JPH059085A - Method for joining ceramic member and metal member - Google Patents

Abstract

(57) [Summary] [Purpose] Even when the melting point of the filled metal material is higher than the precipitation hardening temperature, the bonding strength does not decrease and high bonding strength is maintained, and the ceramic member or metal member constituting the bonded body is damaged. In addition, it is possible to obtain a joined body of a ceramic member and a metal member which is excellent in durability and can be continuously used for a long time especially in a high temperature oxidizing atmosphere. [Structure] Filled metal material 5 having a melting point above the precipitation hardening temperature
Is melt-filled between the joint portion 2 of the ceramic member 1 and the recess 4 of the metal member 3 which has been subjected to the solution treatment before fitting, and the filling metal material 5 is solidified during the subsequent cooling process. The joint 2 and the recess 4 are joined, and the precipitation hardening treatment during the subsequent cooling process causes the precipitation hardening of the metal member 2 to obtain the high temperature strength required for joining the joint, and the joining 2 and the recess 4 are joined together. A shrinkage-fitting stress occurs due to heat shrinkage between them, increasing the joining force between them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining a ceramic member and a metal member, and more particularly to a method for joining a ceramic member and a metal member using a precipitation hardening alloy as the metal member. ..

[0002]

2. Description of the Related Art In recent years, mechanical parts used under high load and high temperature atmosphere in various industrial machinery have
Ceramic members having excellent corrosion resistance and wear resistance, high strength and small specific gravity have been widely used. However, since the above-mentioned ceramic member is poor in workability, the part where high temperature acts is composed of a ceramic member excellent in heat resistance, corrosion resistance, and wear resistance and having a small specific gravity, and the part where high load acts has high strength. A composite structure in which a ceramic member and a metal member are combined, such as a metal member having excellent properties, has attracted attention, and various methods of joining the ceramic member and the metal member have been studied and proposed.

For example, in Japanese Unexamined Patent Publication (Kokai) No. 3-69570, a precipitation hardening alloy is used as a metal member, and a ceramic member is joined to the metal member via a filling metal material during a cooling process after a melt filling process. Discloses a method of carrying out a treatment for precipitating and hardening the metal member while keeping it cooled in a furnace.

[0004]

However, in the method for joining the ceramic member and the metal member, the material metal is generally subjected to solution treatment before machining, and the recess is formed in the material metal by machining. Things as metal members,
During the cooling process after the melt-filling process of joining the ceramic member to the metal member via the filled metal material, a process of precipitating and hardening the metal member by holding the furnace cold is performed.

Therefore, when a recess is formed in the metal member from a precipitation hardenable alloy material by machining, heat generation or distortion generated by the machining causes a solution treatment applied to the material metal before machining. The effect has been lost.

In the precipitation hardening type alloy in which the effect of the solution treatment is lost as described above, even if the precipitation hardening treatment is performed by keeping the furnace cold during the cooling process after the melt filling processing, It is said that the high temperature strength for generating a sufficient shrinkage fit stress in the fitting portion of the ceramic member and the metal member at the time of cooling is not obtained, the joining force between the ceramic member and the metal member is weak, and the joining is unstable. There were challenges.

[0007]

A method of joining a ceramic member and a metal member according to the present invention comprises a solution treatment step of forming a recess in a metal member made of a precipitation hardening alloy and then subjecting the metal member to solution treatment. A fitting step of fitting the joint part of the ceramic member into the recess of the metal member after the solution treatment through a filling metal material having a melting point higher than the precipitation hardening temperature of the precipitation hardening alloy, and the filling metal material Melt filling treatment step of heating the filling metal material above the melting point between the joint portion of the ceramic member and the concave portion of the metal member, and keeping the furnace cold during the cooling process after the melting filling treatment step. And a precipitation hardening treatment step of precipitation hardening the metal member forming the recess.

[0008]

The method for joining a ceramic member and a metal member of the present invention will be described in detail below. In the joining method of the present invention, first, after forming a concave portion of a metal member made of a precipitation hardening alloy by machining or the like, it is held in a vacuum or in an inert gas atmosphere at a predetermined temperature for a predetermined time or more, and then rapidly cooled. As a result, alteration and distortion due to heat generation during machining of the metal member are removed, and the effect of the precipitation hardening treatment step after the melt filling treatment, which is the final step of joining, is enhanced.

The precipitation hardening type alloy is not particularly limited, but Incoloy 903, 9 which is an iron-based alloy mainly containing nickel (Ni) and cobalt (Co).
04 and 909 can be preferably used.

