JPH0733545A - Bonding structure of ceramic member and metal member and ceramic-metal bonded body - Google Patents

Abstract

(57) [Abstract] [Purpose] Only by fitting the ceramic member and the metal member together, firm joining is possible, the ceramic member does not crack even at high temperatures, and the joining of both members is insufficient even at low temperatures. (EN) Provided is a joint structure of a ceramic member and a metal member, which never happens. [Structure] The ceramic member 1 is formed with a tapered hole 11 whose inner diameter gradually increases from the inlet to the back, and the metal member 2
Is formed with a convex portion 21 having an outer diameter gradually increasing from the lower end portion toward the front end portion and a slit 22 formed in the central axis direction. By fitting the convex portion 21 of the member 2,
The ceramic member 1 and the metal member 2 are integrated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of a ceramic member and a metal member. More specifically, it relates to a joining structure for integrating a ceramic member and a metal member having different thermal expansion coefficients.

[0002]

2. Description of the Related Art Conventionally, as a method of joining a ceramic member and a metal member, for example, a method of directly joining two members using an anaerobic adhesive, an instant adhesive or the like, one of the two members is used. To form a concave portion on the other member and a convex portion on the other member to fit the two members together, or to bring the two members to be pressed into contact with each other into contact with each other while pressurizing them to cause a relative motion and to generate a frictional heat. There is a method such as friction welding in which the vicinity is heated and pressed. In recent years, along with the expansion of applications of ceramics, the advent of a solid and highly reliable joint structure between a ceramic member and a metal member has been demanded.

[0003]

However, a member joined by the method of directly joining two members using the anaerobic adhesive or the instant adhesive of the above-mentioned conventional example, the member is bonded at high temperature. If both members are separated due to a decrease in force, or if a large force acts on the joint portion, there is a risk that both members will separate due to insufficient adhesive strength. In addition, a method of forming a concave portion on one member and a convex portion on the other member of the two members and fitting both members together is used for joining the ceramic member and the metal member to form a concave portion on the ceramic member. When the convex portion formed on the metal member is fitted, the coefficient of thermal expansion of ceramics is small, and the coefficient of thermal expansion of metal is generally larger than that of ceramics. Therefore, even if both members are sufficiently fitted at room temperature. , At a high temperature, the metal expands more than the ceramics, which may cause the ceramics to crack.
At a low temperature, the metal shrinks more than the ceramic, so that the fitting of both members becomes insufficient and the convex portion of the metal member easily comes out from the concave portion of the ceramic member. Further, although the method of friction welding is suitable for pressure welding between dissimilar metals, when the ceramic member and the metal member are joined together, the hardness of the ceramic member is large, so that the vicinity of the joining surface of both members is heated and joined by friction heat. There is a problem that it is difficult to join both members.

In view of the above circumstances, the present invention enables firm joining only by fitting a ceramic member and a metal member having a large coefficient of thermal expansion, and the ceramic member does not crack even at a high temperature, and at a low temperature. However, it is an object of the present invention to provide a joint structure of a ceramic member and a metal member in which joining of both members is not insufficient.

[0005]

The joining structure of the ceramic member and the metal member of the present invention is a joining structure of the ceramic member and the metal member having different thermal expansion coefficients, and the inner diameter of the ceramic member goes from the inlet to the back. The taper hole is formed to be gradually larger, and the metal member is formed such that the outer diameter is gradually increased from the lower end portion to the front end portion, and the convex portion is formed with a slit in the central axis direction. The convex portion of the metal member is fitted in the tapered hole of the member.

[0006]

According to the joining structure of the ceramic member and the metal member of the present invention, the outer diameter formed on the metal member is from the lower end to the tip end in the tapered hole in which the inner diameter is gradually increased from the inlet to the back. Since the structure is such that the convex part that gradually increases in size toward the part and has a slit in the central axis direction is fitted, if the convex part of the metal member is fitted into the tapered hole of the ceramic member at room temperature, at high temperature Since the coefficient of thermal expansion of the metal member is higher than that of the ceramic member, even if the convex portion of the metal member expands in the tapered hole of the ceramic member, the expansion amount is in the central axis direction of the convex portion of the metal member. Since it is absorbed by the formed cracks, there is no risk of the ceramic member cracking due to the difference in thermal expansion at high temperatures. Although it contracts in the tapered hole of the material, the convex portion of the metal member is locked in the tapered hole of the ceramic member by the wedge action of the taper hole of the ceramic member, so the convex portion of the metal member falls out of the tapered hole of the ceramic member. There is no such thing, and a tightly coupled state is maintained.

[0007]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 shows a joint structure of a ceramic member 1 and a metal member 2 which is an embodiment of the present invention. This joining structure has a taper hole 11 formed in the ceramic member 1,
The convex portion 21 having the slit 22 formed on the metal member 2 is fitted.

