JPH01219072A - Metal-ceramic joined body - Google Patents

Abstract

PURPOSE:To easily obtain the subject joined body hardly causing the breaking of the ceramic member and having superior bonding strength, reliability and durability by inserting a projection fitted to a ceramic member into a recess having a specified shape in a metal member and by joining the members together with a brazing filler metal. CONSTITUTION:A projection 2 fitted to a ceramic member 1 is inserted into a recess 5 so stepped 3 as to increase the inside diameter at the inlet in a metal member 4. The entire inner circumferential surface of the recess 5 has been plated with Ni. A brazing filler metal 6 such as an active brazing filler metal is then put in the gap between the stepped part 3 and the projection 2 and the members 1, 4 are joined together.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a metal-ceramic bonded body formed by integrally bonding a ceramic member and a metal member.

(Conventional technology) Ceramics such as zirconia, silicon nitride, and silicon carbide are
Because it has excellent mechanical strength, heat resistance, and wear resistance, it is being put into practical use as a high-temperature structural material or wear-resistant material for gas turbine engine parts, engine parts, etc. However, since ceramics are generally hard and brittle, their moldability is inferior to that of metal materials. In addition, since it has poor toughness, it has low resistance to impact forces. For this reason, it is difficult to form mechanical parts such as engine parts only from ceramic materials, and they are generally used in the form of a composite structure in which a metal member and a ceramic member are bonded together.

At the time of joining, it is common to join the convex portion of the ceramic member to the recessed portion of the metal member by shrink fitting, brazing, or the like to form a joined body. At this time, stress concentration tends to occur at the joint end between the outer surface of the convex portion of the ceramic member and the inner surface of the recessed portion of the metal member, reducing the strength of the joined body against bending and twisting, and there is a large possibility that the ceramic member will break.

In order to prevent this stress concentration on the end of the joined body, a convex part is provided on the ceramic member and a concave part is provided on the metal member, and in the metal-ceramic joined body in which the convex part and the concave part are joined, the joining is performed by baking. JP-A-59-15 discloses a shape in which a groove is provided on the outer periphery of the convex portion and the recess is positioned such that the end of the groove becomes the joint end.
It is disclosed in Japanese Patent No. 9408.

(Problem to be Solved by the Invention) However, even if the present structure is implemented by mechanical bonding as described above, the end of the groove provided over substantially the entire circumference of the convex part of the ceramic member and the recess of the metal member still When the ceramic members come into contact with each other, excessive stress concentration occurs at that position, which reduces the strength of the joined body against bending and torsion, and the ceramic member is easily destroyed.

Furthermore, whether the end of the groove is an edge or a rounded part, stress concentration occurs to varying degrees, which reduces the strength of the joined body against bending and torsion, causing the ceramic member to deteriorate. They also have the same disadvantage of being easily destroyed. Furthermore, when the joined body is used in an atmosphere of combustion gas or the like, there is a drawback that the joined end portions are exposed to the combustion gas or the like, and the durability of the joined body tends to decrease.

The present invention aims to solve the above-mentioned problems and provide a metal-ceramic bonded body that is easy to manufacture and has high bonding strength at the bonded portion.

(Means for Solving the Problems) An example of the metal/ceramic bonded body of the present invention is a metal/ceramic bonded body having a structure in which a convex part provided on a ceramic member is inserted into a recessed part provided in a metal member and is integrally joined. In the ceramic bonded body, a stepped portion is provided so that the inner diameter of the recessed portion of the metal member becomes larger at the opening of the recessed portion, and at least a brazing material is interposed in the gap between the stepped portion and the convex portion of the ceramic member during bonding. It is characterized by:

Further, other examples of the metal-ceramic bonded body of the present invention include:
In a metal-ceramic bonded body having a structure in which a protrusion provided on a ceramic member is inserted into a recess provided in a metal member and integrally joined, a groove portion is formed over substantially the entire circumference near the joining end of the protrusion of the ceramic member. A brazing material is provided in the groove so that the brazing material is interposed between at least the end of the groove and the recess of the metal member.

