JPH08323213A - Production of metal honeycomb member - Google Patents

Abstract

PURPOSE: To supply an accurate and proper amt. of a solder material to a contact part by applying water repelling treatment to the surface region corresponding to the non-bonding part of one of a flat strip material and a corrugated strip material so that the ratio of the bonding parts per a unit area of both strip materials changes from the outer peripheral part of a metal honeycomb member toward the center part thereof. CONSTITUTION: When a metal honeycomb member composed of a flat strip material 1 and a corrugated strip material 2 both of which are made of a thin-walled metal plate, water repelling treatment is applied to the flat strip material 1. The water repelling treatment region 1b is formed to the central part of the flat strip material 1 in the length direction thereof so that a water repelling region increases from a winding center part to a winding terminal part. A water repelling non-treatment region 1a is formed to both end sides of the flat strip material 1 in the length direction thereof so that a water non-repelling region reduces from the winding center part to the winding terminal part. The obtained honeycomb structure is immersed in an aq. dispersion of a solder material powder to form a solder material coating layer on a solder bonding region other than a solder non-bonding region and heated to bond the solder bonding region.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a honeycomb body made of metal (hereinafter, referred to as "metal honeycomb body" for carrying an exhaust gas purifying catalyst which is used as a means for purifying exhaust gas of an automobile and used in the middle of an exhaust system. This is referred to as a metal honeycomb body).

More specifically, the present invention relates to a metal including a metal honeycomb body for carrying an exhaust gas purifying catalyst having a honeycomb structure and a metal casing (hereinafter referred to as a metal casing) for housing the metal honeycomb body. In a carrier, it relates to a method for manufacturing the metal honeycomb body.
More specifically, the present invention provides a method for manufacturing a metal honeycomb body incorporating a brazing technique that enables improvement in productivity and quality. In particular, the present invention provides a method for manufacturing a metal honeycomb body incorporating a brazing technique capable of freely changing the brazing region and the brazing ratio in the metal honeycomb body.

[0003]

2. Description of the Related Art A metal carrier for purifying exhaust gas is a catalyst for purifying exhaust gas having a honeycomb structure composed of a flat strip and a corrugated strip (for example, a catalyst system using Pt, Rh, Pd, etc.). And a metal casing (hereinafter, abbreviated as C) for accommodating and fixing the metal honeycomb body therein. It is composed. The metal carrier is referred to in the art as a metal support or a metal substrate, and may be represented by the abbreviation MS. The abbreviation MS is also used in the description of the invention.

Various structures have been proposed as the metal honeycomb body (H) which is a main constituent element of the metal carrier (MS). For example, as a typical example of this type of metal honeycomb body (H), a wound type metal honeycomb body (H) shown in FIGS. 10 to 11 is known. The winding type metal honeycomb body (H) described above is
As shown, for example, 100 μm or less (preferably 5
A flat strip (1) made of a heat-resistant thin steel plate (0 μm or less) and a corrugated strip (2) prepared by corrugating the thin steel plate so as to have mutual contact portions. Piled up on
A honeycomb body (H) having a honeycomb structure having a large number of mesh-like vent holes (cells) (3) for exhaust gas passages in the axial direction is formed by spirally forming this into a spiral shape. 10 shows a perspective view of a metal carrier (MS) composed of the wound type metal honeycomb body (H) and a metal casing (C), and FIG. 11 shows the metal carrier (M).
It is a front view of (S).

In addition, flat metal strips (1) and corrugated strips (2) are used as metal honeycomb bodies (H) in the industry.
Various structures are known due to the difference in the method of manufacturing the metal honeycomb body (H) from. For example, a layer type (see FIG. 12) in which both strips (1, 2) are laminated in layers, and further, JP-A-62-273050, JP-A-62-273051, and JP-A-1-218637.
No. 3, Special Publication No. 3-502660, JP-A-4-22785
Radial type (see FIG. 13), S-shaped type (see FIG. 14), and Tomoe type (see FIG. 1) disclosed in No. 5 and the like.
5)) and X-wrap (swastoid) type (see FIG. 16) metal honeycomb bodies.

Then, a metal carrier (M
Since the metal honeycomb body (H), which is a main constituent element of S), is used under a severe thermal environment or vibration load condition of an exhaust gas system, it can be used as a constituent member of the metal honeycomb body (H). The contact portion is firmly fixed by a fixing method such as brazing or welding so as to withstand the thermal stress. This is because the metal honeycomb body (H) is exposed to a high temperature of the exhaust gas itself and a high temperature due to an exothermic reaction between the exhaust gas and the purification catalyst, and a large deforming force due to thermal stress is generated therein. . Therefore, the abutting portions of the constituent members of the metal honeycomb body (H) are firmly fixed by a fixing method such as brazing or welding so as to withstand the thermal stress.

