JPS6090879A - Ceramic and metal 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 The present invention relates to a method for joining ceramics and metals, and particularly to a method that can prevent ceramics from cracking and join them to metals.

Conventionally, as methods for joining ceramics and metals, (1) an adhesive method, (2) a metallizing method, and (3) a thermal spraying method are known, but each has the following drawbacks.

(1) The adhesive method is the simplest method, but has low adhesive strength at high temperatures.

(2) The metallizing method involves metallizing metal powder such as M□, Mo-Mn, etc. on ceramic, applying N1 plating on top of it, and then joining it to the metal by brazing. Some types have drawbacks that make them difficult to apply.

(3) Thermal spraying melts ceramic powder and sprays it onto metal to bond it, but it has the drawbacks of low bonding strength and the ceramic becoming porous.

As described above, the conventional method has drawbacks such as low bonding strength and restrictions on the ceramic material that can be used.

The present invention was made to eliminate such drawbacks.
81sN4. In the method of joining metal to 810 series ceramic, one of N1, an N1 alloy containing 50% or more of N1, Ou, an Ou alloy containing 50% or more of O, is added to the ceramic as an ion beam as an insert material. After closely fixing them by rating or thermal spraying, heat reaction acceleration treatment is performed to firmly bond them metallurgically, and then the insert material surface and the metal are bonded using a brazing filler metal whose melting point is lower than that of the insert material. The present invention relates to a method for joining ceramic and metal, which is characterized by brazing.

According to the method of the present invention, it is extremely effective in bonding ceramic and metal well and in preventing cracking of ceramic, which is always a problem in bonding ceramics.

The present invention can be applied to gas turbine parts, vehicle parts, and various other items, such as welding of flat lap joints between ceramic and metal, sleeve joint welding, ceramic welding to the inner and outer surfaces of metal inner cylinders, and other complex shapes. Applicable to joining.

FIGS. 1(A) to 1(C) are diagrams showing an embodiment of the method of the present invention in order of steps.

In the figure, 1 is Si3N, SiO-based ceramic, 2 is a joining metal, and 5 is N1 or an N1 alloy containing 50 or more units of N1 (e.g., Ni-0r, Ni-Ou
, N1-P.

N1-B, Ni-0r-B, etc.) or Ou or Ou
Ou alloy containing 504 or more (for example, ou-p
, 0u-Ni.

0u-At, Nu-Zn, 0u-8i, etc.) +
7) f 7f-) material, 4 is a brazing material whose melting point is lower than that of the insert material (solder, At wax, Ag wax, au
wax, N1 wax, etc.).

First, in FIG. 1(A), an insert metal 5 is ion-grayed or thermally sprayed onto a ceramic 1 to form a subassembly. Next, in FIG. 1(B), the assembly is subjected to heating reaction acceleration treatment, and then, in FIG. 1(0), it is brazed with the joining metal M2 and the brazing material 4.

At that time, the ion grating shown in FIG. 1(A) is produced by evaporating the constituent elements in one crucible when the insert material 5 is a single metal of N1 or Cu, and in the case of an N1 metal or an O alloy, each constituent element is evaporated in a separate crucible. It is carried out under known ion blating construction conditions and is tightly fixed onto the ceramic 1. On the other hand, in the case of thermal spraying, plasma spraying etc. are used.
At that time, the insert material 5 is sprayed in a non-oxidizing atmosphere to tightly fix it on the ceramic 1.

The heating reaction acceleration treatment shown in Fig. 1 (B) is performed to increase the bonding strength between the insert material 5 and the ceramic 1, which have been ion-blated or thermally sprayed. (melting point) for at least 5 minutes in an inert gas or vacuum. In addition, hot isostatic pressure treatment (hereinafter referred to as H-P treatment) can also be performed,
In that case, at the above temperature and time, the gas pressure of Ar etc. CL 0
Load more than 1 kg/wm.