Note that the joint end in the joined body of the present invention refers to the end of the joint between the protrusion of the ceramic member and the brazing material near the opening of the recess of the metal member, and as shown in FIG. The end 20 may be located at the groove of the convex portion, or may be located outside of the groove.

(Function) In the above-described configuration, a groove is provided over substantially the entire circumference near the joining end of the convex portion of the ceramic member, and a brazing material is interposed between at least the end of the groove and the recess of the metal member. , a stepped portion is provided so that the inner diameter of the recessed portion of the metal member becomes larger at the opening of the recessed portion, and at least a brazing material is interposed in the gap between the stepped portion and the convex portion of the ceramic member during bonding. Since the stress concentration in the ceramic member is reduced by the buffering effect of , it is possible to obtain a highly reliable metal-ceramic bonded body that is resistant to breakage due to bending or torsion. Furthermore, a groove is provided over substantially the entire circumference near the joining end of the convex portion of the ceramic member, and a brazing material is interposed between at least the end of the groove and the recess of the metal member. When provided in the groove, the presence of the brazing material in the groove prevents the ceramic member from coming off, increasing reliability against coming off.

Further, the joining between the metal member and the ceramic member is limited between the outer surface of the convex part of the ceramic member and the inner surface of the recess of the metal member, and the space or the intermediate made of a low-elastic body of a non-bonding substance or the When a film made of a substance is interposed to prevent the bonding between the tip surface of the convex part of the ceramic member and the bottom surface of the concave part of the metal member, stress concentration due to residual stress at the tip of the convex part and the joint end of the ceramic reflex member is alleviated, This is more preferable since it is possible to obtain a highly reliable metal-ceramic bonded body that is resistant to breakage due to bending or twisting.

When joining is performed by brazing, a brazing material is present between the groove provided in the convex part of the ceramic member and the recessed part of the metal member, and the increased thickness of the brazing material causes the joint end of the ceramic member to Brazing is preferable because it can reduce stress concentration caused by the difference in shrinkage between the metal member and the ceramic member due to temperature.

In addition, by brazing only the contact area between the outer surface of the protrusion and the inner surface of the recess of the metal member, the residual stress generated at the joint end can be alleviated, and the solder reacts with the ceramic member and the metal member, causing a gap between the two members. Since a strong bonded body is formed, not only the bonding strength from room temperature to high temperature becomes strong, but also a shrink-fitting effect is added when cooling from the bonding temperature, so high strength can be stably obtained, which is preferable.

The bonding portion can be limited to the above position by forming a thin film made of a substance that does not have bonding properties with wax on the tip surface of the convex part provided on the ceramic member, or by providing an intermediate body or space made of the substance on the metal member. The ceramic member may be disposed between the bottom surface of the concave portion and the tip surface of the convex portion provided on the ceramic member, or a combination thereof may be performed.

Graphite is an example of a material that does not bond with solders. The graphite film can be easily formed on the tip surface of the convex portion by applying a graphite particle suspension with a brush or spray, or by dipping. Further, as the intermediate body, it is preferable to use a low elastic body such as a sliver made of graphite fiber, felt, web, web sintered body, or woven fabric alone or in combination.

Furthermore, when the intermediate body is interposed between the tip surface of the convex portion and the bottom surface of the recessed portion, the joining area can be easily and reliably limited, thereby reducing residual stress generated at the joining end of the ceramic member after joining. This makes it possible to increase bond strength and reduce variation.

The interposition of the intermediate body made of a low elastic material not only has the effect of preventing the solder from joining with the bottom surface of the concave portion, but also prevents the tip of the convex portion caused by the difference in the amount of shrinkage between the ceramic member and the metal member upon cooling from the bonding temperature. It also has the effect of preventing mutual interference between the bottom surfaces of the recess and the generation of excessive residual stress in the joint, and the effect of efficiently penetrating the molten solder into the gap between the outer surface of the convex part and the inner surface of the recess. have.

