coil, 13... Nozzle, 14... Counterpart member. Agent Patent Attorney Tsuyoshi Shigeno Figure 1 Figure 2 Figure 3 Figure 4 Figure 6

Claims (1)

[Scope of Claims] (2) A ceramic member for bonding comprising a layer of an active metal and an inactive metal layer covering the active metal layer on a surface to be bonded of the ceramic member. (2) The inactive metal is , a noble metal or an alloy of noble metals. (3) A patent characterized in that the inactive metal is an alloy having a brazing material composition. A ceramic member for joining according to claim 1. (4) In a method of joining a ceramic member to a mating member, a layer of activated gold scraps is added to a surface of the ceramic member to be joined, and an inactive metal layer covering the active metal layer is provided. A method for joining ceramic members, characterized in that after forming a metal layer, the ceramic member is brought into contact with a mating member via a joining material, and the joining member is melted and joined by heating. The bonding method according to claim 4, wherein the inactive metal is a noble metal or an alloy of noble metals, and the bonding material is a brazing material. (6) The inactive metal is a noble metal or a noble metal. 5. The bonding method according to claim 4, wherein the bonding material is a metal or alloy having a component that fuses with the noble metal or alloy of the noble metal to form a brazing filler metal composition. (7) In the method of joining a ceramic member to a mating member, after forming an active metal layer and a layer of a brazing material composition covering the active metal layer on the surface to be joined of the ceramic member, the ceramic member is brought into contact with the mating member. A method for joining ceramic members, characterized in that the layers of the brazing filler metal composition are melted and joined by heating.