As shown in FIG. 2, the ceramic member 1 is a columnar member having a tapered hole 11 whose inner diameter gradually increases from the inlet to the back at the lower end of the columnar member. There is. When a convex portion 21 (see FIG. 4) of the metal member 2 described later is fitted in the tapered hole 11, taper (ab) / l (a; inner diameter of the taper end portion of the tapered hole 11, b) The inner diameter of the entrance of the taper hole 11, l; the length from the entrance of the taper hole 11 to the taper end portion) becomes larger, the convex portion 21 of the metal member 2 becomes more difficult to come out of the taper hole 11 of the ceramic member 1, but the taper In order to increase the diameter of the taper hole 11, the length l from the entrance of the taper hole 11 to the end of the taper is made constant, and the inner diameter a of the taper end of the taper hole 11 is made larger than the inner diameter b of the entrance of the taper hole 11. If the inner diameter a at the taper end of the taper hole 11 and the inner diameter b at the entrance of the taper hole 11 are kept constant and the length l from the entrance of the taper hole 11 to the taper end is increased, the convex portion of the metal member 2 In some cases, it may be inappropriate due to the shape and size of 21. Therefore, the taper of the tapered hole 11 formed in the ceramic member 1 must be set to the most appropriate value in relation to the shape, size, etc. of the convex portion 21 of the metal member 2. In this embodiment, the tip of the ceramic member 1 is formed in a conical shape, but it may be formed in any shape depending on the purpose of use.

As shown in FIG. 4, the metal member 2 is a cylindrical member and is formed at the upper end of the cylindrical member such that the outer diameter gradually increases from the lower end to the distal end. The convex portion 21 is formed. Then, as shown in FIGS. 3 and 4, a cross-shaped slit 22 is formed in the central axis direction of the convex portion 21.
Are formed. In the present embodiment, the shape of the slit 22 is cruciform in consideration of strength and the like, but it is possible to make any shape.

Further, an annular recess 23 is formed on the peripheral side of the lower end of the projection 21 in order to fully exert the function of the slit 22, and the bottom of the annular recess 23 is formed by the slit 22. Is substantially aligned with the lower end of the center axis direction of. In the present embodiment, the lower end of the columnar body is formed with a concave notch 24 for connecting with another member (not shown), and the leg portions 25 at both ends are formed with bolt holes 26. However, it is possible to make the shape according to the member connected to the lower end of the cylindrical body.

Next, a method of fitting the convex portion 21 formed in the metal member 2 into the tapered hole 11 formed in the ceramic member 1 will be described. First, at room temperature, the tip of the convex portion 21 of the metal member 2 is attached to the taper hole of the ceramic member 1.
Abut near the entrance of 11. Next, the ceramic member 1
The tip portion of the convex portion 21 of the metal member 2 that abuts the entrance of the tapered hole 11 is strongly pressed, and the gap between the slits 22 formed on the convex portion 21 of the metal member 2 becomes small, so that the convex portion of the metal member 2 is convex. When the outer diameter of the tip of the portion 21 becomes slightly smaller than the inner diameter of the inlet of the taper hole 11 of the ceramic member 1, the tip of the convex portion 21 of the metal member 2 goes from the inlet of the taper hole 11 of the ceramic member 1 to the back. Insert it. Then, the convex portion 21 formed in the metal member 2 is formed in the tapered hole 11 formed in the ceramic member 1.
Are fitted and the ceramic member 1 and the metal member 2 are integrated.

As described above, at room temperature, the inside diameter formed in the ceramic member 1 gradually increases from the inlet to the inside, and the outside diameter formed in the metal member 2 extends from the lower end to the tip. When the convex portion 21 having the slit 22 in the central axis direction is fitted in the metal member 2 at a high temperature, the coefficient of thermal expansion of the metal member 2 is larger than that of the ceramic member 1. 2 convex
21 expands in the tapered hole 11 of the ceramic member 1,
Since the expansion amount is absorbed by the slit 22 formed in the central axis direction of the convex portion 21 of the metal member 2, there is no risk of the ceramic member 1 cracking due to the difference in thermal expansion at high temperature. Further, when the temperature is low, the convex portion 21 of the metal member 2 contracts in the taper hole 11 of the ceramic member 1, but the convex portion 21 of the metal member 2 is formed by the wedge action of the taper hole 11 of the ceramic member 1 in the ceramic member 1. Since it is locked in the tapered hole 11, the convex portion 21 of the metal member 2 does not fall out from the tapered hole 11 of the ceramic member 1. Therefore, it is possible to obtain a solid and highly reliable joint structure between the ceramic member 1 and the metal member 2.