The wax used to join ceramic parts and metal parts is
Preferably, it is an active metal solder containing an active metal element that can be chemically bonded to a ceramic member. The solder may be an alloy solder containing an active metal element, or a brazing material having a structure in which a metal base material is coated with an active metal element. Considering adjustment of the amount of active metal added to the brazing filler metal, ease of handling, and ease of manufacturing, it is preferable to use a brazing filler metal with a structure in which the active metal element is coated on the metal base. It is more preferable to use a brazing material having a structure in which an active metal element is vapor-deposited. Such active metal elements include Z when the ceramic members to be joined are ceramics containing at least nitrides and/or carbides.
r+ Ti, Ta+ If.

At least one metal element selected from the group consisting of V, Cr, La, Sc+ Y and Mo is preferable, and when the ceramic member to be joined is an oxide ceramic, at least one metal element selected from the group consisting of Be, Zr and Ti. One type of metal element is preferred.

Since the active metal solder has good wettability with ceramics, there is no need to perform special pretreatment such as metallization treatment on the ceramic member. Furthermore, if metal members are plated with Ni, they will have better wettability to the solder. Therefore, if this solder is used, it is possible to infiltrate the molten solder into a predetermined joining position using capillary action, so it is possible to manage the gap formed in the parts to be joined without placing the solder metal at the planned joining position. Just by doing this, you can achieve brazing with fewer defects such as bubbles and sink marks.

When brazing is performed using a solder that does not contain active metals, a metallized layer is provided at the planned joining position on the outer surface of the convex part of the ceramic member, and Ni plating is applied to the metallized layer, and more preferably, the inner surface of the recessed part of the metal member is plated with Ni. By applying Ni plating to the intended joining position, the same effect as in the case of the solder containing the active metal described above can be obtained. In this case, at the tips of the protrusions where no metallized layer is provided, the solder and ceramics do not react, so they are not joined, and a gap is formed between the tips of the protrusions and the bottoms of the recesses. Furthermore, it is more preferable to apply Ni plating to the intended joining position on the inner surface of the recess of the metal member, since this improves the wettability between the inner surface of the recess and the solder.

Furthermore, an activated metal foil is placed at a position where the outer surface of the convex portion of the ceramic member and the inner surface of the recessed portion of the metal member are to be joined,
By placing a brazing material that does not contain an active metal on the bottom surface of the recess of the metal member and performing brazing, the same effect as using an active metal brazing material can be obtained.

Further, the substantial joining is performed by mechanical joining such as press fitting, shrink fitting, cold fitting, etc., and the end of the groove provided over substantially the entire circumference at least near the joining end of the convex part of the ceramic member and the recessed part of the metal member. If the structure is such that the brazing metal is interposed between them, the end of the groove will come into contact with the recess of the metal member when joining is performed only by mechanical joining, and the excessive stress concentration generated at that position will be absorbed by the brazing metal. This is preferable because it can be reduced by the buffering effect of and further prevent corrosive gases such as high-temperature combustion gases from entering the bonding interface.

In addition, when the substantial joining is performed by mechanical joining as described above, at least the method of interposing a brazing material between the end of the groove and the recess of the metal member is such that the brazing material is inserted into the groove after mechanical joining. By raising the temperature of the joined body to the melting temperature of the disposed brazing material, the molten brazing material infiltrates between the end of the groove and the recess, making it possible to easily achieve the structure of the present invention. The brazing material used in the above case may be an active metal brazing material or may be a brazing material containing no active metal.

Furthermore, even when the actual joining is performed by mechanical joining such as press fitting, shrink fitting, or cold fitting, if the joining is performed only at the contact surface between the outer surface of the convex part of the ceramic member and the inner surface of the recessed part of the metal member, the ceramic This is preferable because residual stress due to mutual interference between the convex portion and the concave portion due to the difference in the amount of thermal expansion or contraction between the member and the metal member is eliminated.

The joint portion is limited to the above position by arranging an intermediate body or space between the bottom surface of the recess and the tip surface of the convex portion.

Further, when the substantial joining is performed by press-fitting, it is preferable that a predetermined space can be easily provided between the tip surface of the convex portion and the bottom surface of the concave portion by controlling the press-fitting distance.