As a method for fixing the above-mentioned metal honeycomb body (H), for example, in consideration of effective absorption and relaxation of thermal stress, a flat strip (1) at a specific portion inside the metal honeycomb body (H) is used. ) And the corrugated plate-shaped strip (2) are fixed to each other by brazing or welding (for example, JP-B-63-44466, JP-A-2-21).
8442). Even when the contact surfaces of the metal honeycomb body (H) and the metal casing (C) are fixed to each other, it is said that specific parts of the contact surfaces of both constituent elements are fixed from the viewpoint of preventing separation of both constituent elements. A method has been proposed (for example, see Japanese Utility Model Laid-Open No. 62-19443).

As a method of applying the brazing material, a binder adhesion preventive agent is applied to a desired portion (non-adhering portion) of the constituent member of the metal honeycomb body (H), and then a binder is applied to a non-adhesion portion of the binder adhesion preventing agent. A method of applying and then applying a brazing material to the binder adhering portion by a spraying method or the like is proposed (for example,
See JP-A-4-305251 and JP-A-4-94868). However, the above-described brazing filler metal supplying method supplies the brazing filler metal to a desired optimum portion in an accurate and proper amount, and the metal honeycomb body (H) has a stable and constant fixing strength.
From the perspective of manufacturing, there is still room for improvement.

[0009]

As described above, in the conventional exhaust gas purifying metal carrier (MS), the metal honeycomb body (H) which is a main constituent element of the metal carrier (MS) is A desired portion of the contact portion of the constituent members (a flat plate-shaped band member and a corrugated plate-shaped band member) is firmly fixed by a fixing means such as brazing or welding. As the fixing means, from the viewpoint of productivity and reliability of fixing,
Generally, a brazing method is adopted. However,
In the production of the metal honeycomb body (H) by the conventional technique, a fixing method considering durability as described above has been proposed, but it is still insufficient from the viewpoint of long-term durability.

In the manufacture of the metal honeycomb body (H), brazing is widely used as the fixing means as described above, and the brazing material applied to the brazing method is that of the metal honeycomb body (H). Since it is used in a high temperature atmosphere, an expensive brazing material for high temperature such as Ni-based or Ni-Cr-based is used. For this reason, there is a strong demand for reduction of the amount used from the viewpoint of economy without impairing durability.

Further, the reduction of the amount of the Ni-based high temperature brazing material used is achieved by a diffusion alloying reaction between the brazing material component and the heat resistant band material (a flat band material and a corrugated band material). There is a strong demand for reduction of the amount of brazing filler metal used because it causes deterioration of the brazing filler metal.

[0012] Furthermore, along with the reduction of the amount of the brazing material used, there is also a strong demand for establishment of a system for accurately supplying an appropriate amount of the brazing material to a desired portion. The above point is that by accurately controlling the brazing rate and the brazing material supply rate at the abutting part of both strips (flat strip and corrugated strip) inside the metal honeycomb body, the heat stress resistance can be improved. This is an extremely important point in producing a metal honeycomb body having excellent thermal shock resistance.

The present invention was devised to solve the above-mentioned problems of the prior art. The present inventors diligently studied to solve the above-mentioned problems of the conventional technology. As a result, in the structural members (flat plate-shaped band member and corrugated plate-shaped band member) of the metal honeycomb body (H), the present inventors first apply the water repellent treatment to the portions corresponding to the non-bonding regions of the constituent members. Then, when a metal honeycomb body (H) is manufactured by using the band material and then the metal honeycomb body (H) is immersed in an aqueous dispersion of brazing filler metal powder, the above-mentioned problems of the prior art are solved. I got the knowledge that. The method for producing a metal honeycomb body (H) of the present invention has been completed based on the above findings, and since the brazing filler metal can be accurately and efficiently applied to a desired site according to the present invention, the bonding strength is improved. Is constant, which is why it has excellent long-term durability,
Further, there is provided a metal honeycomb body (H) for carrying an exhaust gas purifying catalyst which is excellent in economic efficiency.

In particular, according to the present invention, in order to improve the thermal stress (thermal shock resistance) of the metal honeycomb body (H) by brazing, the constituent members of the metal honeycomb body (H) are provided inside the metal honeycomb body (H). There is provided a method for manufacturing a metal honeycomb body capable of accurately controlling the brazing rate and the brazing material supply amount at the contact portion between the flat plate-shaped band material and the corrugated plate-shaped band material.