Further, the solution treatment is performed at a solution treatment temperature of 95.
The range of 0 ° C. to 1050 ° C. is preferable, and if it is outside this range, insufficient solution treatment or grain growth is not desirable. On the other hand, in order to sufficiently obtain the effect of solution treatment, it is preferable that the holding time at the solution temperature is 10 minutes or more and 120 minutes or less. The cooling rate after the solution temperature is maintained is preferably 500 ° C. or more per hour for rapid cooling to prevent precipitation of other crystal phases.

Next, a joint portion of a ceramic member having the same shape, which is smaller than the internal dimension of the concave portion by several tens of μm, is formed in the concave portion of the metal member after the solution treatment, and a melting point higher than the precipitation hardening temperature of the precipitation hardening alloy. It is fitted through the filled metal material.

The ceramic member is not particularly limited, but silicon nitride, silicon carbide, zirconia, alumina, etc. can be preferably used.

The filling metal material has a melting point higher than the precipitation hardening temperature of the precipitation hardening alloy and lower than the melting point of the precipitation hardening alloy, for example, silver wax, palladium wax, copper wax and nickel wax. Such a filled metal material is used in the shape of a disc or ring formed by punching out a plate material of the material, or in the shape of winding a wire material of the material.

Further, the filling metal material is heated to a temperature equal to or higher than the melting point and melted, and the filling metal material is filled between the joint portion of the ceramic member and the concave portion of the metal member, and then the filling metal material is cooled. During the process, the solidification temperature is reached and the solidification is performed, and at the same time, the solid fitting is performed while cooling to normal temperature. The melt filling process can also be performed with a load applied so that the joint portion of the ceramic member and the concave portion of the metal member are in close contact with each other.

In the cooling process after the melt-filling process, the furnace is kept in a predetermined temperature range for a predetermined time or longer to precipitate and harden the concave portion of the metal member. As a result, the solute is hardened due to the precipitation of the solute from the supersaturated solid solution, and the high temperature strength necessary for joining the joined portion of the ceramic member is obtained. Furthermore, the shrinkage-fitting stress generated from the difference in shrinkage amount based on the difference in thermal expansion coefficient between the joint and the recess acts to increase the joint strength.

The precipitation hardening treatment temperature is preferably within ± 100 ° C. from the precipitation hardening temperature and the holding time is 10
If it is less than 5 minutes, sufficient precipitation strength cannot be obtained, so that sufficient bonding strength cannot be obtained, and even if it is held for a long time exceeding 300 minutes, there is no change in the bonding strength. Therefore, the holding time is preferably 10 minutes or more and 300 minutes or less.

The method for joining the ceramic member and the metal member of the present invention will be described in detail below with reference to specific examples. FIG. 1 is a sectional view in which a main part of a joined body of a ceramic rotor and a metal shaft joined by applying the joining method of a ceramic member and a metal member according to the present invention is partially broken. In FIG. 1, reference numeral 1 is a ceramic rotor which is a ceramic member in which a joint portion 2 is fitted in a recess 4 formed by joining a metal shaft 6 to a metal sleeve 3 which is a metal member made of a precipitation hardening alloy. The filling metal material 5 is melt-filled between the joint portion 2 of the member 1 and the metal sleeve 3 to form a joined body of the ceramic rotor and the metal shaft.

The ceramic rotor 1 is made of silicon nitride (S
i ₃ N ₄ ) as a main component and a silicon nitride sintered body containing yttria (Y ₂ O ₃ ) and tungsten oxide (WO ₃ ) as a sintering aid. It is formed in the center. On the other hand, the metal sleeve 3 is made of Incoloy 909 which is a precipitation hardening type alloy having a solution temperature of 980 ° C., and the metal sleeve 3 is attached to the metal sleeve 3.
Are joined to form the recess 4. The outer diameter of the joint portion 2 is 10.00 mm and the inner diameter of the metal sleeve 3 is 10.08.
It was ground to mm. Further, the inner peripheral surface of the metal sleeve 3 was nickel-plated in order to improve the wettability of the filled metal material 5 made of a silver solder of BAg-8 having a melting point of 780 ° C. to the metal sleeve 3.

First, the ground metal sleeve 3 is heated and held in a vacuum furnace at a temperature of 980 ° C. for T ₁ hour, that is, for 60 minutes under a heat treatment condition as shown in FIG. 2, and then argon is placed in the vacuum furnace. Introduce gas and use cooling fan for T ₂ hours,
That is, it was forcibly cooled to room temperature over about 110 minutes. Then, the inner peripheral surface of the metal sleeve 3 was plated with nickel to a thickness of about 10 μm.