Furthermore, when the substantial joining is carried out by press-fitting, as disclosed in Japanese Patent Application No. 61-285974 by the present applicant, the ceramic member and the metal member are housed in a container, for example.
It is preferable to carry out the press-fitting under a reduced pressure of about 0 Torr because compressed air does not remain in the space formed between the convex part of the ceramic member and the concave part of the metal member, and a bonded body with higher reliability can be obtained.

The ceramic material constituting the metal-ceramic bonded body of the present invention may be any material, but in consideration of practicality, silicon nitride, silicon carbide, sialon, zirconia, alumina, mullite, aluminum titanate, and cordierite are preferred. At least one ceramic material selected from the group consisting of: Which of these ceramic materials to use may be determined depending on the purpose of use of the metal-ceramic bonded body of the present invention and the type of metal material to be bonded.

(Example) FIGS. 1(a) to 1(d) are partial cross-sectional views showing an example of the metal-ceramic bonded body of the present invention.

In each embodiment, the convex portion 2 of the ceramic member 1 and the concave portion 5 of the metal member 4 are bonded, and a step portion 3 is provided so that the inner diameter of the concave portion 5 becomes larger at the opening of the concave portion, and the step portion 3 is provided at the time of bonding. An example is shown in which at least a brazing material is interposed in the gap between the portion 3 and the convex portion 2.

In the embodiment shown in FIG. 1(a), the entire inner surface of the recess 5 of the metal member 4 at the planned joining position is plated with Ni, and then the recess 5 is bonded using an active metal solder 6. This shows a structure in which the inner surface and the contact surface of the outer surface of the convex portion 2 of the ceramic member 1 are substantially entirely brazed. In addition,
When using a solder that does not contain a normal active metal, after Ni plating the inner surface of the recess 5 described above, a metallized layer is provided on the entire outer surface of the protrusion 2 at the planned bonding position. A similar bond can be achieved by applying

In the embodiment shown in FIG. 1(b), the recess 5 at the planned joining position
After Ni plating is applied to the inner surface of the convex portion 2 and graphite made of a solder and a non-bonding substance is applied to the tip surface 9 of the convex portion 2, the active metal solder 6 is used to bond the convex portion 2 to the concave portion 5. It is constructed by brazing the contact surface between the inner surface of the convex portion 2 and the outer surface of the convex portion 2, and a space 7 is provided between the bottom surface of the concave portion 5 and the tip surface 9 of the convex portion 2, and the structure is not joined. It shows.

In the embodiment shown in FIG. 1(c), the recess 5 at the planned joining position
The inner surface of the convex portion 2 is coated with Ni plating, the tip surface 9 of the convex portion 2 is coated with graphite, and the bottom surface of the concave portion 5 and the tip surface 9 of the convex portion 2 is coated with graphite.
Graphite felt 7, which is a low-elasticity intermediate made of a non-bonding substance, is provided at a position in contact with the wax, and then the active metal solder 6 is
By joining the concave portion 5 to the outer surface of the convex portion 2, a substantial bond is formed by brazing at the contact surface between the inner surface of the concave portion 5 and the outer surface of the convex portion 2, and the bottom surface of the concave portion 5 and the tip surface of the convex portion 2 are indicates an unbonded structure.

In the embodiment shown in FIG. 1(d), the recess 5 is
At least brazing of the inner surface of the stepped portion 3 provided in the opening is performed by press-fitting after applying Ni plating at the planned position, and brazing the active metal solder disposed between the stepped portion 3 and the convex portion 5. 1 shows a structure in which an active metal solder 6 is provided between the inner surface of the recess 5 forming the step 3 and the outer surface of the protrusion 2 by heating to a temperature and brazing. Further, at least the brazing of the inner surface of the stepped portion 3 may be performed after Ni plating is press-fitted into the predetermined position. Furthermore, as a method for arranging the brazing material between the step part 3 and the convex part 5, the brazing material may be placed in the predetermined position before press-fitting and then press-fitting, or if possible, after the press-fitting. A brazing filler metal may be placed at the predetermined position.

