JPH03197370A - Method for electrically joining ceramic hollow members to each other - Google Patents

Abstract

PURPOSE:To improve the cost and safety of the subject method by connecting ceramic hollow members to each other with a binder, disposing an inside electrode and an outside electrode on the inner and outer peripheral sides of the connected portion, respectively, and subsequently transferring either of the electrodes along the periphery of the connected portion. CONSTITUTION:Ceramic hollow members 1a, 1b are connected each other with a binder 2, and an inside electrode 4 and outside electrodes 5a, 5b are disposed on the inner and outer peripheral sides of the connected portion, respectively. Either of the electrodes is transferred along the periphery of the connected portion or the hollow members 1a, 1b are axially rotated to transfer the flow region of heating electric current (6a, 6b are electric sources) along the peripheral of the connected portion, the electric current being flowed between the inside electrode 4 and the outer electrodes 5a, 5b through the hollow members 1a, 1b or the binder 2, whereby the connected portion is wholly heated and joined.

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a method for electrically joining ceramic hollow members to each other. <Prior art and problems to be solved by the invention> As a method for joining ceramic hollow members, the members to be joined are butted with a bonding agent interposed between them, and a pair of electrodes is arranged on the outer diameter side of the hollow member. However, by passing an electric current between the electrodes through the hollow member or the bonding agent, the abutting portions were heated and bonded using the Joule heat generated in the hollow member or the bonding agent, but this method As the outer diameter becomes larger or the thickness becomes thicker, the required voltage value increases accordingly, and the electrical insulation of the equipment must be improved, which poses problems in terms of cost and safety. Means for Solving the Problems> In order to solve the above problems, in the present invention, an inner conductive member and an outer conductive member are disposed inside and outside of the abutting portion of ceramic hollow members, respectively, and the hollow The heating current flowing between the inner conductive member and the outer conductive member via the member is moved in the circumferential direction at the abutting portion, and the entire abutting portion is heated and joined. . Effects and Examples>