In addition, setting the temperature to 15 or more of the melting point of the insert material is
This is because if it is less than this, the bonding reaction between the insert material and the ceramic will be extremely slow, requiring a long treatment time, which is not industrially preferable. The upper limit is set below the melting point of the insert material to prevent it from flowing out when it melts.

The reason why the treatment time is set to 5 minutes or more is because if the treatment time is 5 minutes or less, the bonding between the insert material and the ceramic is similarly insufficient.

Next, as shown in Fig. 1 (0), the insert material 3 is brazed.
The insert material and the joining metal 2 are brazed using a brazing filler metal 4 having a melting point lower than that of . The reason why the low melting point brazing filler metal (4) is used is to reduce the thermal stress generated due to the difference in thermal expansion coefficient between the ceramic 1 and the joining metal 2 during brazing, and to prevent the ceramic 1 from cracking.

The effects 'f' of the method of the present invention detailed above are summarized as follows.

(Il 811N4, EIIO and metal have different material structures (1llt, N4. B10 is a covalent gold I
JJ4 is a metal bond), and its bonding is extremely difficult.

The present invention uses Nl and Nj gold alloys Ou as insert materials.
, By using Ou alloy, S'1N4s8
10 and this insert material shows excellent metallurgical bonding properties,
A good joint can be obtained.

That is, free 81 exists in 8i, N, , 810, but 81 and Ml, Ml alloy, cu, cu gold alloy diffuse into each other under high temperature and high pressure, and Sl and Ml
, N1 alloy, au, cu alloy as solid solution Hl
The stiffness of 81 in O and 81 in O are both about 5 wt% at room temperature), and they do not form a brittle layer and produce a good joint.

On the other hand, the insert material N4, N4 alloy, at.

Since the Ou alloy and the joining metal 2 are both metals, their weldability is basically extremely good and a good joint is formed.

(2) In the present invention, the present insert material is first brought into close contact with the ceramic by ion blasting or thermal spraying, but by employing ion blasting or thermal spraying, no matter how complex the shape of the ceramic, the insert material can be attached to the ceramic. Materials can be tightly fixed (it is difficult to use foil etc.).

(3) In the present invention, after the above-mentioned (2), a heating reaction acceleration treatment (the above-mentioned heating treatment or H-P treatment) is performed, which has the following effects.

■ 81. N4. 81 contained in SiO and the insert material are sufficiently diffused by high-temperature heating, and metallurgical bonding is achieved. In particular, when performing H-P treatment, the pressure load (three-dimensional gas pressure load) is used to remove creep deformation and plastic deformation of minute voids (minute voids generated during ion blasting or thermal spraying) at the ceramic interface of this insert material. to extinguish it and improve zygosity.

(2) No matter how complicated the shape of the ceramic is, H-P treatment is possible, and this insert material can be firmly bonded to the ceramic through a metallurgical diffusion reaction.

In other words, in the case of H-P treatment, the gas pressure is 5 at high temperature.
Because the pressure is applied evenly across all dimensions, it can be applied no matter how complex the ceramic interface is, and no cracks will occur.If pressure is applied in one dimension, uneven pressure tends to occur, so careful construction management is required. It is necessary to prevent cracking of ceramics that lack toughness), and since mere heat treatment does not naturally apply pressure,
There is no concern about ceramic cracking. Furthermore, since the insert material is not melted, there is also the advantage that there is no large reduction in the thickness of the insert material.

(4) In (3) above, the surface of the insert material of the subassembly subjected to the heat reaction acceleration treatment and the joining metal are brazed using a brazing material having a melting point lower than that of the insert material,
Although the joining is completed, the following effects are noted at this time.

(2) Generally, due to the difference in thermal expansion coefficient between the ceramic 1 and the bonding metal 2, cracks occur in the ceramic due to thermal stress generated during the cooling process after bonding. In contrast, in the present invention, by using a low melting point brazing filler metal, the cooling temperature range is reduced, the generated thermal stress is reduced, and the effect of preventing ceramic cracking is remarkable.