Furthermore, as another method of brazing, a molten brazing material may be poured between the stepped portion 3 and the convex portion 5 after press-fitting.

In addition, among the above-mentioned embodiments, FIGS. 1(a) and (b)
).

In the case shown in (c), the thickness of the gap g between the inner surface of the concave portion and the outer surface of the convex portion at the brazing temperature is preferably 300 μm or less, and more preferably 150 μm or less. If the gap g is 300 μm or more, the bonding strength will be low, and if the molten solder is penetrated using the capillary phenomenon described above, the rising height of the solder will be reduced and a predetermined bonding distance will be obtained. Undesirable. On the other hand, in brazing, it is preferable that the gap G between the inner surface of the recess and the outer surface of the protrusion forming the step at temperature is 1.5 to 4 times the gap g, and more preferably 2 to 3 times the gap G. preferable.

In addition, in the case shown in FIG. 1(d), the gap G is preferably 100 to 1200 μm at the brazing temperature, and 200 μm to 200 μm.
-800 μm is more preferable.

In the embodiment shown in FIGS. 1(a) to 1(d), if the gap G becomes larger than this, the thickness of the metal member 9 becomes thinner, which may not be good in terms of durability.

FIGS. 2(a) to 2(d) are partial cross-sectional views showing other examples of the metal-ceramic joined body of the present invention. In the embodiment shown in FIGS. 2(a) to 2(c), the convex portion 12 of the ceramic member 11 and the concave portion 14 of the metal member 13 are brazed using an active metal solder or a solder 15 containing no active metal. At the same time as joining, a groove 16 is provided along the entire circumference at a position corresponding to the vicinity of the joining end of the convex portion 12, and a solder 15, which is the same as the solder used for joining, is provided in this groove 16 continuously from the joining part. 16 end 17
An example is shown in which the solder 15 is provided in the groove 16 so that at least the solder 15 is interposed between the groove 16 and the recess 14.

In the embodiment shown in FIG. 2(a), the entire inner surface of the recess 14 of the metal member 13 at the planned joining position is plated with Ni, and then the recess 14 is bonded using the active metal solder 15. This shows a structure in which the inner surface and the contact surface of the outer surface of the convex portion 12 of the ceramic member 11 are substantially entirely brazed. Note that when using a solder that does not contain Ni such as ordinary Ag solder, the inner surface of the recess 14 described above may be
After plating, a metallized layer is provided on the entire outer surface of the convex portion 12 at the intended joining position, and the metallized layer is plated with Ni, thereby achieving a similar joining.

In the embodiment shown in FIG. 2(b), the recess 1 at the planned joining position is
After Ni plating is applied to the inner surface of the convex portion 12 and graphite made of a non-bonding substance is applied to the tip surface of the convex portion 12, the outer surface of the convex portion 12 and the concave portion are brazed using an active metal solder 15. 14, and the recess 1
4 and the tip surface of the convex portion 12, a space 18 is formed between the bottom surface of the concave portion 14 and the tip surface of the convex portion 12.
The figure shows a structure with .

In the embodiment shown in FIG. 2(c), the recess 1 at the planned joining position is
4, Ni plating is applied to the inner surface of the recess 14, and a graphite felt 19, which is a low-elastic intermediate made of a non-bonding material with the solder, is placed on the bottom of the recess 14, and on top of the graphite felt 19, the surface of the silver brazing plate is placed. After applying graphite to the tip surface of the convex portion 12, the convex portion 12 was inserted into the concave portion 14 to form a bonding assembly. Next, the joining assembly is heated in a vacuum to melt the solder, and by utilizing capillary action, the molten solder permeates into the intended joining position only to the outer surface of the convex portion 12 and the inner surface of the recessed portion 14. This shows a structure in which the bottom surface of the concave portion 14 and the tip surface of the convex portion 12 are not bonded to each other.