[Example 1] FIG. 1(a) and FIG. 1(b) are a schematic cross-sectional view and a vertical cross-sectional view, respectively, of an apparatus for carrying out the method of the present invention,
For example, round pipe-shaped ceramic hollow members 1a, l
This shows the case where the parts b are arranged in the vertical direction and joined. First, ceramic hollow members 1a, lb (φ60xφ4
CaF2. A paste-like bonding agent 2 made of kaolin is applied and dried, and the fixing jig 3a is stacked on top of each other.
, 3b. Next, an inner conductive member 4 and an outer conductive member 5a each having a rod shape, for example, are used for passing a heating current into and out of the ceramic hollow members 1a and lb. 5b are arranged facing each other with a gap of about one fin from the abutting portions, and power supplies 6a and 6b are connected between the outer conductive members 5a and 5b and the inner conductive member 4, respectively. Further, a gas burner 7a for heating the vicinity of the abutting portion,
7b is attached to the outer conductive members 5a, 5b. These outer conductive members 5m, 5b, inner conductive member 4 and gas burner 7
a, 7b can rotate around the axes of the ceramic hollow members 1a, lb. Now, the bonding atmosphere is set to the atmosphere, and the outer conductive members 5m and 5b, the inner conductive member 4, and the gas burner 7a are connected. 7b around the axis of the ceramic hollow member by 1109rp
By preheating the entire circumference near the abutting portion to approximately 800° C. with a gas burner while rotating at a rotational speed of A voltage of about 2,000 V is applied by the power sources 6g and 6b, and a heating current of 0.8 A is applied to the bonding agent 2, and the joules generated are The entire area near the abutting surfaces was heated to cause the bonding agent to react with the ceramics, and then cooled to room temperature to complete the bonding. From this sample 3X4X40
As a result of cutting out a specimen of the fin and conducting a 4-point bending test, the result was 300
The bending strength was M Pa. Note that the starting voltage for energization when the inner conductive member was not provided was approximately 3700V. [Example 2] FIG. 12(a) and FIG. 2(b) are a schematic cross-sectional view and a longitudinal cross-sectional view of an apparatus for carrying out the method of the present invention, respectively,
First, the resistivity is about 10-1Ω/Japanese SiC ceramics.
On the butt surface of a, lb (φ40 x φ24 x 30),
A bonding agent 2 of Ge powder was applied, and these were overlapped and fixed to fixing jigs 3g and 3b. Next, four outer conductive members 5c and 5d are formed from parts having substantially the same shape as the shape along the outer periphery of the ceramic member.
, 5e, 5f and the disk-shaped inner conductive member 41 are brought into contact with each other by applying carbon paste to the abutting portions of the ceramics, respectively, to connect the switching terminals 8g, 8b, 8c, 8 of the power source 6.
d and the outer conductive members 5c, 5d, 5e, and 5f, respectively, and the inner conductive member 41 and the ground terminal 8e of the power source 6 are connected. The power supply 6 has four output terminals 8a, 8b, 8
It has a function of sequentially applying voltage to c and 8d at arbitrary time intervals. Now, the bonding atmosphere is set to vacuum, and a voltage of about 36V is applied to the ceramic member from room temperature without preheating from the power supply 6.
Mainly energizes the vicinity of the butt part of the SIC ceramics, and switches the output terminals at a switching speed of 1/60 sec, changing the energization area to 5c → ceramic member → 41,5
By setting d→ceramic member→41,5e→ceramic member→41.5f→ceramic member→41, the energization position is moved intermittently and sequentially over the entire circumference of the abutting surfaces of the ceramics. The current was gradually increased from the start of energization until it reached 10°C at about 1200°C.
After holding for a minute, the current was gradually reduced and the bonding was completed by cooling to room temperature. Joint strength is 120MP in room temperature bending test
It was a. Note that the starting voltage for energization when the inner conductive member was not provided was approximately 110V. [Example 3] FIG. 3 is a schematic cross-sectional view of an apparatus for carrying out the method of the present invention, in which StC ceramics la is used. lb, bonding agent 2. Inner conductive member 41. Outer conductive member 5c
, 5d, 5e, 5f, and a power source 6. Outer conductive member 5c, output terminal 3a of power supply 6, outer conductive member 5
d and the output terminal 8b of the power source 6, and the outer conductive members 5e and 5f are connected to the ground terminal 8e of the power source 6, respectively. When a voltage is applied alternately to the two terminals 8a and 8b at an arbitrary time interval, the current-carrying area is 5c→ceramic member→inner conductive member 41−ceramic member=5e and 5d−ceramic member→inner conductive member 41→ceramic Part → 5f
and alternately. Therefore, the current supply position can be moved intermittently over the entire circumference of the abutting surfaces of the ceramics. Other bonding conditions are the same as in Example 2. The numbers of inner and outer conductive members shown in Examples 1 to 3 above are examples, and are not limited to the examples.
An appropriate number may be provided. Further, in the above-mentioned conductive member shown in Example 1, either the outer conductive member or the inner conductive member may rotate, and the non-rotating conductive member may have a shape extending over the entire circumference of the joint. . Alternatively, the conductive member and the ceramic may be brought into contact with each other without providing a gap between them. <Effects of the Invention> As described above, according to the present invention, by providing the inner conductive member, ceramics can be electrically bonded at a lower voltage than when the conductive member is provided only on the outside.

[Brief explanation of drawings]

FIG. 1(a) and FIG. 1(b) are a schematic cross-sectional view and a longitudinal cross-sectional view, respectively, of an apparatus for carrying out the method of the present invention. FIGS. 2 and 3 are schematic diagrams showing other examples of devices for carrying out the method of the present invention, respectively, in which a conductive member is fixedly disposed and a current-carrying area is changed in the circumferential direction by switching a switch. It moves and heats the area near the butt part to join. Figure 4 (a
) and FIG. 4(b) are a schematic cross-sectional view and a longitudinal cross-sectional view, respectively, of a conventional device. la, lb... Ceramic hollow member. 2... Bonding agent 4... Inner conductive member. 5a, 5b...Outer conductive member Figure 2 (a) Agent: Patent Attorney Naka Ihiro Procedural Amendment (self-motivated) October 26, 1990, 1999 Patent Application No. 279416 2, Name of the invention: Electrical joining method between ceramic hollow members 3, relationship with the amended person case

Claims (1)

[Claims] A bonding agent is interposed between ceramic hollow members, and an inner conductive member and an outer conductive member are disposed inside and outside of the abutted portion, respectively, and between the inner conductive member and the outer conductive member via the hollow member. A method for electrically joining ceramic hollow members together by heating the entire abutting portion while moving the energization position of a heating current applied to the abutting portion in the circumferential direction at the abutting portion.