■ Insert material and bonding metal 2 are both metal,
Naturally, metal-to-metal welding is basically very good, and good joints can be formed using the aforementioned filler metals.

Example 1 8J with a plate thickness of 2111+ was ion blasted with 20μ of N1 in N4, and then subjected to HIP treatment at a temperature of 1200°C, an Ar gas pressure of 20kg/sw'', and a treatment time of 50 minutes.Next, the bonding metal An 8841 plate having a thickness of 3101 mm was placed opposite the above Ni surface, and brazed therebetween using Ag solder in an Ar atmosphere at a brazing temperature of 850° C. for several hours and 10 minutes.

As a result, a good joint with no cracks in 8i and N4 and no non-bonded parts over the entire surface was obtained.

Example 2 Si3N with a length of 10 days φ x 20 mm, N on the outer surface of a round bar
After i-50tS%Ou i50 /J ion plate ink, the temperature was 1050℃ and the Ar gas pressure was 20℃.
■Tofu, H-P treatment was performed for 15 minutes. Then,
Welding metal: inner diameter 1α25mmφ, outer diameter 16.25mφ
The Si, N, round rod coated with paste-like Ag solder was inserted into a Kovar cylinder with a length of 20 mm, and the brazing temperature was 8.
Brazing was performed at 00°C for 10 minutes in an Ar atmosphere.

As a result, there was no cracking in 813N4, and a good joint with no non-bonded parts over the metal surface of the cylindrical joint was obtained.

Example 3 A SiC cylinder with an inner diameter of 20 mm, an outer diameter of 25 mm, and a length of 50 m was coated with Ni-15% Or-! on its outer diameter surface. i. After 5% B alloy was plated with 10μ ions, the temperature was 1000.
℃, Ar gas pressure 20 to 97 m'', processing time 10 minutes H
Processing was performed. Next, the inner diameter 25. which is the joining metal.
25+o+φ, outer diameter 4525cmφ, length 50mm At
The above s1c cylinder coated with solder (5n-Pb-Zn system) was inserted into the cylinder, and soldered at a soldering temperature of 550° C. for 1 minute.

As a result, a good joint with no cracks in the slc and no non-bonded parts over the entire surface of the cylindrical joint was obtained.

Example 4 Inner diameter 20mφ, outer diameter 25w+Iφ, length 20. s,
Cu-10% Az alloy is applied to the outer diameter surface of the LC cylinder.
After 00μ plasma spraying, the temperature was 1 in an Ar atmosphere.
A heating reaction treatment was performed at 000° C. for 60 minutes. Next, welded metal with an inner diameter of 25.25 mm and an outer diameter of 45.25 mm.
At cylinder with ridge φ and length 20mm (with At wax on the inner surface)
The SaC cylinder was inserted into the sample (coated with z-sI system) and vacuum brazed at a brazing temperature of 600° C. for 2 minutes.

As a result, a good joint was obtained with no cracking in the sla and no non-bonded parts over the entire surface of the cylindrical joint.

[Brief explanation of the drawing]

FIGS. 1(A) to 1(0) are diagrams showing an embodiment of the method of the present invention in order of steps. Sub-agents 1) Meifuku agent Ryo Hagiwara -

Claims (1)

[Claims] 811N4. In the method of joining 810 series ceramic and metal, the ceramic 11 (Ml, N1 is 50-
After closely fixing either the N1 alloy containing the above or the Ou alloy containing Ou '% Ou of 50 or more as an insert material by ion blasting or thermal spraying, heat reaction acceleration treatment is performed to firmly bond both metallurgically. A method for joining ceramic and gold J4, characterized in that the surfaces of the insert material and the metal are then brazed using a brazing material having a melting point lower than the melting point of the insert material.