In the embodiment shown in FIG. 2(d), the convex part 12 of the ceramic member 11 and the concave part 14 of the metal member 13 are joined by mechanical joining such as press-fitting, and the entire vicinity of the joint end of the convex part 12 is An example is shown in which a groove 16 is provided around the circumference, and the solder 15 is provided in the groove 16 such that the active metal solder 15 is interposed at least between the end 17 of the groove 16 and the recess 14. In this embodiment, the step of applying Ni plating to the predetermined brazing position of the recess 14 may be performed before or after the mechanical bonding. moreover,
The brazing filler metal is placed in a predetermined position in the groove 16 before joining.
If possible, the groove portion 1 may be placed after the bonding.
It may be placed at 6. Furthermore, as another brazing method, a molten brazing material may be poured between the groove 16 and the recess 14 after the joining, and brazing may be performed.

As shown in FIGS. 2(b) and 2(c) above, in an embodiment in which the bottom surface of the concave portion 14 and the tip surface of the convex portion 12 are not in direct contact with each other due to the space 18 or the intermediate member made of graphite felt 19, This is preferable because stress concentration that would occur when the bottom surface of the concave portion 14 and the tip surface of the convex portion 12 are in contact with or bond to each other can be prevented.

The condition of the solder 15 in the groove 16 is shown in FIG. 3(a).
As shown in an enlarged view in (b), it is sufficient that at least the end 17 of the groove portion 16 is wrapped with the wax 15. That is, as shown in FIG. 3(a), a portion of the groove 16 is filled with wax 1.
5 may be present, or the wax 15 may be present throughout the groove portion 16 as shown in FIG. 3(b). However, the third
As shown in Figure (b), a structure in which the solder 15 is present throughout the groove 16 is preferable because it has high strength against pull-out, increases the buffering effect, and reduces stress concentration.

An actual example will be explained below.

1. First, a metal-ceramic bonded body of the present invention shown in FIGS. 1(a) to 1(c) was prepared. The manufacturing method is shown below.

A recess 5 with an inner diameter of 11.05 mm and a depth of 8 mm and a thin shaft portion with a diameter of 12 mm are provided at one end of a solution-treated Incoloy 903 round piece with a diameter of 18 mm, and a step is provided at the opening on the inner periphery of the recess over the entire circumference. A metal member 4 with a diameter of 1 and a diameter of 1 at one end of a silicon nitride sintered body made by pressureless sintering.
1. A ceramic member 1 provided with a convex portion 2 having a length of 10 mm was produced. Note that the step portion 3 was processed to have dimensions corresponding to the gap G, and was provided up to a position 02.5 mm inside the opening end of the recess.

The bottom corners of the recess 5 are chamfered CO,2, and the open end corners are tapered. Similarly, the edge portion at the tip of the recessed portion 2 is subjected to C0,5 taper processing, and the root portion is subjected to R2 curved surface processing.

Regarding these metal members and ceramic members, ``an active metal solder in which a 2 μm thick Ti layer was deposited on the surface of a 0.1 mm thick silver solder plate by the method shown in FIGS. 1(a) to (c) described above was used. A metal-ceramic bonded body of the present invention was obtained using the following.

At this time, the thickness of the Ni plating in FIGS. 1(a) to 1(c) was 10 μm, and the thickness of the graphite felt 8 used as an intermediate in FIG. 1(c) was 0.4 mm. In addition, the thickness of g in FIGS. 1(a) to (c) is 150μ
It was set as m.

Next, a metal-ceramic bonded body of the present invention shown in FIG. 1(d) was produced. The manufacturing method is shown below.

A ceramic member having the same material and shape as the ceramic member used in the joined body shown in FIGS. 1(a) to (c), and a first
A metal member was made of the same material as the metal member used in the joined body shown in Figures (a) to (c) and having the same shape except that the inner diameter of the recess 5 was 10.9 mm.

Regarding this metal member and ceramic member, the first
A metal-ceramic bonded body of the present invention was obtained using an active metal solder on which Ti was deposited by the method shown in Figure (d). At this time, the thickness of the Ni plating was 10 μm.

