JP2006196315A - Aggregate of ceramics and metal, and fuel cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve sealing performance and reinforce a sealing structure. <P>SOLUTION: The aggregate of ceramics and metal is provided with a ceramic tube 1, a metal plate 2, and a sealing structure 3 linking the ceramic tube (1) and the metal plate 2. The sealing structure 3 consists of a sealing layer 5, intercalated between the ceramic tube 1 and the metal plate 2, a first ring 4, intercalated between the sealing layer 5 and the metal plate 2, and a second ring 11 as a part of the metal plate 2, intercalated between the first ring 4 and the metal plate 2. The sealing layer 5 has an adhesive force toward the ceramic tube 1 and the first ring 4. The second ring 11 has a curved surface 7 smoothly bent in a center line L direction L of the ceramic tube 1. The curved surface 7 is in planar contact or linear contact with respect to the first ring 4 in terms of pressure. The curved surface 7 is formed by bending the metal plate 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a combined body of ceramics and metal and a fuel cell module, and more particularly to a combined body of ceramics and metal having a cylindrical structure and a fuel cell module.

  Research is underway to improve the efficiency of fuel cells. For example, research is being conducted to reduce the size of the fuel cell module and increase the power density per unit volume. The fuel cell module is formed of a combination of a ceramic fuel cell tube including a plurality of fuel cells and a metal plate. Bonding metal and ceramics is difficult. In particular, it is difficult to bond to guarantee the sealing performance between them. As shown in FIG. 16, the combined body includes a disc 101 that is a metal tube plate that holds a fuel cell tube, and a large number of fuels that are inserted through the disc 101 in the tube axis direction. And a battery cell tube 102. A seal structure is interposed between the disc 101 and the fuel cell tube 102. It is important that the seal structure 103 is sufficiently satisfactory in terms of both sealing performance and bonding strength. The seal structure 103 constitutes a seal ring 104 interposed between the disc 101 and the fuel cell tube 102. An adhesive bonding material 105 is used between the seal ring 104 and the fuel cell tube 102. The disc 101 and the seal ring 104 are joined by the first joining surface 106 and the second joining surface 107.

  The disk 101 and the ceramic tube 102 are heated to several hundred degrees or more. Since the extending directions of many fuel battery cell tubes 102 are not aligned, it is conceivable that a mismatching force is applied to the disc 101. In that case, if the gas used on the upper and lower sides of the disc 101 is different, it is considered that the used gas leaks between the upper and lower sides of the disc 101. The used gas permeates and leaks through the first joint surface 106 and the second joint surface 107 and further leaks through the adhesive joint material 105. It is conceivable that the thermal deformation caused by the high temperature causes deterioration in the adhesion performance between the first joint surface 106 and the second joint surface 107. As the adhesive bonding material 105, an inorganic adhesive is used to improve the strength. An inorganic adhesive layer formed of an inorganic adhesive may be formed in a porous shape. At that time, the permeability to the gas used becomes strong.

  Improvement in sealing performance is required. Furthermore, the sealing structure is required to be strengthened. The durability and long life of the seal structure are desired.

JP 2003-308854 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a ceramic / metal combination and a fuel cell module capable of reducing a factor of lowering the efficiency of the fuel cell at the joint between the fuel cell tube and the metal.

  Another object of the present invention is to provide a combined body of a ceramic and a metal and a fuel cell module capable of improving the sealing performance at the joint portion between the fuel battery cell tube and the metal.

  Still another object of the present invention is to provide a ceramic / metal combination and a fuel cell module that can reinforce the seal structure at the joint between the fuel cell tube and the metal.

  Another object of the present invention is to provide a ceramic / metal combination and a fuel cell module capable of improving the durability and life of the seal structure at the joint between the fuel cell tube and the metal.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the best mode for carrying out the invention. These numbers and symbols are added in parentheses in order to clarify the correspondence between the description of the claims and the best mode for carrying out the invention. However, these numbers and symbols should not be used for interpreting the technical scope of the invention described in the claims.

In order to solve the above-mentioned problems, a ceramic / metal bonded body according to the present invention includes a ceramic tube (1), a metal plate (2), and a seal structure for bonding the ceramic tube (1) and the metal plate (2). (3). The seal structure (3) includes a seal layer (5) interposed between the ceramic tube (1) and the metal plate (2), and is interposed between the seal layer (5) and the metal plate (2). And a second ring (11) that is a part of the metal plate (2) and is interposed between the first ring (4) and the metal plate (2). . The sealing layer (5) is adhesive to the ceramic tube (1) and the first ring (4). The second ring (11) has a curved surface (7) that bends smoothly in the direction of the center line (L) of the ceramic tube (1). The curved surface (7) is in pressure surface contact or line contact with the first ring (4). The curved surface (7) is formed by bending the metal plate (2).
The second ring (11) is press-fitted to the first ring (4). The second ring (11) to be joined is formed elastically. Bonding between the first ring (4) and the second ring (11) has good adhesion. The composite of a plurality of ceramic tubes and metal plates is susceptible to stress in a direction parallel to the surface of the metal plate due to temperature change, but the sealing structure of the ceramic-metal combination according to the present invention is such a lateral direction. In particular, it has a strong resistance force against the stress of and can satisfactorily guarantee both the seal structure and the strength structure.

  In the combination of ceramics and metal, the curved surface (7) is formed substantially symmetrical with respect to the center line (L).

  In the combination of ceramics and metal, the curved surface (7) is a convex curved surface toward the center line (L).

  In the combination of ceramics and metal, the first ring (4) is a metal cylinder.

  In the ceramic / metal combination, the ceramic tube (1) is filled with fuel gas or oxidant gas for the fuel cell.

  In the composite body of ceramics and metal, the ceramic tube (1) is a fuel cell tube (33) as a tube having a fuel cell formed on the surface.

  In order to solve the above problems, a fuel cell module according to the present invention includes a plurality of fuel cell pipes (33) and a fuel gas (31) or an oxidation gas as a fuel cell gas into the plurality of fuel cell pipes (33). A gas supply chamber (38) for supplying the agent gas (32), and a gas receiving chamber (39) for receiving the fuel cell gas (31/32) that has passed through the plurality of fuel cell pipes (1). ing. One end of each of the plurality of fuel cell pipes (33) is coupled to a first metal plate (44) as one side surface of the gas supply chamber (38), and the combined body of ceramics and metal described above is used. Forming. The other ends of the plurality of fuel cell pipes (33) are coupled to the second metal plate (45) as one side surface of the gas receiving chamber (39) to form the ceramic-metal combination described above. is doing.

  In the fuel cell module, the joint (38-2 / 39-2) between the plurality of fuel cell tube (33), the first metal plate (44) and the second metal plate (45) is the first metal. The plate (44) and the second metal plate (45) are provided at any one of a staggered lattice shape, a honeycomb shape, and a square lattice shape.

  In order to solve the above-mentioned problems, a method for bonding a ceramic and a metal according to the present invention includes: (a) a step of opening a first hole (51) having a first diameter (d0) in a metal plate (2); Forming one hole (51) into a second hole (52) having a curved surface (7) that bends smoothly in the direction of the center line (L) of the first hole (51); and (c) the second hole (52 ) And (d) inserting the ceramic tube (1) into the ring (4) and fixing the ceramic tube (1) to the ring (4).

  The method for bonding ceramics and metal according to the present invention includes (a) a step of opening a first hole (51) having a first diameter (d0) in a metal plate (2), and (b) a first hole (51). Forming a second hole (52) having a curved surface (7) that bends smoothly in the direction of the center line (L) of the first hole (51); and (c) inserting the ceramic tube (1) into the ring (4). And fixing the ceramic tube (1) to the ring (4), and (d) pressing the ring (4) into the second hole (52).

  In the above-described method of bonding ceramics and metal, the ceramic tube (1) is a fuel cell tube (1/33) as a tube having fuel cells formed on the surface.

  In the above-described method of bonding ceramics and metal, the curved surface (7) is formed substantially symmetrical with respect to the center line (L).

  In the above-described method of bonding ceramics and metal, the curved surface (7) is formed into a curved surface that is convex toward the center line (L).

  According to the present invention, it is possible to improve the sealing performance at the joint portion between the fuel battery cell tube and the metal and to enhance the sealing strength. And it becomes possible to reduce the factor of efficiency reduction of the fuel cell.

  Hereinafter, embodiments of a combined body of a ceramic tube and a metal according to the present invention will be described. FIG. 1 is a cross-sectional view showing a configuration of an embodiment of a combined body of a ceramic tube and a metal according to the present invention. The combined body includes a fuel cell tube 1 as a ceramic tube, a tube plate 2 as a metal plate, and a seal structure 3. The fuel cell tube 1 includes a plurality of fuel cells and is a ceramic tube. The tube plate 2 is a metal plate that holds the fuel battery cell tube 1. The seal structure 3 joins the fuel cell tube 1 and the tube plate 2 together.

  As shown in FIG. 1, the fuel cell tube 1 penetrates the tube plate 2 in the axial direction. The fuel cell pipe 1 shown in the figure passes a fuel cell gas (for example, a fuel gas such as hydrogen, an oxidant gas such as oxygen) through the inside. The plurality of fuel battery cell tubes 1 are gathered at a short pitch, and each penetrates the tube plate 2. The tube sheet 2 is thinly formed in a strength range where the strength is sufficient. For example, it is formed of a metal having a predetermined thickness (example: heat-resistant alloy steel, stainless steel).

  The seal structure 3 is formed of a seal layer 5, a first ring 4, and a second ring 11. The seal layer 5 is interposed between the outer peripheral surface 6 of the fuel cell pipe 1 and the inner peripheral surface of the first ring 4. The first ring 4 is interposed between the outer peripheral surface 9 of the seal layer 5 and the curved surface 7 of the tube sheet 2. The second ring 11 is a part of the tube plate 2, and the flat plate surface portion 8 and the first ring 4 that form a plane perpendicular to the center line core line (center line) L of the fuel cell tube 1 in the tube plate 2. It is interposed between and. The fuel cell tube 1, the seal layer 5, the first ring 4, and the second ring 11 are disposed concentrically with respect to the center line L and are in close contact with each other. The first ring 4 has a cylindrical shape and is made of metal (example: heat-resistant alloy steel, stainless steel). The seal layer 5 is formed of an adhesive.

  The seal layer 5 can use an inorganic adhesive, a glass adhesive, or a resin adhesive. In addition to these cases alone, it is possible to use them in an appropriate combination in consideration of the adhesive strength, sealing performance, and electrical insulation of the sealing layer 5. For example, the sealing layer 5 can be formed in a laminated manner with respect to the center line L so that the inorganic adhesive guarantees the adhesive strength, and the resin adhesive and the glass adhesive guarantee the sealing property.

In order to improve the sealing performance against gas, accurate dimensional accuracy is required. On the other hand, a ceramic tube such as the fuel cell tube 1 is not easy to perform accurate dimensional control compared to a metal tube.
By using the combination of ceramics and metal according to the present invention, even if the shape of the fuel cell tube 1 is somewhat distorted, the center line of the fuel cell tube 1 and the first ring 4 and the second ring 11 Even if the center line is slightly deviated, the seal layer 5 can absorb such distortion and misalignment. Thereby, this can improve the manufacturing yield regarding the shape, when manufacturing the fuel cell tube 1. In addition, when manufacturing the fuel cell module, it is not necessary to strictly match the center line of the fuel cell tube 1 and the center line of the first ring 4, etc., and the work can be made more efficient. The production yield can be improved.

  FIG. 2 is a cross-sectional view showing the relationship between the second ring 11 and the first ring 4 in the seal structure. The curved surface 7 of the second ring 11 is formed by drawing forming in which the tube sheet 2 is partially drawn. The elastic diaphragm structure that structures the curved surface 7 is line-symmetric with respect to the center line L, and has a bending structure that bends with an effective radius of curvature. The curved structure is smoothly curved from the direction perpendicular to the center line L to the direction of the center line L so as to protrude toward the center line L, or the curved surface 9 as the side surface of the approximate cone having the center line L as the center line. It has a curved surface 9 that bends. Of the curved surface 9, the surface closest to the center line L is formed to be a cylindrical surface in contact with the outer peripheral surface 12 of the first ring 4.

In a state where the curved surface 7 is formed, the minimum inner diameter of the curved surface 7 is formed as d. The maximum outer diameter (the outer diameter is constant) of the first ring 4 is D. The minimum inner diameter d of the curved surface 7 is slightly smaller than the maximum outer diameter D of the first ring 4:
Δd = D−d> 0
The first ring 4 is coaxially pushed into the curved surface 9 of the tube sheet 2 by pressure. When the first ring 4 is pushed into the curved surface 9 by pressure, the minimum inner diameter of the curved surface 9 increases in line symmetry to the maximum outer diameter D of the first ring 4.

  The line-symmetric curved surface 9 is surface-joined to the outer circumferential surface 12 that is coaxially line-symmetric, and the line-symmetry thereof is normally corresponding to the expansion and contraction of the tube forming plate 2 and the outer circumferential surface 12 that are heated. Maintain the close joint relationship without losing.

Next, a method for bonding ceramics and metal according to the present invention will be described with reference to FIGS.
FIG. 3 is a diagram showing an example of a processing method for the second ring 11 of the present invention.
(1) In FIG. 3A, a circular hole 52 having a diameter d0 is provided at a location where the second ring 11 of the tube plate 2 (metal plate) is to be processed. At this time, the assumed center of the second ring 11 and the center of the hole 52 are matched.

(2) The tube sheet 2 shown in FIG. Subsequently, the work member 21 is placed on the tube sheet 2. The tube sheet 2 is fixed by both working members.
At this time, the working member 20 has a working hole having a diameter of r0. The center of the work hole is aligned with the center of the hole 51. The tube hole 2 side of the working hole further expands to a diameter D0 (> r0). The diameter D0 is approximately equal to the assumed diameter of the second ring 11. The work member 21 has a hole having a diameter larger than the diameter D0. The center of the hole of the working member 20, the hole of the working member 21, and the hole 51 overlaps with the center line L.
Then, a sphere (true sphere) 22 having a diameter d larger than the diameter d 0 is pressed into the hole 51 with a predetermined pressure P. The sphere 22 is, for example, a steel ball. This state is shown in FIG.

(3) In the state of FIG. 3 (b), the sphere 22 having a diameter d is further pressed into the hole 51. Then, the ball 22 is pushed into the hole 51 so as to pass through the hole 51. Thereby, in the vicinity of the hole 51 of the tube sheet 22, a part of the vicinity of the hole 51 of the tube sheet 2 is bent toward the working hole. And the 2 ring 11 which has the curved surface 7 which curves smoothly in the centerline L direction is formed. The hole 51 is a hole 52 having a diameter slightly larger than the diameter of the hole 51 (generally the diameter of the sphere 22). This state is shown in FIG.

  When the hole 52 is provided, it is conceivable to use a cylindrical or conical pushing member instead of the sphere 22 as a member pushed into the hole 51. In that case, it is necessary to match the center line of these pushing members with the axis (center line L) passing through the center of the hole 51 and perpendicular to the tube sheet 2. And it is necessary to move these pushing members so that the center line of the pushing members overlaps the center line L. Otherwise, the second ring 11 does not have a line-symmetric shape with respect to the center line L as already described in FIG. Therefore, the contact between the first ring 4 and the second ring 11 is not sufficient, and the leak performance is lowered. That is, in order to manufacture the favorable 2nd ring 11, it is necessary to use very high-precision members and to move those members very strictly.

  On the other hand, in the present invention, since the spherical sphere 22 is used, it is not necessary to match the axes. However, it is necessary to move the sphere 22 so that the center of the sphere 22 is along the center line L. This can be easily carried out by placing the sphere 22 in the hole 51 and pushing it as it is with a force along the center line L on a plane parallel to the tube sheet 2. That is, a curved surface that is line symmetric with respect to the center line L and smoothly bends in the direction of the center line L can be formed very easily as compared with a cylindrical or conical member.

(4) In the state shown in FIG. Here, the working member 23 has a working hole having the same diameter as that of the working member 20 but does not penetrate therethrough. The first ring 4 is press-fitted into the hole 52 from the upper side in the drawing. At that time, the hole 52 slightly expands and the fourth ring is tightened. Thereby, the 1st ring 4 and the 2nd ring 11 closely_contact | adhere by line contact or surface contact. The depth of the working hole is set so that the first ring 4 stops at an appropriate position in the hole 52 when the first ring 4 is press-fitted into the hole 52. This state is shown in FIG.

FIG. 4 is a diagram illustrating an example of a method of coupling the second ring 11, the first ring 4, and the fuel cell pipe 1 according to the present invention.
(5) Insert the fuel cell tube 1 into the first ring 4 in the state of FIG. This state is shown in FIG.

(6) In the state of FIG. 4 (b), a predetermined adhesive is put between the first ring 4 and the fuel cell pipe 1 and hardened to form the seal layer 5. As a result, the first ring 4 and the fuel cell pipe 1 are fixed. This state is shown in FIG.

  As described above, ceramics and metal are bonded.

  Moreover, even if the work order of Fig.4 (a), FIG.4 (b), and FIG.4 (c) becomes reverse, it is materialized. That is, first, the fuel cell tube 1 is inserted into the first ring 4 to form the seal layer 5, and then the first ring 4 (including the fuel cell tube 1) is press-fitted into the second ring 11. At this time, the depth of the working hole of the working member 23 is made deeper than the case of FIG. 4A in consideration of the length of the fuel cell pipe 1.

  FIG. 5 is a cross-sectional view showing details of the tube sheet 2 before and after processing the second ring 11 in the seal structure. This corresponds to the states shown in FIGS.

Before the second ring 11 is formed (corresponding to before the sphere 22 is pressed in FIG. 3B), the tube plate 2 having a thickness t is fixed on the work member 20 (the work member 21 is omitted). The tube sheet 2 includes a processing portion 11a (indicated by a broken line) to be processed into the second ring 11 of the tube plate 2. The tube plate 2 has a hole having a diameter d0. The center line L passes through the center of the hole.
The working member 20 has a hole with a diameter X1. In the vicinity of the tube sheet 2, the working member 20 has a diameter up to a diameter X <b> 2 so as to form a taper. The diameter X2 is substantially equal to the diameter D0 on the tube plate 2 side of the second ring 11 to be formed.

  After the formation of the second ring 11 (corresponding to the passage after the sphere 22 having the diameter d in FIG. 3C), the processed portion 11a of the tube sheet 2 is bent by processing into a curved surface portion 11b and a cylindrical portion 11c. ing. The curved surface portion 11b forms a curved surface (7) that bends gently with a radius of curvature R from the direction of the tube sheet 2 to the direction of the center line L. The diameter on the tube plate 2 side is D0, and is connected to the tube plate 2 as it is. The diameter on the cylindrical part 11c side is d (= the diameter of the sphere 22), and is directly coupled to the cylindrical part 11c. The cylindrical portion 11c is a cylinder (annular ring) that extends coaxially from the tip of the curved surface portion 11b to the center line L. The tip is located at a depth h in the direction parallel to the center line L from the plane of the tube sheet 2 that intersects the center line L perpendicularly. The length in the direction parallel to the center line L (the height of the cylinder) is (h−R). The diameter of the cylindrical portion 11 c is d, which is the same as the diameter of the sphere 22. The center line L passes through the center of the second ring 11 (the curved surface portion 11b and the cylindrical portion 11c).

At this time, the relationship between the numerical values in FIG. 5 is expressed by the following equation from a graphical relationship.
R = (D0−d) / 2 (1)
h = (ab) + R (2)
However,
a = (D0−d0) / 2 (3)
b = π (R−t / 2) / 2 (4)

  The above relational expression does not take into account the elongation of the metal plate of the tube plate 2, and simply assumes that the processed portion 11a has a curved surface portion 11b and a cylindrical portion 11c with its length. Nevertheless, it was confirmed from the respective dimensions when the second ring 11 was actually manufactured that the above relationship was established at ± 5%. That is, in the cross section shown in the figure (a plane including the center line L), the length of the processed portion 11a and the length obtained by adding the actual processed curved surface portion 11b and the cylindrical portion 11c are substantially equal. Here, “approximately equal” means that the change in length is between −5% and + 5%.

  In the conventional interference fit structure, since the tightening force is ensured only by the in-plane direction deformation, the amount of the tightening deformation is small and the tolerance to the thermal stress deformation is small.

  In the present invention, the tube sheet 2 hardly extends in the direction along the unprocessed tube sheet 2 -curved surface portion 11b-cylindrical portion 11c in the drawing even after bending. Therefore, it can be seen that the curved surface portion 11b and the cylindrical portion 11c sufficiently maintain the elasticity of the metal plate in that direction. That is, the elastic force can flexibly cope with the stress (load) in that direction.

  FIG. 6 is a cross-sectional view showing details of the tube sheet 2 before and after inserting the first ring 4 into the second ring 11 in the seal structure. This corresponds to the states of FIG. 3 (c) to FIG. 4 (a).

  Before insertion of the first ring 4 (corresponding to FIG. 3C), the tube plate 2 and the second ring 11 are at the position (A) in the figure, and the depth is h as shown in FIG. At this time, as described above, the difference between the length of the processed portion 11a and the actual length of the curved surface portion 11b and the cylindrical portion 11c after processing is between −5% and + 5%.

  After insertion of the first ring 4 (corresponding to FIG. 4A), the tube plate 2 and the second ring 11 are in the position of the dotted line in FIG. 5B, the depth is h + α, and the diameter is d + 2β (= 2Δd). : FIG. 2). The first ring 4 is elastically held by the elongation α in the depth direction and the elongation 2β in the diameter direction. And sealing performance and support strength can be given. Even in this case, the difference between the length of the processed portion 11a and the actual length of the curved surface portion 11b and the cylindrical portion 11c after processing is between -5% and + 5%.

  FIG. 7 is a view showing the tube sheet 2 in the case where such a second ring 11 is provided. However, the first ring 4 and the fuel cell pipe 1 are omitted. As described above, the curved surface portion 11b and the cylindrical portion 11c of the second ring 11 do not have a large amount of elongation, so that the elastic force is sufficiently maintained. Thereby, even when a stress P0 (load) in a direction parallel to the surface of the tube plate 2 is applied to the tube plate 2, the stress P flows in the vicinity of the curved surface portion 11b as shown by the arrow P, and Since it can respond with an elastic force, the force does not reach to the cylindrical part 11c. Therefore, the influence on the contact portion between the first ring 4 and the second ring 11 can be reduced. From this, the combined body of ceramics and metal according to the present invention can cope with the force by the elastic force of the metal in the tube sheet 2 and the second ring 11 even when stress (load) is applied. Thereby, the seal structure can be strengthened. And durability of a seal structure can be improved and it becomes possible to extend the lifetime.

  FIG. 8 shows a comparative test apparatus for metal surface contact, and FIG. 9 shows a demonstration test apparatus for elastic metal contact according to the present invention. No adhesive is used for both contacts. In the test apparatus for comparison, only metal metal is interposed between the tube plate and the fuel cell tube (ceramics). In the demonstration test apparatus, a second ring, which is a part of the tube plate 2, is interposed between the tube plate and the fuel cell tube (ceramics) so as to have a shape like the curved surface 7 in FIG. ing.

  Both test apparatuses are provided with hydrogen gas inlets and outlets in their upper spaces (E1, F1), respectively, and nitrogen gas inlets and outlets are provided in their lower spaces (E2, F2), respectively. It has been. FIG. 10 is a graph showing the processing applied to both test apparatuses. As shown in FIG. 10, one or two H / C treatments (repetition of a high temperature of 600 ° C. and a room temperature) are performed on the seal structure portions of both test apparatuses. Leakage measurements (indicated by triangles) are performed during low temperature periods.

  FIG. 11 shows the results of the comparison target test of FIG. The horizontal axis indicates the differential pressure between the upper space and the lower space. The vertical axis represents the amount of hydrogen gas leak. Before the H / C process, the leak amount is close to zero, but after one H / C process, the leak amount increases rapidly.

  In the test apparatus for comparison, twisting around the center line occurs due to the difference in expansion coefficient between the metal tube and the fuel cell tube based on the temperature rise due to the H / C treatment, and the sealing property of the metal metal contact is lost. It is strongly presumed that

  FIG. 12 shows the results of the verification test of the present invention shown in FIG. The horizontal axis indicates the differential pressure between the upper space and the lower space. The vertical axis represents the amount of hydrogen gas leak. The scale of the vertical axis is different from FIG. Before the H / C treatment, the leak amount of the present invention is drastically reduced from the leak amount after the H / C treatment of the comparative test. The leak amount after the first H / C process is reduced to a quarter or less, and the leak amount after the second H / C process is further reduced. FIG. 12 shows that the sealing performance of the ceramic / metal combination of the present invention is remarkably excellent at high temperatures.

Next, an embodiment of a fuel cell module according to the present invention will be described with reference to the accompanying drawings.
FIG. 13 is a diagram (sectional view) showing a configuration of an embodiment of a fuel cell module according to the present invention. The fuel cell module 30 includes a plurality of fuel cell tube 33, an oxidant gas supply chamber 37, a supply chamber 38, a discharge chamber 39, a heat insulator A40-1, and a heat insulator B40-2 having a first hole 40-3. . The supply chamber 38 includes a side plate 42, a side plate 43, a tube plate A 44, a fuel gas supply port 38-1, and (a plurality of) first fitting portions 38-2. The discharge chamber 39 includes a side plate 47, a side plate 46, a tube plate B45, a fuel gas discharge port 39-1, and a plurality of second fitting portions 39-2. The oxidant gas supply chamber 7 includes a side plate 49, a tube plate A44, a tube plate B45, an oxidant gas supply port 37-1, an oxidant gas discharge port 37-2, and an oxidant gas distribution unit 37-3. Note that the configuration in FIG. 13 is omitted for the configuration related to current collection.

Each configuration will be described in detail below.
The fuel cell tube 33 is a cylindrical base tube made of porous ceramics including a plurality of fuel cells that generate power on its outer surface. One end portion of the fuel cell tube 33 is opened and fitted to the tube plate A44 of the supply chamber 38. Similarly, the other end is opened and fitted to the tube plate B45 of the discharge chamber 39. The material is exemplified by stabilized zirconia.

  The supply chamber 38 supplies the fuel gas 31 into each of the plurality of fuel battery cell tubes 33. It is made of metal such as stainless steel or heat-resistant alloy. A fuel gas supply port 38-1 for receiving the supply of the fuel gas 31 is provided. The tube plate A 44 separates the supply chamber 38 and the oxidant gas supply chamber 37. A first fitting portion 38-2 is fitted (joined) to one end of each of the plurality of fuel battery cell tubes 33.

  The discharge chamber 39 stores the used fuel gas 31 from each of the plurality of fuel battery cell tubes 33 and discharges it to the outside. It is made of metal such as stainless steel or heat-resistant alloy. A fuel gas discharge port 39-1 for discharging the spent fuel gas 31 is provided. The tube sheet B45 separates the discharge chamber 39 and the oxidant gas supply chamber 37. The other end of each of the plurality of fuel battery cell tubes 33 is fitted (joined) by the second fitting portion 39-2.

The oxidant gas supply chamber 37 supplies the oxidant gas 32 to the fuel cell tube 33. Between the supply chamber 38 (the tube plate A44) and the discharge chamber 39 (the tube plate B45), it is isolated from them and includes the fuel cell tube 33. It is made of metal such as stainless steel or heat-resistant alloy. Inside the vicinity of the tube plate A44 and the tube plate B45, a plate-like heat insulator 40 (heat insulator A40-1 and heat insulator B40-2) is fixed substantially parallel to them.
Then, an oxidant gas supply port 37-1 for receiving supply of the oxidant gas 32, an oxidant gas distribution unit that distributes the oxidant gas 32 to the fuel cell pipes 33 through which the supplied oxidant gas 32 flows. 37-3 (region sandwiched between the tube sheet B45 and the heat insulator B40-2) and an oxidizing gas discharge port 37-2 for discharging the used oxidizing gas 32.

  Tube plate A44, which is the first tube plate as one side surface of supply chamber 38 (fuel supply chamber), has holes (as many as the number of fuel cell tube 33) for connecting fuel cell tube 33 open. . The fuel cell tube 33 is opened and joined to the tube plate A44 so that one end of the fuel cell tube 33 can enter and exit the gas. The joint portion is a bonded body of the ceramic and metal of the present invention.

  The tube plate B45, which is the second tube plate as one side surface of the discharge chamber 39 (fuel discharge chamber), has holes (as many as the number of the fuel cell tube 33) for connecting the fuel cell tube 33. . The other end of the fuel battery cell tube 33 is opened and joined to the tube plate B45 so that gas can enter and exit. The joint portion is a bonded body of the ceramic and metal of the present invention.

  Since the 1st fitting part 38-2 and the 2nd fitting part 39-2 of the fuel cell tube 33 are the combination bodies of the ceramic and metal of this invention, the description is abbreviate | omitted.

The heat insulator 40 is fixed in the oxidant gas supply chamber 37 in the vicinity of the tube plate A 44 and the tube plate B 45 and outside the supply chamber 38 and the discharge chamber 39. The tube plate A44 side is the heat insulator A40-1, and the tube plate B45 side is the heat insulator B40-2.
The heat insulator B40-2 forms a flow path for the supplied oxidant gas 32 in a region (oxidant gas distribution part 37-3) sandwiched between the tube plate B15 and the heat insulator B40-2, and the flow Is limiting.
On the other hand, in the heat insulator A40-1, the tube sheet A44 and the heat insulator A40-1 substantially overlap each other.
Further, the heat insulator 40 blocks heat from the fuel cell side of the fuel cell tube 33, and the tube plate A44 and the tube plate B45, or the first fitting portion and the second fitting portion are thermally moved. Protect. Examples of the material include a heat insulating material mainly composed of porous silica, porous alumina, silica, alumina, magnesia and the like.

The heat insulator 10 will be further described.
FIG. 14 is a perspective view showing a configuration of the heat insulator B40-2. The heat insulator B40-2 has holes 40-3 for the fuel cell pipes 33 opened in a staggered pattern. The diameter of the hole 40-3 is slightly larger than the diameter of the fuel battery cell tube 33. This is because the oxidant gas 32 passes through the gap between the fuel cell tube 33 and the hole of the heat insulator 40.

  Referring to FIG. 13, heat insulator A <b> 40-1 restricts the movement of oxidant gas 32 so that oxidant gas 32 does not reach tube sheet A <b> 44. The heat insulator A40-1 has holes 40-3 'for the fuel cell pipes 33 that are opened in a staggered pattern like the heat insulator B40-2. However, the diameter of the hole 40-3 'is equal to or slightly smaller than the diameter of the fuel cell tube 33. This is to close the gap between the fuel cell tube 33 and the hole 40-3 'so that the oxidant gas 32 does not pass through.

Here, the tube sheets A44 and B45 will be further described.
FIG. 15 is a front view of the tube sheet A44B45 (FIG. 13 corresponds to the CC ′ cross section of FIG. 15). As shown in FIG. 15, the tube plates A44 and B45 have holes 53 for the ceramic-metal combination of the present invention opened in a staggered pattern.
However, the arrangement and the number of the ceramic / metal combination (fuel cell pipe 33) in the fuel cell module of the present invention are not limited to those shown in FIG. Examples of other arrangements include a honeycomb shape and a square lattice shape.

  Since the fuel cell module of the present invention uses the ceramic / metal combination of the present invention, it is possible to improve the sealing performance at the joint between the fuel cell tube and the metal and to strengthen the seal structure. I can do it. As a result, it is possible to reduce the factor of lowering the efficiency of the fuel cell that occurs at the joint between the fuel cell tube and the metal. And it becomes possible to improve the durability and lifetime of the seal structure in the fuel cell module.

FIG. 1 is a cross-sectional view showing a configuration of an embodiment of a combined body of a ceramic tube and a metal according to the present invention. FIG. 2 is a cross-sectional view showing the relationship between the second ring and the first ring in the seal structure. 3 (a) to 3 (c) are diagrams showing an example of the curved surface hole expanding method of the second ring of the present invention. 4 (a) to 4 (c) are diagrams illustrating an example of a method of coupling the second ring, the first ring, and the fuel cell tube according to the present invention. FIG. 5 is a cross-sectional view showing details of the tube sheet before and after processing the second ring in the seal structure. FIG. 6 is a cross-sectional view showing details of the tube sheet before and after inserting the first ring into the second ring in the seal structure. FIG. 7 is a view showing a tube sheet provided with such a second ring. FIG. 8 is a diagram showing a comparison test apparatus for metal surface contact. FIG. 9 is a diagram showing an elastic metal contact demonstration test apparatus according to the present invention. FIG. 10 is a graph showing the processing applied to both test apparatuses. FIG. 11 is a graph showing the comparison target test results. FIG. 12 is a graph showing the results of the verification test according to the present invention. FIG. 13 is a diagram (sectional view) showing the configuration of the embodiment of the fuel cell module of the present invention. FIG. 14 is a perspective view showing the configuration of the heat insulator. FIG. 15 is a front view of a tube sheet in the embodiment of the fuel cell module of the present invention. FIG. 16 is a cross-sectional view showing an embodiment of a ceramic / metal combination to be improved.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell tube 2 Tube plate 3 Seal structure 4 1st ring 5 Seal layer 7, 9, Curved surface 8 Flat surface part 11 2nd ring 11a Processed part 11b Curved part 11c Cylindrical part 12 Outer part 20, 22, 23 Working member 21 Sphere 31 Fuel Gas 32 Oxidant Gas 33 Fuel Cell Cell Pipe 37 Oxidant Gas Supply Chamber 37-1 Oxidant Gas Supply Port 37-2 Oxidant Gas Discharge Port 37-3 Oxidant Gas Distributor 37-4 Oxidant Gas Collection unit 38 Supply chamber 38-1 Fuel gas supply port 38-2 First fitting portion 39 Discharge chamber 39-1 Fuel gas discharge port 39-2 Second fitting portion 40 Heat insulator 40-1 Heat insulator A
40-2 Thermal insulation B
40-3 1st hole 40-3 '2nd hole 42 Side plate 43 Side plate 44 Tube plate A
45 Tube sheet B
46 Side plate 47 Side plate 51, 52, 53 Hole

Claims (13)

Ceramic tubes,
A metal plate,
A seal structure for coupling the ceramic tube and the metal plate;
The seal structure is
A sealing layer interposed between the ceramic tube and the metal plate;
A first ring interposed between the seal layer and the metal plate;
A second ring that is a part of the metal plate and is interposed between the first ring and the metal plate;
The sealing layer is adhesive to the ceramic tube and the first ring;
The second ring has a curved surface that bends smoothly in the direction of the center line of the ceramic tube;
The curved surface is in pressure surface contact or line contact with the first ring;
The curved surface is formed by bending the metal plate. A combined body of ceramic and metal. In the combination of ceramics and metal according to claim 1,
The curved surface is formed substantially symmetrical with respect to the center line. A combined body of ceramic and metal. In the combination of ceramics and metal according to any one of claims 1 to 2,
The curved surface is a curved surface convex toward the center line. A combined body of ceramic and metal. In the combination of ceramics and metal according to any one of claims 1 to 3,
The first ring is a metal cylinder, which is a combination of ceramics and metal. In the combination of ceramics and metal according to any one of claims 1 to 4,
The ceramic tube is a combination of ceramic and metal through which fuel gas or oxidant gas for a fuel cell is passed. In the combination of ceramics and metal according to any one of claims 1 to 5,
The ceramic tube is a fuel cell tube as a tube having a fuel cell formed on its surface. A combination of ceramic and metal. A plurality of fuel cell tubes;
A gas supply chamber for supplying fuel gas or oxidant gas as fuel cell gas into the plurality of fuel cell pipes;
A gas receiving chamber for receiving the fuel cell gas that has passed through the plurality of fuel cell tubes;
One end portion of each of the plurality of fuel battery cell tubes is bonded to a first metal plate as one side surface of the gas supply chamber, and forms a combined body of the ceramic and metal according to claim 6,
7. The fuel cell module according to claim 6, wherein the other end portions of the plurality of fuel battery cell tubes are coupled to a second metal plate as one side surface of the gas receiving chamber to form a composite body of the ceramic and metal according to claim 6. The fuel cell module according to claim 7, wherein
The connecting portion between the plurality of fuel battery cell tubes and the first metal plate and the second metal plate may be any one of a staggered lattice shape, a honeycomb shape, and a square lattice shape in the first metal plate and the second metal plate. A fuel cell module installed in a place. (A) opening a first hole having a first diameter in the metal plate;
(B) forming the first hole into a second hole having a curved surface that bends smoothly in the direction of the center line of the first hole;
(C) press-fitting a ring into the second hole;
(D) inserting a ceramic tube into the ring and fixing the ceramic tube to the ring. (A) opening a first hole having a first diameter in the metal plate;
(B) forming the first hole into a second hole having a curved surface that bends smoothly in the direction of the center line of the first hole;
(C) inserting a ceramic tube into the ring and securing the ceramic tube to the ring;
(D) A step of press-fitting the ring into the second hole. In the bonding method of ceramics and metal according to claim 9 or 10,
The ceramic tube is a fuel cell tube as a tube having a fuel cell formed on a surface thereof. In the bonding method of ceramics and metal according to any one of claims 9 to 11,
The curved surface is formed in substantially line symmetry with respect to the center line. The method for bonding ceramics and metal according to any one of claims 9 to 12,
The curved surface is formed into a curved surface convex toward the center line. A method of bonding ceramics and metal.

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