JP2002256410A - Ceramics-metal composite member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that when a sprayed layer of several millimeters thick is formed on the main surface of a large size of a ceramic base-material, the sprayed layer easily exfoliates from a main surface of a ceramic substrate at the boundary, when the thermal stress is applied due to a temperature cycle from outside or the like during spraying, or when it is machined. SOLUTION: The sprayed layer 3 consisting of a copper alloy or stainless steel, having thickness of 2 mm or more and 1/5 of the ceramic base material 2 or thinner, is formed all around the circumference of at least one main surface of the ceramic substrate 2 which has two main surfaces facing each other. The whole circumference of the main surfaces of the ceramic substrate 2 is thinned stepwise, and the sprayed layer 3 is coated on the thinned part so that the top face may be higher than the main surface and the side face may contact the step 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic-metal composite member in which a metal sprayed layer is applied to a main surface of a ceramic substrate having opposing main surfaces.

[0002]

2. Description of the Related Art In general, ceramics are known to have excellent properties as structural materials, such as higher rigidity, lighter weight and lower thermal expansion than metal materials. Because of these characteristics, application to various precision machine members that are used in, for example, semiconductor manufacturing equipment and require high-precision control has been attempted.

However, since ceramics are extremely hard, they are inferior in processing efficiency, and as a result, there has been a problem that members having various dimensions or members having complicated shapes have a high manufacturing cost. In addition, since ceramics are brittle materials, they tend to crack or crack during processing, and even if ceramics are applied to precision machine parts,
There has been a problem that simple fine correction processing cannot be easily performed like a metal material.

On the other hand, for example, in the case of a metal structure having a diameter of 250 to 500 mm and a thickness of about 10 to 20 mm, it has been extremely difficult to obtain an inexpensive member having dimensional accuracy on the order of nanometers (nm).

[0005] That is, in order to obtain dimensional accuracy on the order of nanometers, extremely careful processing must be performed, and the production cost increases. Although the use of a free-cutting material for a metal structure provides excellent workability, the free-cutting material is basically soft and low in rigidity. The above member is liable to be deformed, and as a result, a desired dimensional accuracy cannot be obtained.

[0006] Therefore, as a countermeasure against the disadvantages of the difficult-to-work and the lightweight characteristics of ceramics, which have excellent rigidity, a metal layer having a thickness that does not impair the characteristics of the ceramics is provided on the main surface of the ceramic base material. Attempts have been made to produce a composite member having both the characteristics of ceramics and metal by finely modifying the metal layer.

That is, it is an object of the present invention to obtain a composite member having both the characteristics of ceramics such as light weight and high rigidity and the free cutting characteristics of metal.

Conventionally, as a technique for forming a metal layer on the surface of a ceramic substrate, a plating method or a physical vapor deposition (PVD) method is used in addition to a thermal spraying method.
n), Chemical vapor deposition (CVD)
ition) are known.

[0009] Among them, the thermal spraying method uses a material such as metal, ceramics, and plastics as plasma, gas combustion heat, or the like.
It is a method of melting at high temperature by methods such as arc heat, laser heating, induction heating, etc., and spraying the base material as droplets by using the pressure generated by the volume expansion of the atmosphere due to air pressure or sudden temperature change, and coating the sprayed material. is there.

In the film forming mechanism by this thermal spraying method, the above-described droplet collides with the base material to flatten, and heat is instantaneously transferred from the droplet to the base material to cause thermal contraction when the droplet solidifies. Then, it is made to bite into the unevenness of the main surface of the base material and is joined by an anchor effect. Then, the particles of such droplets are successively piled up, and are repeatedly applied as described above, and are deposited in layers.

Next, although the plating method can be applied to a large-sized complicated-shaped member, there is a problem that the composition of the alloy layer is not uniform in the layer thickness direction. On the other hand, PVD method and CVD
In the method, it is difficult to form an alloy layer having a thickness of several hundred μm on the surface of a large-sized complicated-shaped ceramic substrate, in terms of manufacturing cost and equipment.

On the other hand, the material of the metal layer initially applied is not selected in view of ease of processing, but focuses only on the adhesion to ceramics. ), Nickel (Ni), iron (Fe) and other pure metals. Therefore, when finely modifying the metal layer, although it has better workability than ceramics, it is necessary to use a working fluid such as an abrasive, and the cleanliness that dislikes the rust of the metal layer and contamination of the members is low. It was unsuitable as a required precision member.