On the other hand, it does not have the step part shown in FIG. 4(a), which has the same shape as the metal member or ceramic member used in FIGS. Comparative Example 1 in which the surface contact surface was substantially entirely brazed, and a shape similar to that of the metal member or ceramic member used in FIG. 1(d).
A comparative example 2 was prepared in which the convex part 2 was press-fitted into the concave part 5 without having a stepped part as shown in FIG. 4(b). - The metal-ceramic joints shown in Figures 1 and 4 were all fabricated by brazing at a temperature of 850°C in a vacuum and then subjecting them to Incoloy 903 age hardening treatment. It is something.

For the prepared sample, the metal member 4 is fixed and a load is applied to the ceramic member 1 using the bending test device shown in Fig. 5, and the bending load at which the ceramic member breaks is measured and determined as the breaking bending load. At the same time, the fracture bending load was determined by varying the gap G in the example of the present invention. In addition, in Fig. 5, 1B = 40mm +
It was set as 5 mm.

The results are shown in Table 1.

From the results in Table 1, the one provided with the stepped portion of the present invention exhibited a higher fracture bending load than the proportional example without the stepped portion. Note that these results are collectively shown in FIGS. 6 and 7.

From the above results, in brazing, the gap G between the inner surface of the recess and the outer surface of the convex part that forms the step at the temperature
It can be seen that it is preferably 1.5 to 4 times, and more preferably 2 to 3 times.

In addition, in the case shown in FIG. 1(d), the gap G is preferably 100 to 1200 μm at the brazing temperature, and 200 μm to 200 μm.
It turns out that ~800 μm is more preferable.

The present invention is not limited to the embodiments described above, and can be modified in many ways. For example, in the embodiment shown in FIG. 1, the stepped portion is shaped like a step, but it may also be configured with a tapered portion or an R portion that becomes larger as it approaches the opening of the recess. Further, in the embodiment shown in FIG. 2, the groove section has a semicircular cross-sectional shape, but it goes without saying that other shapes may be used.

(Effects of the Invention) As is clear from the above detailed explanation, according to the metal-ceramic bonded body of the present invention, a stepped portion is provided so that the inner diameter of the recess of the metal member becomes larger at the opening of the recess, and Sometimes, by interposing at least a brazing material in the gap between the stepped part and the convex part of the ceramic member, or by providing a groove part over substantially the entire circumference near the joint end of the convex part of the ceramic member, at least the end of the groove part. By interposing a brazing material between the metal member and the concave part of the metal member, the stress concentration at the joint end of the ceramic member is reduced by the buffering effect of the brazing material, making metals and ceramics highly reliable and resistant to breakage when bent or twisted. A zygote can be obtained.

Further, in the metal-ceramic bonded body of the present invention, a part of the turbine impeller and the turbine shaft are made of silicon nitride ceramics,
If the other parts of the turbocharger rotor are made of high-strength metal, the brazing material will have a buffering effect, reduce residual stress, and prevent corrosive gases such as high-temperature exhaust gas from entering the joint interface, making it durable. A highly efficient turbocharger rotor with excellent performance and responsiveness can be obtained.

[Brief explanation of the drawing]