[0015]

The present invention will be summarized as follows.
According to the present invention, a flat band member and a corrugated plate member made of thin metal plates are stacked so as to alternately contact each other, and a desired part of a contact part where the both band parts contact is brazed to each other. In a method for manufacturing a metal honeycomb body for supporting an exhaust gas purifying catalyst having a honeycomb structure, the metal honeycomb body comprises:
(1). Bonded by brazing to the contact area per unit area of both strip materials (flat strip material and corrugated strip material) when viewed from the outer periphery to the center of the formed metal honeycomb body. Water repellent treatment of the surface portion corresponding to the non-joint portion other than the joint portion of at least one of the strips so that the ratio of the joint portions (joint ratio) changes (2). A step of forming a honeycomb structure using the strip material, (3) immersing the honeycomb structure in an aqueous dispersion of brazing material powder, and forming a brazing material coating layer on the bonding portion other than the non-bonding portion. Process,
(4). The present invention relates to a method for manufacturing a metal honeycomb body, which is manufactured by a step of heating the honeycomb structure having the brazing material coating layer formed thereon and brazing the joints. .

Hereinafter, the technical constitution and embodiments of the present invention will be described in detail with reference to the drawings. Needless to say, the present invention is not limited to the illustrated one.
Further, a wound type will be described as the metal honeycomb body (H), but the metal honeycomb body (H) of the present invention will be described.
Needless to say, is not limited to the wound type.

1 to 4 are views for explaining a method for manufacturing the metal honeycomb body (H) according to the first embodiment of the present invention.
FIG. 1 is a diagram showing a distribution of brazing joints in the front part of a metal honeycomb body (H) manufactured by a manufacturing method according to a first embodiment of the present invention described later. 1 is a front view of a conventional wound type metal honeycomb body (H).
Drawing corresponding to 1 (however, metal casing C is excluded)
Is. However, unlike FIG. 11, FIG. 1 does not include the honeycomb structure formed by winding the flat strip (1) and the corrugated strip (2), and the strip (1, 2)
The brazed portion at the contact portion of is represented by a black dot.

From FIG. 1, in the abutting portions of the strips (1, 2), the ratio of the joined portions joined by brazing, that is, the brazing to the abutting portions of both strips (1, 2) per unit area. It can be seen that the ratio of the bonded parts (hereinafter, referred to as the bonded ratio) is different in each part of the metal honeycomb body. Figure 2
Shows the change in the bonding rate (R) seen from the center of the metal honeycomb body (H) in the radius (γ) direction, and the above-mentioned characteristic points are well shown. 1 to 2, the metal honeycomb body (H) manufactured by the manufacturing method according to the first embodiment of the present invention has a bonding rate (R) when viewed from the outer peripheral portion to the central portion of the metal honeycomb body (H). ) Is an increasing type.

In the metal honeycomb body (H) having the above-mentioned bonding rate (R), the bonding rate of the outer peripheral portion of the metal honeycomb body is lower than that of the central portion, so that the outer peripheral portion has a large degree of freedom of deformation (softer than the central portion. Because of the structure, a large deformation force based on the thermal stress generated inside the metal honeycomb body (H) can be effectively absorbed and relaxed by the flexible structure of the outer peripheral portion.

Further, since the central portion is fixed more firmly than other portions, the film-out phenomenon (also called scoping or telescoping) which is observed in this kind of metal honeycomb body is effectively suppressed or prevented. It
The film-out phenomenon means that the velocity of the exhaust gas flow is the maximum in the central portion of this type of metal honeycomb body, so that the other part is formed by the contact reaction (exothermic reaction) with the carried exhaust gas purification catalyst. It is a phenomenon in which the central portion is ejected in the exhaust gas flow direction because it is heated to a higher temperature than that and a large thermal stress is generated. This film-out phenomenon
In the case of an automobile, the durability of the central portion of the metal honeycomb body is greatly impaired because it is repeatedly induced every time the engine is started and stopped.

Next, a method for manufacturing the metal honeycomb body (H) according to the first embodiment of the present invention will be described in detail with reference to FIGS. 3 to 4 are views for explaining the method for manufacturing the metal honeycomb body (H) according to the first embodiment of the present invention. FIG. 3 illustrates a water repellent treatment step relating to the first step of the present invention which is applied to the flat strip (1) and the corrugated strip (2) which are the constituent members of the metal honeycomb body (H). It is a figure. In FIG. 4, a honeycomb structure (indicated by the same H symbol as a metal honeycomb body) is manufactured from the constituent members that have been subjected to the water repellent treatment in the first step (second step), and then the honeycomb structure is formed. It is a figure explaining the process (3rd process) of applying a brazing material to a desired brazing joining site, and forming a brazing material coating layer. In the figure, (4) shows an aqueous dispersion bath of brazing filler metal powder. FIG. 5 is a diagram for explaining a conventional brazing powder distribution method. That is, FIG. 5 is a conventional brazing material powder dispersion method, which is compared with the brazing material application method (see FIG. 4) adopted in the method for manufacturing the metal honeycomb body (H) of the first embodiment of the present invention. It is a figure explaining a system. In the figure, (5) shows a brazing powder spreader, and (1c) shows a brazing powder dispersion part.