To remove the convex portion 21 of the metal member 2 fitted in the tapered hole 11 of the ceramic member 1, the metal member 2 may be pulled to the opposite side of the ceramic member 1. That is, by pulling the metal member 2 to the opposite side of the ceramic member 1, the gap between the slits 22 formed on the protrusion 21 of the metal member 2 becomes smaller, and the outer diameter of the tip of the protrusion 21 of the metal member 2 becomes smaller. When the inside diameter of the taper hole 11 of the ceramic member 1 becomes slightly smaller than the inner diameter, the tip of the convex portion 21 of the metal member 2 comes off the taper hole 11 of the ceramic member 1.

Next, the ceramics in this embodiment
A case where the metal bonded body A is actually used will be described.
When assembling the vehicle body, it is necessary to position and weld the respective panel parts with high precision, but a considerably high heat is applied to the assembly jig used for this purpose. Generally, in a vehicle body assembly jig, as shown in FIG. 5, one or two locate pins 3 are provided on each of the panel 4 and other parts, and clamps 5 and the like are provided at both ends and in the middle thereof at an appropriate pitch. Ceramics in this embodiment
It is very suitable to use the metal bonded body A for the locate pin 3.

That is, as shown in FIG. 6, the locate pin 3 is a columnar member, the tip end 31 of which is formed into a conical shape, and the lower end of which is provided with a collar 32. An attachment portion 33 is formed in the central axis direction of. Then, the locating pin 3 is fixed to the post 6 by the mounting portion 33. By the way, although ceramics are suitable as the material of the locate pin 3 from the viewpoint of heat resistance, heat insulation, etc., if the locate pin 3 having the mounting portion 33 as shown in FIG. 6 is integrally formed by using only the ceramic member. Since the width of the mounting portion 33 is suddenly smaller than the outer diameter of the collar 32, when a large force acts on the locate pin 3 when the locate pin 3 is used as an assembly jig, the collar 32 and the mounting portion 33 are not affected. There is a risk that stress concentration will occur at the boundary portion between and and the locate pin 3 will be damaged at the boundary portion. Therefore, while using a ceramic member having excellent heat resistance and heat insulation, even if stress concentration occurs at the boundary between the collar 32 and the mounting portion 33, the locate pin 3 is not damaged at the boundary. It is conceivable to use the locate pin 3.

Specifically, a ceramic member is used as a cylindrical member having a tip 31 formed in a conical shape and a flange 32 formed at the lower end, and is formed in the central axis direction of the flange 32. A metal member may be used for the attachment portion 33, and the joining structure of both members may be the above-described joining structure of the ceramic member and the metal member. That is, the ceramic member exhibits heat resistance against heat during welding, and the metal member withstands large stress concentration acting on the boundary portion between the collar 32 and the mounting portion 33 with high strength. A large force acts on 3 and the tsuba 32
Even if stress is concentrated at the boundary between the mounting portion 33 and the mounting portion 33, the locate pin 3 is not damaged at the boundary.

As described above, by using the ceramic / metal bonded body integrated by the bonding structure of the ceramic member and the metal member of this embodiment for the locate pin 3 of the assembly jig of the vehicle body, it is most suitable as the positioning pin. You can get a pin. The ceramic-metal joint structure of the present invention is not particularly limited as long as it is a joint between a ceramic member and a metal member, and can be applied to any parts, products, etc. As a typical application example, a projection nut is used. There are electrodes, etc.

[0018]

According to the present invention, there is no risk of the ceramic member cracking at high temperatures, and the metal member does not fall out of the tapered hole of the ceramic member at low temperatures. A solid and highly reliable joint structure can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a joined body of a ceramic member and a metal member according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a ceramic member of a joined body of the ceramic member and the metal member in FIG.

FIG. 3 is a plan view of a slit formed on a convex portion of a metal member of the joined body of the ceramic member and the metal member in FIG.

FIG. 4 is an enlarged cross-sectional view of a metal member of a joined body of the ceramic member and the metal member in FIG.

FIG. 5 is an explanatory view of a usage state of a vehicle body assembly jig.

FIG. 6 is a front view of a locate pin used for a vehicle body assembly jig.

[Explanation of symbols]

A Ceramics-metal bonded body 1 Ceramics member 2 Metal member 11 Tapered hole 21 Convex portion 22 Slot

Claims (2)

[Claims] 1. A joining structure of a ceramic member and a metal member having different coefficients of thermal expansion, wherein a tapered hole is formed in the ceramic member, the inner diameter of which gradually increases from the inlet to the back.
The metal member is formed such that the outer diameter is gradually increased from the lower end portion toward the front end portion, and a convex portion having a slit formed in the central axis direction is formed, and the metal member is formed in a taper hole of the ceramic member. A joint structure of a ceramic member and a metal member, characterized in that projections are fitted together. 2. A ceramic / metal structure characterized in that both members are integrated by fitting a convex portion formed on a metal member into a tapered hole formed on the ceramic member by the joining structure according to claim 1. Zygote.