The metal sleeve 3 is connected to the ceramic rotor 1
Then, a silver solder corresponding to the BAg-8 standard having a melting point of 780 ° C. is placed as the filling metal material 5 on the end face of the joining part 2. The assembly thus assembled was set with the silver brazing part upward, a load was applied so as to press the metal sleeve 3 against the joint part 2, and the temperature was set to 830 ° C. under the heat treatment conditions shown in FIG. 3 in a vacuum furnace. After being held for t ₁ hour, that is, 15 minutes, the filling metal material 5 was melted and filled between the joint portion 2 and the metal sleeve 3. Then, argon gas was introduced into the vacuum furnace, and a cooling fan was used for t ₂ hours, that is, 610 in 60 minutes.
After forcibly cooling to ℃ and holding at 610 ℃ for t ₃ hours, ie, 300 minutes, again using the cooling fan as above, t
_It was forcibly cooled to room temperature in ₄ hours, that is, 60 minutes.

In the cooling process, first, the filling metal material 5 is used.
When the temperature reaches a freezing point of 780 ° C. or lower, the melted filling metal material 5 is solidified and joins the joint 2 and the metal sleeve 3. Next, while the temperature is kept at 610 ° C., the metal sleeve 3 is hardened due to precipitation of solute from the supersaturated solid solution, and high temperature strength necessary for joining with the joint 2 is obtained. If the above-mentioned solution treatment is not applied to the metal sleeve 3 which has been ground, the sufficient bonding strength cannot be obtained.

After the ceramic rotor 1 and the metal sleeve 3 are joined as described above, the metal shaft 6 is electronically beam-welded to the end surface of the metal sleeve 3 and finished by machining to obtain the ceramic. A rotor-metal shaft joint was manufactured.

Regarding the joined body of the ceramic rotor and the metal shaft, the pull-out strength for pulling out the ceramic rotor 1 from the metal sleeve 3 integrated with the metal shaft 6 and the torsional strength by twisting the ceramic rotor 1 and the metal sleeve 3 in opposite directions. Was measured in an atmosphere of 500 ° C., it was found that the conventional bonded body not subjected to the solution treatment had a pulling strength of 5.0 kg /
less than mm ^2, torsional relative strength that is 3.6 kg / mm ² or less, 5.4~6.0kg / mm ² is抜強degree in assembly by bonding method of the present invention, the torsional strength is 3.7
It was confirmed that the bonding strength was improved to 4.0 kg / mm ² .

Further, as a result of conducting a high-temperature high-speed rotation test in which the temperature of the exhaust gas was 950 ° C. using the above-mentioned joined body, the conventional joined body was broken at 150,000 revolutions per minute, It was confirmed that the joined body produced by the joining method of the present invention did not break even at 200,000 revolutions per minute and was joined well.

[0025]

As described in detail above, in the method for joining a ceramic member and a metal member of the present invention, the filler metal material having a melting point equal to or higher than the precipitation hardening temperature is melted before being fitted to the joint portion of the ceramic member. Is melt-filled between the recessed portion of the metal member subjected to the oxidization treatment, the filling metal material is solidified in the subsequent cooling process to join the joint portion and the recessed portion, and the recessed portion is formed by the precipitation hardening treatment during the subsequent cooling process. The high temperature strength required for joining to the joint by precipitation hardening is obtained, and shrinkage stress due to heat shrinkage is generated between the joint and the recess, and the joining force between the two is increased. Even if the melting point of the material is higher than the precipitation hardening temperature, the bonding strength does not decrease, and the ceramic member or metal member that constitutes the bonded body with high bonding strength is not damaged and excellent in durability. Especially high temperature oxidizing atmosphere It is possible to obtain the bonded body of the ceramic member and the metal member is capable of long-time continuous use in air.

[Brief description of drawings]

FIG. 1 is a sectional view in which a main part of a joined body of a ceramic rotor and a metal shaft joined by applying a joining method of a ceramic member and a metal member according to the present invention is partially broken.

FIG. 2 is a diagram showing heat treatment conditions for solution treatment in the method for joining a ceramic member and a metal member according to the present invention.

FIG. 3 is a diagram showing heat treatment conditions for melt filling and precipitation hardening in the method for joining a ceramic member and a metal member according to the present invention.

[Explanation of symbols]

 1 Ceramic Member 2 Joined Part 3 Metal Member 4 Recessed 5 Filled Metal Material

Claims (1)

Claim: What is claimed is: 1. A solution treatment step of forming a recess in a metal member made of a precipitation hardening alloy and then solutionizing the metal member, and a recess in the metal member after the solution treatment. A fitting step of fitting the joint portion of the ceramic member through a filling metal material having a melting point higher than the precipitation hardening temperature of the precipitation hardening alloy, and heating the filling metal material to a melting point or higher to form the filling metal material. A melt-filling treatment step of melt-filling between the bonded portion of the ceramic member and the recess of the metal member, and precipitation hardening of the metal member forming the recess by keeping the furnace cold during the cooling process after the melt-filling treatment step. A method for joining a ceramic member and a metal member, which comprises a precipitation hardening treatment step of: