JPH07300374A - Joined structure of heat-shielding member and method for joining the same - Google Patents

Abstract

PURPOSE:To provide a joined structure of the heat-shielding members, secured in a joined strength in the joining of a porous ceramic to a fine ceramic, and to provide a method for joining the same. CONSTITUTION:In the joined structure of the heat-shielding member, a thin plate 3 comprising fine Si3N4 is placed between a porous Si3N4 member 2 having a porosity of <=1% and a fine Si3N4 member 1 having a porosity of <=1%. The porous Si3N4 member 2 and the thin plate 3 are joined to each other through an oxide 4 containing Ca-Si-O, and the thin plate 3 and the fine Si3N4. member 1 are joined to each other through a Ni-containing metal 5 with solid phase diffusion. A fused phase 6 is formed between the porous Si3N4 member 2 and the oxide 4, and a reaction layer 7 is formed between the oxide 4 and the thin plate 3. CrN layers 8,9 are formed between the thin plate 3 and the metal 5, and between the metal 5 and the fine Si3N4 member 1, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat shield member joining structure for joining porous ceramics and dense ceramics and a joining method thereof.

[0002]

2. Description of the Related Art Conventionally, when an adiabatic piston is made of a low heat conductive material, a method of spray coating a low heat conductive film such as a zirconia Zr ₂ O coating on the upper surface of the piston crown exposed to the combustion gas, or a high strength ceramics A low thermal conductive material separately prepared is placed on the upper surface, and the two are chemically bonded together.

Further, as a joining method for joining Si ₃ N ₄ ceramics to each other to secure the strength of the joined portion even at a high temperature of 600 to 800 ° C., oxidation is carried out by using a CaO--SiO ₂ system glass solder. There is already known a solid soldering method or a solid phase bonding method in which a high melting point oxidation resistant metal such as Ni—Cr is interposed, and components are diffused by heating under pressure to form a reaction layer.

Further, Japanese Patent Laid-Open No. 3-193675 discloses a method for electrically connecting ceramics. The ceramic electrical joining method is an electrical joining method between a ceramic and a metal or between ceramics, and an electrical joining insert material including insulating ceramics in which a heating element is buried between members to be joined except for a current-carrying terminal is provided. By abutting and abutting and passing a current between the energizing terminals, Joule heat generated in the heating element directly heats and abuts the abutting portion and its vicinity.

Further, Japanese Patent Application Laid-Open No. 3-295868 discloses a method of controlling the output of a power supply for electric connection of ceramics. The publication discloses that the abutting portions of the ceramics are electrically heated and joined together.
CaO / as a bonding agent when bonding iC ceramics
It is disclosed to use an oxide solder mainly composed of SiO ₂ / Al ₂ O ₃ or a thin plate of Cu—Ti alloy.

[0006]

However, in the ceramics gradient composition component, the one in which the ceramic member is coated with the low thermal conductive film has insufficient heat shielding property, and the high strength ceramics and the low thermal conductive material are chemically combined. The high strength ceramics and the low thermal conductive material may not be bonded to one of the two because they have different reactivities to the solder material. Moreover, since the high-strength ceramics and the low thermal conductive material are separately manufactured and processed, there are problems that the number of processing steps increases and the manufacturing cost also increases.

Further, reaction-sintered Si in which oxide is dispersed₃
N_FourHas already been developed to be a low heat conductive material,
The low heat conductive material is made of high strength Si.₃N_FourCombined with heat shield parts
In this case, there are advantages and disadvantages to the above joining method. Immediately
The above-mentioned bonding by the oxide solder method has a high bonding strength.
However, due to the high joining temperature of 1550 ° C,
Dense Si that is a bonded body₃N_FourRecrystallization etc. inside the group
Changes in composition occur and dense Si₃N_FourThe strength of itself is the original strength
The phenomenon of a decrease of about 250 MPa
is there. Further, in the joining by the solid phase joining method, Ni--C is used.
Porous Si has an affinity for Cr in r₃N_FourAnd precision
Si₃N_FourSince Cr is different,₃N _FourAgglomerate to the side
As a result, porous Si₃N_FourThe joint strength is extremely high without wetting the sides.
The phenomenon of becoming extremely low occurs.