On the other hand, after forming a metallized layer only on a portion of the ceramic surface requiring high-precision processing, the surface of the metallized layer is roughened by shot blasting, and a copper alloy metal layer is formed thereon by a thermal spraying method. By forming
A ceramic member having free-cutting properties and capable of easily performing fine correction processing has been proposed (conventional example 1; Japanese Patent Application Laid-Open No. 8-919).
No. 67). According to this ceramic member, FIG.
As shown in the figure, the copper alloy layer 103 having excellent workability can be easily formed on the main surface of the ceramic base material 102 to a predetermined thickness, and the copper alloy layer can be formed without using a processing liquid. The layer 103 can be machined.

[0014]

However, the copper alloy layer 103 of the prior art 1 has a thickness of at most about 500 .mu.m, and has a diameter of about 250 to 500 mm and a thickness of about 10 to 20 mm. The thickness of the metal spray layer deposited on a large ceramic substrate as
In consideration of the machining allowance, it is necessary to form the ceramic base in units of several mm in a range that does not impair the rigidity of the ceramic base.

Therefore, the ceramic substrate 1 of the above-mentioned conventional example 1
When a copper alloy layer 103 having a thickness of several mm or more is applied to the metal layer 02, the copper alloy layer 103, which is a metal, generally has a larger thermal expansion than the ceramic substrate 102. For example, the thermal expansion coefficient of the ceramic substrate 102 is about 7 × 10 ⁻⁶ / ° C. (room temperature to 800 ° C.) for alumina (Al ₂ O ₃ ) ceramics, and the molybdenum deposited on the main surface of the ceramic substrate 102 The metallized layer made of a (Mo) -manganese (Mn) alloy is about 7.5 × 10 ⁻⁶ / ° C. (room temperature to 80 ° C.).
0 ° C.), and the thermal sprayed layer made of copper (Cu) alloy or stainless steel is about 15 × 10 ^{−6 to} 20 × 10 ⁻⁶ / ° C. (room temperature to 8 ° C.).
00 ° C.).

Therefore, for example, the ceramic substrate 102
When a ring-shaped sprayed layer having a thickness of 2 mm or more is applied over the entire periphery of the main surface of the disc-shaped ceramic base material 102 in consideration of the firing deformation of the ceramic base material 1, the thermal shrinkage stress of the sprayed layer is reduced.
02 acting in the center direction of the ceramic substrate 10
2 has a problem of peeling from the outer peripheral portion. This is because when thermal stress due to a temperature cycle from the outside is applied to the thermal sprayed layer having the residual stress, the interface is easily separated from the main surface of the ceramic substrate 102.

Further, when machining the obtained ceramic member, there is also a problem that the interface between the ceramic base material 102 and the sprayed layer is peeled off at the outer peripheral portion of the ceramic member due to the residual stress of the sprayed layer, and the mouth is opened. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a ceramic material comprising a large ceramic substrate having a main surface coated with a thick sprayed layer having a thickness of several mm. In a metal composite member, a ceramic-metal composite member that does not easily cause interfacial delamination from the main surface of a ceramic base material during thermal spraying, when thermal stress is applied from the outside due to a temperature cycle, or when machining is performed. To provide.

[0019]

Means for Solving the Problems Ceramics of the present invention
The metal composite member has a thickness of not less than 2 mm and 1/1 / th of the thickness of the ceramic base material on the entire periphery of at least one of the two main surfaces of the ceramic base material having the opposing main surfaces.
A ceramic-metal composite member having a thermal sprayed layer made of a copper alloy or stainless steel having a thickness of 5 or less,
The ceramic base material is formed such that the entire periphery of the peripheral edge of the main surface is reduced in a stepped shape, and the thermal spraying is performed such that an upper surface protrudes above the main surface and a side surface is in contact with the step at the thinned portion. Characterized in that the layer is applied.

According to the present invention, since the thermal shrinkage stress of the thermal spray layer acts on the step of the ceramic substrate having a strong compressive force to lock the thermal spray layer by the above configuration, the thermal spray layer is fixed from the main surface of the ceramic substrate. Has the effect of making it difficult for the interface to peel.

In the present invention, preferably, the depth of the step is 0.3 mm or more.

According to the present invention, the above-mentioned configuration further enhances the effect that the thermal sprayed layer is locked at the step and the thermal sprayed layer is less likely to be separated from the main surface of the ceramic base material at the interface.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The ceramic-metal composite member of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing an example of an embodiment of the ceramic-metal composite member of the present invention, and FIG. 2 is an enlarged sectional view of a main part of the ceramic-metal composite member of FIG. 1 and 2, reference numeral 1 denotes a ceramic-metal composite member mainly composed of a ceramic substrate 2 and a sprayed layer 3 made of a copper alloy or stainless steel.

The ceramic substrate 2 of the present invention has a copper alloy having a thickness of 2 mm or more and a thickness of 1/5 or less of the thickness of the ceramic substrate 2 over the entire periphery of at least one peripheral edge of both main surfaces. Alternatively, a thermal sprayed layer 3 made of stainless steel is adhered, and the ceramic substrate 2 is formed such that the entire periphery of the peripheral surface of the main surface is reduced in a step-like shape, and the upper surface of the thin portion is higher than the main surface. The thermal spray layer 3 is applied so as to protrude upward and to contact the side surface with the step 4 (the inner side surface 5 of the step 4).

Preferably, the depth of the step 4 is 0.3
mm or more. That is, the side surface of the thermal spray layer 3 is in contact with the step 4 by 0.3 mm or more, and the contact portion of 0.3 mm or more constitutes the engaging portion 7 with the step 4.

The thermal spray layer 3 of the present invention comprises a metallized layer made of a Mo—Mn alloy, a plated layer made of Ni,
The thermal spraying layer is formed via an underlayer 8 on which a thermal spray layer made of an Al alloy is sequentially applied.

The ring-shaped step 4 provided on the entire periphery of the main surface of the ceramic base 2 has an engagement portion 7 on its inner surface 5 so as to be in contact with the sprayed layer 3 by 0.3 mm or more. Is good. When the depth of the engagement portion 7 is less than 0.3 mm, the thermal shrinkage stress of the thermal sprayed layer 3 largely acts on portions other than the engagement portion 7, and together with the internal stress generated in the thermal sprayed layer 3, the ceramic base material is used. 2, the thermal sprayed layer 3 is likely to be peeled off from the outer peripheral portion. If the upper surface of the thermal spray layer 3 is at or below the same position as the main surface, it is not possible to secure a processing allowance for the thermal spray layer 3 over the entire periphery of the main surface of the ceramic base material 2. As a result, it is not possible to easily perform a fine correction process of a predetermined size by grinding the thermal sprayed layer 3, and it becomes difficult to perform a precision process.

Accordingly, the depth of the step 4 is about 0.3 mm or more, more precisely 0.35 mm in consideration of the thickness of the underlayer 8.
It would be fine if more.

The ceramic substrate 2 of the present invention is made of, for example, alumina (Al ₂ O ₃ ) ceramics or the like, and comprises alumina (Al ₂ O ₃ ), silica (SiO ₂ ), magnesia (Mg
O), calcia (CaO), etc., after appropriately adding an organic binder, a solvent, and the like to the raw material powder and mixing the mixture, molding the mixture into a predetermined shape by, for example, a conventionally known press molding method. It is manufactured by firing at a high temperature.

The thermal sprayed layer 3 made of the copper alloy or stainless steel of the present invention has a thickness 6 of 2 mm or more and 1/5 or less of the thickness of the ceramic substrate 2, and the upper surface thereof has a ceramic base. It is necessary that the material 2 protrudes upward from the main surface and the side surface is in contact with the step 4.

That is, when the thickness of the thermal sprayed layer 3 made of a copper alloy or stainless steel is less than 2 mm, in the case of a large ceramic substrate 2 having a diameter exceeding 250 mm, grinding is performed in accordance with various dimensions and complicated shapes. The thickness of the workpiece to be fine-corrected with high precision after approaching the predetermined dimension is insufficient, which is inappropriate. When the thickness of the thermal spray layer 3 exceeds ５ of the thickness of the ceramic substrate 2, the thermal stress generated inside the thermal spray layer 3 causes the thermal spray layer 3 to easily cause interface peeling from the outer peripheral portion of the ceramic substrate 2. Become. Further, it is necessary that the thermal spray layer 3 protrudes from the main surface of the ceramic substrate 2 to form a grinding allowance.