Figure 1 (a) to (d) and Figure 2 (a) to (d)
3(a) and 3(b) are partial sectional views showing an enlarged groove portion of the present invention, and FIG. 4(a), (b) is a partial cross-sectional view showing a metal-ceramic bonded body as a comparative example, the fifth side is a view showing the bending test device used in the test, and FIGS. 6 and 7 show the results in the example, respectively. It is a graph. 1.11...Ceramic member 2,12...Convex portion 3
...Stepped portion 4.13...Metal member 5
．． 14... Concavity 6.15... Active metal solder or solder containing no active metal 7.18... Space 8.19... Graphite felt 9... Tip surface of convex part 20... Joining Edge patent applicant: Nippon Insulator Co., Ltd. Figure 1 @ Figure 3 '20 Amazu \No \Non
Figure 4 (a) (b) Figure 5 Procedural amendment April 4, 1989 Director General of the Japan Patent Office Yoshi 1) Moon Yi 1. Indication of the case 1988 Hand-held Application No. 44211 2. Invention Name 3. Relationship with the case of the person making the amendment Patent applicant 4, agent 1, amend the scope of claims in the specification as follows. ``2.Claim ■: A metal member having a structure in which a protrusion provided on a ceramic member is inserted into a recess provided in a metal member and joined integrally.
In the ceramic bonded body, a stepped portion is provided so that the inner diameter of the recessed portion of the metal member is thicker at the opening of the recessed portion, and at least a brazing material is interposed in the gap between the stepped portion and the convex portion of the ceramic member during bonding. 2. A metal/ceramic bonded body having a structure in which a protrusion provided on a ceramic member is inserted into a recess provided in a metal member and integrally joined.
In the ceramic bonded body, a groove is provided over substantially the entire circumference near the joining end of the convex portion of the ceramic member, and a brazing filler metal is applied so that the brazing filler metal is interposed between at least the end of the groove and the recess of the metal member. A metal/ceramic bonded body characterized by being provided in a groove. 3. Joining only the outer surface of the convex portion and one inner surface of the recessed portion,
3. The metal-ceramic bonded body according to claim 1, wherein the top surface of the convex portion and the bottom surface of the concave portion are not bonded to each other. ” 2. “Figure 4” in the second line of page 6 of the specification is corrected to “Figure 3.” 3, page 7, line 5, page 8, line 2, page 9, line 17,
Page 11, line 9, page 12, line 1, page 13, line 9, page 16, lines 3 and 14, page 17, line 3 and 16
line, page 18, line 3, page 19, line 20, page 20, line 1
Correct "outer surface" in line 4 and line 6 on page 27 to "outer peripheral surface." 4, page 7, lines 5-6, page 8, line 2, page 9, line 17
Lines, page 12, line 2, page 13, lines 9-10, page 16, lines 2 and 13, page 17, lines 2-3 and lines 15-
"Inner surface" in line 16, line 3 on page 18, line 20 on page 19, line 14 on page 20, and line 6 on page 27 is corrected to "inner peripheral surface." 5. In the same page 7, lines 16-17, "the brazing material is between the recess" is changed to "between the recess, or between the convex part of the ceramic member and the stepped part provided in the recess of the metal member". Corrected to ``Niwa wood.'' 6. Correct "zygote" in line 6 of page 8 to "junction". 7. Correct "inner surface of recess 5" in line 19 of page 15 and line 8 of page 16 to "at least the inner circumferential surface of recess 5". 8. Correct "graphite felt 7" to "graphite felt 8" in lines 11-12 of page 16. 9. On page 19, line 11 of the same page, change “does not contain” to “
"Contains no active metals." 10, “Inner surface of recess 14” on page 19, line 17 of the same page is changed to “
"At least the inner circumferential surface of the recess 14". 11. Correct "the above-mentioned concave portion 2" in the 4th line of page 23 to "the above-mentioned protrusion 2." 12. In the drawings, Figures 1 to 5 have been corrected as shown in the attached correction figures. Representative Patent Attorney Akatsuki Sugimura Hidegai 1 person Figure 3 (ノ\ノFigure 4 (a) (b) ri 2 Figure 5

Claims (1)

[Scope of Claims] 1. In a metal-ceramic bonded body having a structure in which a convex part provided on a ceramic member is inserted into a recess provided in a metal member and joined together, the inner diameter of the recess of the metal member is 1. A metal-ceramic bonded body, characterized in that a stepped portion is provided so as to be larger at the opening of the recess, and at least a brazing material is interposed in a gap between the stepped portion and a convex portion of a ceramic member during bonding. 2. In a metal-ceramic bonded body having a structure in which a protrusion provided on a ceramic member is inserted into a recess provided in a metal member and joined together, substantially the entire circumference of the ceramic member near the joining end of the protrusion 1. A metal-ceramic bonded body, characterized in that a groove is provided throughout the groove, and a brazing filler metal is provided in the groove so that the brazing filler metal is interposed between at least an end of the groove and a recess of the metal member. 3. Joining only the outer surface of the convex portion and the inner surface of the concave portion,
3. The metal-ceramic bonded body according to claim 1, wherein the top surface of the convex portion and the bottom surface of the concave portion are not bonded to each other.