[0008] Therefore, an object of the present invention is to solve the above-mentioned problems, and by taking advantage of the bonding between the oxide solder method and the solid-phase bonding method, porous ceramics and dense Si ₃ N _{4 are used.} Is strongly bonded to each other, and a thin plate of the dense Si ₃ N _{4 having} a thickness of about 0.5 mm, that is, a thin plate is interposed between the porous ceramic and the dense Si ₃ N ₄ to form a porous ceramic. Provided are a heat shield member joining structure and a joining method for joining a thin plate by an oxide solder method, a thin plate and a dense Si ₃ N ₄ by a solid phase joining method, and firmly joining the both as a whole. That is.

[0009]

In order to achieve the above object, the present invention is configured as follows. That is,
According to the present invention, a thin plate made of dense Si ₃ N ₄ is interposed between a porous ceramic member having a porosity of 15% or more and a dense Si ₃ N ₄ member having a porosity of 1% or less, The porous ceramic member and the thin plate are made of Ca-Si-O.
A bonding structure for a heat shield member, characterized in that the thin plate and the dense Si ₃ N ₄ member are bonded to each other by solid phase diffusion via a metal containing Ni, and are bonded via an oxide containing . Also, in the joint structure of this heat shield member,
A fusion phase is formed between the porous ceramic member and the Ca-Si-O-containing oxide, and the Ca-Si-
A reaction layer is formed between the oxide containing O and the thin plate, and C is formed between the thin plate and the metal containing Ni.
An rN layer is formed, and the metal containing Ni and the dense S
A CrN layer is formed between the i ₃ N ₄ member. In particular, the porous ceramic member is composed of a porous Si ₃ N ₄ member in which an oxide is dispersed.

Alternatively, according to the present invention, a porous ceramic member having a porosity of 15% or more and a dense Si having a porosity of 1% or less.
_A thin plate made of dense Si ₃ N ₄ is interposed between the ₃ N ₄ member, and the porous ceramic member and the thin plate are bonded via an oxide containing Ca—Si—O. The thin plate and the dense Si ₃ N ₄ member are bonded to each other by solid-phase diffusion through a metal containing Cu and Ti, and a bonding structure of a heat shield member. Further, in the joint structure of the heat shield member, a fusion phase is formed between the porous ceramic member and the oxide containing Ca-Si-O, and the oxide containing Ca-Si-O is formed. A reaction layer is formed between the thin plate and the thin plate and the C
A TiN layer is formed between the metal containing u and Ti, and a TiN layer is formed between the metal containing Cu and Ti and the dense Si ₃ N ₄ member. In particular,
The porous ceramic member is composed of a porous Si ₃ N ₄ member in which an oxide is dispersed.

Further, the joint structure of the heat shield member is such that a piston formed of the dense Si ₃ N ₄ member and a head portion which is formed of the porous ceramic member and is arranged on the combustion chamber side. It is preferably applied to a piston head composed of a head body attached to a skirt.

Alternatively, according to the present invention, a porous Si ₃ N ₄ member having a porosity of 15% or more and an oxide dispersed therein and a dense S.
A thin plate made of i ₃ N ₄ is bonded via an oxide containing Ca—Si—O, and then the thin plate and a dense Si ₃ N ₄ member having a porosity of 1% or less are contained in Ni-containing metal or Cu. , T
The present invention relates to a method for joining a heat shield member, characterized in that the members are joined by solid phase diffusion via a metal containing i.