A metallized layer is applied to at least the bottom surface (thin portion) of the step 4 of the ceramic substrate 2. That is, the metallized layer can also be formed on the inner side surface 5 of the step 4. This metallized layer is formed by applying a metal paste containing Mo powder, Mn powder and a small amount of SiO ₂ to the bottom surface of the step 4 of the ceramic base 2 and firing the same at a high temperature to form the step of the ceramic base 2. 4 is baked and adhered to the bottom surface. In this case, the Mn and SiO ₂ components in the Mo—Mn alloy combine with, for example, an alumina-based sintered body in the ceramic substrate 2, and Al ₂ O ₃ is formed on the interface between the main surface of the ceramic substrate 2 and the metallized layer. It is considered that the composite oxide is firmly adhered by forming a composite oxide of Mn and glass.

The metallized layer is firmly adhered to the ceramic substrate 2 and a thermal spray layer 3 made of a copper alloy or stainless steel is applied to the ceramic substrate 2 via a Ni plating layer and a thermal spray layer made of a Ni-Al alloy. 2 functions as a base metal film for bonding. The thickness of the metallized layer is improved by increasing the adhesion strength of the metallized layer to the ceramic substrate 2 by forming the above-mentioned composite oxide, and by improving the strength of the metallized layer itself. From the viewpoint of preventing interfacial peeling of
A range of 25 μm is preferred.

On the upper surface of the metallized layer, a Ni plating layer is applied by a conventionally known electrolytic plating method or electroless plating method. This Ni plating layer is formed by adding Ni to the metallized layer.
-It functions as a base metal film for firmly applying a thermal spray layer made of an Al alloy. The Ni plating layer satisfactorily absorbs and relaxes the thermal stress caused by the difference in thermal expansion between the metallized layer and the thermal sprayed layer made of the Ni-Al alloy.

Further, the upper surface of the Ni plating layer has an arithmetic mean roughness Ra of about 0.5 to obtain an anchor effect at the time of joining.
The surface is preferably roughened to about 5 to 3 μm. Also, N
The i-plated layer preferably has a thickness of about 0.5 to 15 μm in order to firmly adhere to both the metallized layer and the sprayed layer made of a Ni—Al alloy.

Next, the N deposited on the upper surface of the Ni plating layer
The thermal spray layer made of the i-Al alloy functions as a base metal layer for depositing the thermal spray layer 3 made of a copper alloy or stainless steel. Further, the thermal sprayed layer made of the Ni-Al alloy has a thickness of 5 to 5 from the viewpoints of good bonding property with the Ni plating layer and suppression of internal stress generated in the thermal sprayed layer itself.
About 1500 μm is preferable. Further, the thermal sprayed layer made of a Ni-Al alloy has a high adhesion to the Ni plating layer.
Is 80 to 95% by weight, and the content of Al is 5%.
A composition range of ２０20% by weight is preferred.

Then, a metallized layer made of a Mo—Mn alloy, a Ni plating layer, and a thermal sprayed layer made of a Ni—Al alloy are sequentially applied via an underlayer 8 to form a thermal sprayed layer made of a copper alloy or stainless steel. 3 can be firmly applied.

Incidentally, the thermal expansion coefficient of the thermal sprayed layer 3 made of copper alloy or stainless steel is about 15 × 10 ^{-6 to} 20 × 10
⁻⁶ / ° C. (room temperature to 800 ° C.), whereas the thermal expansion coefficient of the ceramic substrate 2 is about 7 × 10 ⁻⁶ / ° C. (room temperature to 80 ° C.).
0 ° C). However, a metallized layer having a thermal expansion coefficient of about 7.5 × 10 ⁻⁶ / ° C. (room temperature to 800 ° C.) from the ceramic substrate 2 side, and a thermal expansion coefficient Is about 13 × 10 ⁻⁶ / ° C. (room temperature to 800 ° C.) and a thermal expansion coefficient is about 15 ×
^10-6 to 18 * ^10-6 / C (room temperature to 800C) Ni-
A sprayed layer made of an Al alloy is sequentially applied.

Accordingly, the thermal sprayed layer 3 of the present invention is, for example, -40.
The stress caused by the difference in thermal expansion between the ceramic substrate 2 and the sprayed layer 3 generated between the ceramic substrate 2 and the sprayed layer 3 is better due to the base layer 8 even when repeatedly exposed to a temperature cycle of up to 80 ° C. or when the temperature changes during spraying. It is absorbed and relaxed. Further, a step 4 is provided on the entire periphery of the ceramic substrate 2, and the sprayed layer 3 is formed on the inner side surface 5 of the step.
Are engaged at a predetermined depth, so that the heat shrinkage stress of the sprayed layer 3 is effectively locked on the inner side surface 5 of the step 4. As a result, even when the thermal spraying layer 3 is ground, the thermal spraying layer 3 does not peel off from the ceramic substrate 2 at the interface.

The ceramic substrate 2 of the present invention may have a shape having a main surface opposed thereto, and may have a disk shape, a rectangular parallelepiped shape,
The shape of a flat plate or other planar view may be a complicated shape.

[0041]

Embodiments of the present invention will be described below.

(Example) First, a disk-shaped ceramic substrate 2 having a diameter of 250 mm and a thickness of 20 mm made of an alumina sintered body having a purity of 99% by weight was prepared. A ring-shaped step having a width of 4 mm and various depths (see Table 1 below) having an inner surface 5 substantially vertical as shown in FIG. 2 around the entire periphery of both main surfaces of the ceramic substrate 2. 4 was formed by grinding.

Next, a metal paste containing 89% by weight, 6% by weight, and 5% by weight of Mo, Mn, and SiO ₂ , respectively, was placed on the bottom surface of the step 4 of the ceramic base 2 by 10%.
It was printed and coated to a thickness of １５15 μm, dried, and fired at 1400 ° C. in a humidified forming gas. Thus, a metallized layer made of a Mo—Mn alloy was applied to the bottom surface (thin portion) of the step 4 of the ceramic substrate 2.

Thereafter, a Ni plating layer is deposited on the metallized layer to a thickness of about 2 μm by electrolytic plating, and then the surface of the Ni plating layer is coated with Ra to a thickness of 10 μm by sandblasting.
The surface was roughened to about m.

Next, Ni (95) was formed on the surface of the Ni plating layer.
% By weight) -Al (15% by weight) alloy was applied by arc spraying. At that time, the spray gun current was 30
A, the coating was applied to a thickness of about 50 μm under the spraying conditions of a voltage of 150 V and a discharge pressure of 49 MPa.

Subsequently, a metallized layer, a Ni plating layer, and a sprayed layer are used as an underlayer 8 on which a Cu (59% by weight) -Zn (38% by weight) -Pd (3% by weight) copper alloy or A sprayed layer made of a stainless steel of an Fe (74 wt%)-Cr (18 wt%)-Ni (8 wt%) alloy was applied by a flame wire spraying method. At that time, the sprayed layer 3 was formed to have a thickness of 2 mm and 4 mm under the spraying conditions of a spray gun current of 30 A, a voltage of 150 V, and a discharge pressure of 49 MPa (megapascal).

On the other hand, as a comparative example, without providing the step 4,
A ceramic substrate 2 having the same dimensions as in the above-described embodiment is provided with a width of 4 mm
A sample in which a 2 μm-thick thermal spray layer 3 made of a copper alloy having the same composition as described above was applied via an underlayer 8 similar to the above was produced.

Using the evaluation sample thus obtained,
First, the adhesion between the thermal sprayed layer 3 and the ceramic substrate 2 at the time when the thermal sprayed layer 3 was formed was inspected using an optical instrument, but no interfacial peeling was observed in the product of the present invention. On the other hand, in the comparative example, peeling was observed at the interface between the ceramic base material 2 and the sprayed layer 3 made of a copper alloy at the stage when the sprayed layer 3 was formed.

Next, the protruding portion, which is the protruding portion of the thermal spray layer 3 in the thermal spraying step, is machined to have the same dimension as the outer peripheral dimension of the ceramic substrate 2.
Was inspected using an optical instrument. Table 1 shows the results.

[0050]

[Table 1]

As is clear from Table 1, in the sample No. 12 of the comparative example, the sprayed layer 3 made of a copper alloy having a thickness of 2 mm was formed in a ring shape with a width of 4 mm around the entire periphery of the main surface of the ceramic base 2. The peeling was recognized at the interface with the ceramic substrate 2 only by the formation.

On the other hand, even if the step 4 is provided on the ceramic base material 2, in the sample No. 1 in which the engaging portion 7 is out of the range of the present invention,
Peeling was observed at the interface between the thermal sprayed layer 3 and the ceramic substrate 2 after the mechanical processing. Also, in sample No. 11, the thermal sprayed layer 3 did not protrude from the main surface of the ceramic substrate 2, and a grinding allowance for precision processing by grinding the thermal sprayed layer 3 was not obtained.

In contrast, none of the products of the present invention showed any peeling, indicating that they had a bonding strength sufficient to withstand the thermal history of the thermal spraying process and the subsequent machining.

It should be noted that the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention. For example, as shown in FIG. 3, the inner surface 5 of the step 4 may be provided in a step-like shape such that the width of the sprayed layer 3 decreases in the depth direction. In this case, the width of the thermal spray layer 3 may be increased in the depth direction. That is, a configuration in which the thermal sprayed layer 3 penetrates into the inner side surface 5 in the depth direction can be adopted. Further, as shown in FIG. 4, the shape of the inner surface 5 of the step 4 may be a curvedly concave shape. Further, as shown in FIG. 5, the shape of the inner surface 5 of the step 4 is such that the width of the sprayed layer 3 gradually increases in the depth direction, that is, the shape of the inner surface 5 has an inversely tapered shape. It can be configured.

3 to 5, the contact area of the sprayed layer 3 with the inner side surface 5 is improved, and
Since the degree of locking is strengthened, the same or more advantageous effects as in the above embodiment can be obtained.

[0056]

According to the present invention, the thickness of the ceramic substrate having a thickness of not less than 2 mm and at least one-third of the thickness of the ceramic substrate is formed on the entire periphery of at least one of the two main surfaces of the ceramic substrate having the opposing main surfaces.
A ceramic-metal composite member having a thermal sprayed layer made of a copper alloy or stainless steel having a thickness of 5 or less,
The ceramic substrate has a main surface whose entire periphery is thinned in a step shape, and a sprayed layer is applied to the thin portion so that the upper surface protrudes above the main surface and the side surfaces contact the step. Therefore, the thermal contraction stress of the thermal spray layer acts on the step of the ceramic base material having a strong compressive force, so that the thermal spray layer is locked.
Therefore, even if a thermal spray layer with a thickness of 2 mm or more is applied to the main surface of a large ceramic base material, when thermal stress is applied from the outside due to a temperature cycle or the like during thermal spraying, or when machining, A ceramic-metal composite member that is lightweight, has high rigidity, and has easy-cutting properties without easily causing interface delamination from the main surface of the base material can be obtained. As a result, the diameter is 2
It is possible to provide an inexpensive member having dimensional accuracy on the order of nanometers for a large structure having a size of 50 mm or more.

In the present invention, preferably, the depth of the step is 0.3
When the thickness is not less than mm, the function and effect that the thermal sprayed layer is locked to the step and the thermal sprayed layer is less likely to be separated at the interface from the main surface of the ceramic base material is further improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a ceramic-metal composite member of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the ceramic-metal composite member of the present invention.

FIG. 3 is an enlarged sectional view of a main part showing another example of the embodiment of the ceramic-metal composite member of the present invention.

FIG. 4 is a main part enlarged sectional view showing another example of the embodiment of the ceramic-metal composite member of the present invention.

FIG. 5 is an enlarged sectional view of a main part showing another example of the embodiment of the ceramic-metal composite member of the present invention.

FIG. 6 is a sectional view showing a conventional ceramic-metal composite member.

[Explanation of symbols]

 1: Ceramic-metal composite member 2: Ceramic base 3: Sprayed layer 4: Step 5: Inner surface 6: Thickness of sprayed layer 7: Engagement portion

Claims (2)

[Claims] 1. A ceramic substrate having an opposing main surface having a thickness of 2
mm or more and 1/5 of the thickness of the ceramic substrate
The following is a ceramic-metal composite member to which a sprayed layer made of a copper alloy or stainless steel is applied, wherein the entire circumference of the periphery of the main surface of the ceramic base is reduced to a step-like shape. A ceramic-metal composite member, wherein the thermal spray layer is applied to the thin portion so that an upper surface protrudes above the main surface and a side surface contacts a step. 2. The ceramic-metal composite member according to claim 1, wherein the depth of the step is 0.3 mm or more.