[0013]

The joining structure of the heat shield member and the joining method according to the present invention are configured as described above, and act as follows. In the joint structure of this heat shield member, since the porous ceramic member having a porosity of 15% or more and the thin plate made of dense Si ₃ N ₄ are bonded via the oxide containing Ca—Si—O, Dense S when bonded to oxides or solder materials
Although the strength of the thin plate made of i ₃ N ₄ decreases, at that time, the thin plate itself has a strength of about 700 MPa, which is a sufficiently high level of strength as compared with the bonding strength.

However, when one of the objects to be joined is silicon nitride and the other is a porous material having different components,
When these are joined, the oxide solder method enables joining, but since the joining temperature is high, the strength of the article itself deteriorates. On the other hand, in the case of joining with a brazing material such as Cu-Ti or a joining material of Ni-Cr, each Ti or Cr must be uniformly aggregated on both sides in order to firmly join the objects to be joined. It becomes a condition. If the materials of the objects to be joined are different, the chemical affinities are different, so that Ti or Cr approaches only one object to be agglomerated,
A phenomenon occurs in which joining cannot be achieved. Therefore, in the present invention, when joining with a brazing material such as Cu-Ti or a joining material of Ni-Cr, the materials on both sides are dense Si ₃ N of the same material.
₄ are arranged and firmly joined.

The joint structure of the heat shield member has a strength of 200.
Porous Si ₃ N _{4 of} about MPa and dense Si ₃ N ₄ are bonded with high strength, and the strength of dense Si ₃ N ₄ is 900M.
The original strength of Pa to 1000 MPa is secured. Here, since the bonding strength does not exceed the strength of the porous ceramics, it is sufficient to secure the bonding strength equivalent to that of the porous ceramics. Basically, the oxide solder method of CaO-SiO ₂ system the object to be bonded,
Bonding can be ensured by bonding at a high temperature of 1550 ° C. or higher.

However, a drawback of the high temperature oxide soldering method is that the strength of the dense Si ₃ N ₄ itself, which is the object to be bonded, decreases by about 30%. In the joining structure of the heat shield member according to the present invention, the strength of the dense Si ₃ N ₄ thin plate that is the joining member of the porous ceramics is about 700 MPa.
Although it deteriorates to some extent, it is a sufficiently high level as compared with the bonding strength at the bonded portion, that is, the strength of the porous ceramics. Since the joining portion and the dense Si ₃ N ₄ member are joined at a joining temperature that does not cause deterioration of the joining strength by using a brazing material or Ni-Cr, the strength of the dense Si ₃ N ₄ is itself. Will be maintained. Further, in the joining using the active brazing material or the Ni-Cr joining material, it is preferable that the materials of the articles to be joined are as homogeneous as possible. Therefore, in the present invention, a thin plate made of dense Si ₃ N ₄ is used to be inserted between the objects to be joined.
On the other hand, in the prior art, it is difficult to raise the bonding temperature to 1550 ° C. or higher, so that a solder material having a relatively low melting point is used.

[0017]

Embodiments of a heat shield member joining structure and joining method according to the present invention will be described below. FIG. 1 is a sectional view showing an embodiment in which the joining structure of the heat shield member according to the present invention is applied to a piston head of a heat shield piston, and FIG. 2 is a diagram showing an embodiment of the joint structure of the heat shield member according to the present invention. It is an expanded sectional view of the code | symbol A part in 1. 1 and 2, the same reference numerals are given to the same members.

An embodiment of the joining structure of the heat shield member according to the present invention will be described with reference to FIG. As shown in FIG. 2, the bonding structure of the heat shield member comprises a porous ceramic member having a porosity of 15% or more and a dense silicon nitride member having a porosity of 1% or less, that is, a dense Si ₃ N ₄ member 1. Between the dense Si
_A thin plate 3 made of ₃ N ₄ is interposed. In this embodiment, the porous ceramic member is composed of a porous silicon nitride member, that is, a porous Si ₃ N ₄ member 2 in which an oxide is dispersed. The thin plate 3 has a thickness of, for example, about 0.5 mm. The porous Si ₃ N ₄ member 2 and the thin plate 3 are bonded via an oxide 4 containing Ca-Si-O, and the thin plate 3 and the dense Si ₃ N ₄ member 1 are made of a metal 5 containing Ni. Through solid phase diffusion. Furthermore, a fusion phase 6 is formed between the porous Si ₃ N ₄ member 2 and the oxide 4 containing Ca-Si-O, and Ca-Si-O is formed.
A reaction layer 7 is formed between the oxide 4 containing oxide and the thin plate 3. In addition, C is present between the thin plate 3 and the metal 5 containing Ni.
The rN layer 8 is formed, and the metal 5 containing Ni and the dense Si ₃
A CrN layer 9 is formed between the N ₄ member 1 and the N ₄ member 1.

The joining structure of the heat shield member according to the present invention is, for example, as shown in FIG. 1, a piston skirt made of a metal such as Al or cast iron which constitutes a heat shield piston reciprocating in a cylinder (see FIG. This is extremely preferable when applied to a ceramic piston head 15 fixed to (not shown). The piston head 15 has an annular shaft portion 16 that fits in a mounting hole formed in the center of the piston skirt.
It is composed of a head body 13 having The annular shaft portion 16 of the head body 13 is fitted in the mounting hole of the piston skirt, and the coupling ring is plastically deformed by metal flow or the like to fix the piston head 15 to the piston skirt. Further, the head body 13 has a cylindrical portion 17 in the periphery,
A heat shield member made of a material having a low thermal conductivity is arranged in the space 14 formed by the cylindrical portion 17, that is, on the combustion chamber side. Since the heat shield member is located on the side exposed to the combustion gas, a dense Si ₃ N ₄ thin film is formed on the surface exposed to the combustion gas in order to prevent combustion gas, fuel, etc. from entering the heat shield member. 18 is coated. In such a piston head 15,
The head body 13 is made of the dense Si ₃ N ₄ member 1,
The heat shield member is made of a porous Si ₃ N ₄ member 2, and the heat shield member is joined to the head body 13. Therefore, the porous Si ₃ N ₄ member 2 forming the heat shield member in the piston head 15 is firmly bonded to the dense Si ₃ N ₄ member 1 forming the head body 13.

Next, a method of joining the heat shield members according to the present invention will be described. The method of joining the heat shield members has a porosity of 15
%, The porous Si ₃ N ₄ member 2, which is a porous ceramic member in which oxides are dispersed, and the thin plate 3 made of dense Si ₃ N ₄ are bonded via the oxide 4 containing Ca-Si-O. Then, the thin plate 3 and the dense Si ₃ having a porosity of 1% or less
N ₄ member 1 and Ni-containing metal 5 (see FIG. 2) or C
It is bonded by solid phase diffusion through the metal 10 containing u and Ti (see FIG. 3).

Therefore, a process of producing the joint structure of the heat shield member will be described. In this method of joining the heat shield members, Si: 65 wt%, Ti: 10 wt%, Al ₆ Si
_A mixed powder of ₂ O ₁₃ (mullite); 25 wt% was used as a raw material to form a disk-shaped compact of φ90 × thickness 14. This molded body was subjected to reaction sintering in a N ₂ atmosphere at 1450 ° C. to produce a reaction sintered body. This reaction sintered body is 1000
Oxidation treatment was performed at 20 ° C. for 20 hours to produce a porous Si ₃ N ₄ sintered body. This porous Si ₃ N ₄ sintered body was processed and polished to a predetermined size to prepare a plate-shaped porous Si ₃ N ₄ member 2 of φ80 × 11 mm.

Next, a mixed powder of CaO--SiO ₂ --Si ₃ N ₄ was heated to 1600 ° C. and then rapidly cooled in water at 20 ° C. to prepare glass. After crushing this glass, the crushed glass was classified to prepare glass powder. Next, the glass powder was melted with polyvinyl alcohol PVA to form a paste. Therefore, the paste-like material was applied to the bonding surface of the porous Si ₃ N ₄ member 2 produced above. A dense Si ₃ N ₄ having a diameter of 82 mm and a thickness of 0.5 mm is formed on the joint surface of the porous Si ₃ N ₄ member 2 coated with the paste material.
The thin plate 3 consisting of was laminated and adhered by applying a load of 500 kg. Next, the thin plate 3 is adhered to the porous Si ₃ N ₄ member 2 with the paste-like material interposed therebetween, and after degreasing, the porous Si ₃ N ₄ member 2 is heated at 1550 ° C. in an N ₂ atmosphere. And the thin plate 3 were joined.

On the other hand, the surface of the dense Si ₃ N ₄ member 1 was polished by a grindstone of mesh # 1000 to remove about 100 μm, and then the polished surface was porous with Ni-Cr having a thickness of 0.1 mm interposed. The thin plate 3 bonded to the Si ₃ N ₄ member 2 was superposed and bonded in a vacuum at 1200 ° C. As described above, the dense Si ₃ N ₄ member 1 and the porous Si ₃ N ₄ member 2 were bonded with the thin plate 3 interposed.

Next, the dense Si ₃ N ₄ member 1 and the porous S
When the structure near the joint with the i ₃ N ₄ member 2 was analyzed and the joint strength at 600 ° C. was evaluated, it was as follows. At the bonding interface between the porous Si ₃ N ₄ member 2 and the thin plate 3, Ca diffuses to the porous Si ₃ N ₄ member 2 side,
The fused phase 6 was formed and firmly bonded. Further, the same analysis was performed on the portion where the dense Si ₃ N ₄ member 1 and the thin plate 3 were bonded by Ni—Cr, and the dense S
Since the i ₃ N ₄ member 1 and the thin plate 3 are made of the same quality of Si ₃ N ₄ , the Cr component was agglomerated on both Si ₃ N ₄ sides and changed to CrN at the joint portion. Thermal expansion coefficient CTE of CrN about 7.0 × 10 ^- was ⁶ / ° C., the value is substantially intermediate value between the thermal expansion coefficient the top of the Si ₃ N ₄ and Ni, the thermal expansion coefficient of inclined manner It can be seen that the thermal stress is relieved because they are joined.

The porous Si ₃ N ₄ member and the dense Si
_{When the 3} N ₄ member was used as the article to be joined and joined by two methods, the joining strength at 600 ° C. of the joined parts of both the articles was measured. One bonding method was by the CaO—SiO ₂ oxide solder method, and the bonding temperature was 1550 ° C. The other joining method was a solid-state joining method using Ni-Cr, and the joining temperature was 1200 ° C. In addition, the porous Si ₃ N ₄ member and dense Si ₃ N
The strength of each of the members to be bonded when the members to be bonded to the _four members themselves were heat-treated at temperatures of 1550 ° C. and 1200 ° C. was measured. The results were as follows.

That is, in the case of CaO-SiO ₂ bonding by the oxide solder method, porous Si ₃ N ₄ and dense Si ₃ N are used.
Average 4-point flexural bond strength between ₄ (MPa), the temperature 600
It was 192 MPa in the atmosphere of ° C. The strength of the porous Si ₃ N ₄ after heat treatment is 190 MPa,
The strength of the dense Si ₃ N ₄ was 720 MPa, which was confirmed to be about 250 MPa lower than the strength of the dense Si ₃ N ₄ before the heat treatment (original). Further, in the joining by solid phase bonding method by Ni-Cr, an average four point flexural bonding strength between the porous Si ₃ N ₄ and dense Si ₃ N ₄ (MPa)
Was 45 MPa in an atmosphere at a temperature of 600 ° C. Strength of porous Si ₃ N ₄ after heat treatment is 188 MPa
And the strength of the dense Si ₃ N ₄ was 978 MPa.

From these measurement results, CaO-SiO ₂
It was found that in the joining by the oxide solder method of 1), the joining strength was high, but the strength of the dense Si ₃ N ₄ was significantly deteriorated due to the influence of the heat treatment. Moreover, in the joining by the solid-state joining method using Ni-Cr, since the heat treatment temperature is lower than that in the oxide solder method, it is not affected by heat, but the porous S
It was found that the bonding strength between i ₃ N ₄ and dense Si ₃ N ₄ was extremely low.

Next, the 2-stage bonding by the bonding method of the heat shield according to the invention, consisting of dense Si ₃ N ₄ between the porous Si ₃ N ₄ member 2 and the dense Si ₃ N ₄ member 1 Bonding was performed with the thin plate 3 interposed, and ten bonded samples were prepared. That is, the porous Si ₃ N ₄ member 2 and the thin plate 3 are joined by the oxide solder method, and then the dense Si ₃ N ₄ member 1 is joined.
The thin plate 3 and the thin plate 3 were joined by a solid-state joining method. The bonding strength of these bonded samples in the atmosphere of 600 ° C. was measured, and the results are shown in Table 1.

[Table 1]

As can be seen from Table 1, porous Si ₃ N ₄
The bonding strength between the member 2 and the dense Si ₃ N ₄ member 1 is almost the same as the strength of the porous Si ₃ N ₄ , that is, the average bonding strength is 194 MPa, and the fracture position is not limited to the bonded portion, Some fractured at the porous Si ₃ N ₄ part.

Next, another embodiment of the joining structure of the heat shield member according to the present invention will be described with reference to FIG. FIG. 3 is an enlarged sectional view of a portion A in FIG. 1 showing another embodiment of the heat shield member joining structure according to the present invention. In FIG. 3, FIG.
The same members as the members shown in FIG.

As shown in FIG. 3, the joint structure of the heat shield member has a porous Si ₃ N ₄ member 2 which is a porous ceramic member having a porosity of 15% or more and a dense material having a porosity of 1% or less. A thin plate 3 made of dense Si ₃ N ₄ is interposed between the thin plate 3 and the Si ₃ N ₄ member 1. In this example, the porous ceramic member is a porous Si ₃ N having oxide dispersed therein.
It is composed of _four members 2. The thin plate 3 has a thickness of, for example, about 0.5 mm. Porous Si ₃ N
₄ Member 2 and thin plate 3 are bonded via oxide 4 containing Ca-Si-O, and thin plate 3 and dense Si ₃ N ₄ member 1 are solid-phase diffused via metal 10 containing Cu and Ti. Are combined by. Porous Si ₃ N ₄ member 2 and Ca-Si-O
The fusion phase 6 is formed between the oxide 4 and the
A reaction layer 7 is formed between the oxide 4 containing Si—O and the thin plate 3. Further, a TiN layer 11 is formed between the thin plate 3 and the metal 10 containing Cu and Ti, and Ti is formed between the metal 10 containing Cu and Ti and the dense Si ₃ N ₄ member 1.
The N layer 12 is formed.

That is, this embodiment is different from the above embodiment in that the metal 1 containing Cu and Ti instead of the metal 5 containing Ni is used.
The bonding method is exactly the same except that the thin plate 3 and the dense Si ₃ N ₄ member 1 are bonded using 0. The bonding mechanism according to this embodiment is similar to that of the above embodiment,
By configuring the object to be bonded with the sheet 3 dense Si ₃ N ₄ and dense Si ₃ N ₄ member 1 in dense Si ₃ N ₄ of the same type, homogeneous, the active ingredient Ti is both object to be bonded It was confirmed that as a result of diffusing into, it is possible to secure high bonding strength.

[0033]

Since the heat shield member joining structure and the joining method according to the present invention are configured as described above, they have the following effects. In the joint structure of the heat shield member, a thin plate made of dense Si ₃ N ₄ is interposed between the porous ceramic member and the dense Si ₃ N ₄ member, and the porous ceramic member and the thin plate are joined together. is bonded via an oxide containing Ca-Si-O, the said thin dense Si ₃ N ₄
Since the member is bonded by solid phase diffusion through a metal containing Ni or a metal containing Cu or Ti, the dense S
It is possible to secure stable bonding strength at least equivalent to that of the porous ceramic member without deteriorating the original strength of the i ₃ N ₄ member.

Therefore, this structure for joining the heat shield members has a porous ceramic member when the engine component, particularly the piston head, is made of a low heat conductive porous ceramic member and a high-strength dense Si ₃ N ₄ member. This is an extremely preferable one because it is possible to secure a stable bonding strength by bonding with the dense Si ₃ N ₄ member.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment in which a heat shield member joining structure according to the present invention is applied to a piston head of a heat shield piston.

FIG. 2 is an enlarged cross-sectional view of a portion A in FIG. 1 showing an embodiment of a heat shield member joining structure according to the present invention.

FIG. 3 is an enlarged cross-sectional view of a portion A in FIG. 1 showing another embodiment of the heat shield member joining structure according to the present invention.

[Explanation of Codes] 1 dense Si ₃ N ₄ member 2 porous Si ₃ N ₄ member 3 dense Si ₃ N ₄ thin plate 4 oxide containing Ca—Si—O 5 metal containing Ni 6 fusion phase 7 Reaction layer 8,9 CrN layer 10 Metal containing Cu and Ti 11,12 TiN layer 13 Head body 14 Vacancy 15 Piston head

Claims (7)

[Claims] 1. A thin plate made of dense Si ₃ N ₄ is interposed between a porous ceramic member having a porosity of 15% or more and a dense Si ₃ N ₄ member having a porosity of 1% or less. ,
The porous ceramic member and the thin plate are made of Ca-Si-
Bonding of a heat shield member, characterized in that the thin plate and the dense Si ₃ N ₄ member are bonded to each other via an oxide containing O, and are bonded by a solid phase diffusion via a metal containing Ni. Construction. 2. The porous Si ₃ N ₄ member and the Ca-
A fusion phase is formed between the oxide containing Si-O, a reaction layer is formed between the oxide containing Ca-Si-O and the thin plate, and the thin plate and the Ni are formed. The CrN layer is formed between the metal containing Ni and the CrN layer is formed between the metal containing Ni and the dense Si ₃ N ₄ member. Bonding structure of heat shield members. 3. A thin plate made of dense Si ₃ N ₄ is interposed between a porous ceramic member having a porosity of 15% or more and a dense Si ₃ N ₄ member having a porosity of 1% or less. ,
The porous ceramic member and the thin plate are made of Ca-Si-
A heat shield member, characterized in that the thin plate and the dense Si ₃ N ₄ member are bonded by an oxide containing O, and are bonded by solid phase diffusion through a metal containing Cu and Ti. Junction structure. 4. The porous ceramic member and the Ca-
A fusion phase is formed between the oxide containing Si-O, a reaction layer is formed between the oxide containing Ca-Si-O and the thin plate, and the thin plate and the Cu are formed. , A TiN layer is formed between the metal containing Ti and Cu, Ti
Ti between the metal containing Ti and the dense Si ₃ N ₄ member.
The heat shield member joining structure according to claim 3, wherein an N layer is formed. 5. A head portion formed of the porous ceramic member and forming a surface arranged on the combustion chamber side, and a head main body attached to a piston skirt formed of the dense Si ₃ N ₄ member. It is applied to a piston head, The joining structure of the heat-shielding member in any one of Claims 1-4 characterized by the above-mentioned. 6. The joint structure for a heat shield member according to claim 1, wherein the porous ceramic member is a porous silicon nitride in which an oxide is dispersed. 7. A porous ceramic member having a porosity of 15% or more and in which an oxide is dispersed, and a thin plate made of dense Si ₃ N ₄ are bonded via an oxide containing Ca—Si—O, and then, A method for joining a heat shield member, characterized in that the thin plate and a dense Si ₃ N ₄ member having a porosity of 1% or less are joined by solid phase diffusion through a metal containing Ni or a metal containing Cu or Ti. .