As shown in the figure, the metal honeycomb body (H) of the first embodiment of the present invention is manufactured by the following steps. (1). First, among the constituent members of the metal honeycomb body (H),
The flat strip (1) is subjected to a water repellent treatment. That is, in the case of the first embodiment, the water repellent treatment is performed only on the flat strip (1). As shown in FIG. 3 (1), in the flat strip (1), the water-repellent treated area is indicated by (1b) and the non-water-repellent treated area is indicated by (1a).

More specifically, the water repellent treated area (1
The b) and the water repellent treated area (1a) are defined on the surface of the flat strip (1) as follows. (i) The water-repellent treatment region (1b) is formed in the central portion and the length direction of the flat strip (1). Furthermore, flat strip (1)
The water-repellent regions are formed in the lengthwise regions on both sides of the coil from the winding center (the center of the formed metal honeycomb body) to the winding end (the outer periphery of the formed metal honeycomb). It is formed to increase. (ii) On the other hand, in the non-water-repellent treated area (1a), the non-water-repellent area is reduced from the center of the winding toward the end of the winding on both ends and in the length direction of the flat strip (1). Is formed.

In FIG. 3 (1), comparing the three divided areas (11, 12, 13) of the flat strip (1) at the longitudinal portions of both ends of the flat strip (1), The contents of formation (definition) of the water-repellent treated area (1b) and the non-water-repellent treated area (1a) can be understood. Needless to say,
In the present invention, the non-water repellent treated region (1a) is a region where the brazing material coating layer is formed in the third to fourth steps and is brazed and joined.

In the present invention, the water-repellent treated region (1b), in other words, the non-water-repellent treated region (1), is formed on the surface of the flat strip (1), for example, the surfaces of the portions in the lengthwise direction on both sides thereof.
In order to change the image component cloth of a), the desired method may be used. For example, the image component may be transferred onto the surface of the flat strip (1) by using a roll having the same transferred image as that of the defined section and impregnated with a water repellent. At that time, one large-diameter roll may be used, but FIG.
It goes without saying that three rolls of small diameter may be used to share each of the three sections (11, 12, 13) of the flat strip (1).

In the present invention, the water repellent treatment in the first step is a treatment for making the surface of a desired part of the flat strip (1) water repellent. In the step of the water-repellent treatment of the present invention, the means for exhibiting the water-repellent function can be adopted without any restriction. As a water-repellent treatment means applied to the surface of a desired portion of the above-mentioned flat strip (1), for example, a coating means of a substance having a water-repellent ability such as wax or paraffin emulsion, metal soap, mineral oil or asphalt is adopted. it can. Further, the water repellent coating may be formed by a method of forming a metal coating layer, for example, plating or ion plating. Furthermore, the water repellent function may be exhibited by making the surface roughness of the flat strip (1) different.

(2). In the method for manufacturing a metal honeycomb body (H) according to the first embodiment of the present invention, the second step is to perform the water-repellent treatment of the flat plate-shaped strip (1) and the corrugated plate-shaped strip ( 2) is a step of forming a wound type honeycomb structure by a conventional method.

(3). In the method for producing a metal honeycomb body (H) according to the first embodiment of the present invention, the third step is to use the honeycomb structure formed in the second step as an aqueous dispersion of brazing filler metal powder. Is a step of forming a brazing material coating layer on a portion other than the water repellent treated area (1b), that is, a non-water repellent treated area (1a). FIG. 4 shows a step of dipping the brazing filler metal powder of the honeycomb structure (H) in the aqueous dispersion bath (4). In the present invention, as the brazing filler metal powder,
Ni-based brazing filler metal for high temperature (Ni-
Cr-Si system, Ni-Si-B system, etc.) may be used. In addition, in order to prepare an aqueous dispersion from the Ni-based brazing material, the Ni-based brazing material is mixed with a surfactant (dispersant) or the like at a desired concentration (for example, solid content concentration of 40% to 80%).
%).

By the immersion treatment of the brazing filler metal powder of the honeycomb structure (H) in the aqueous dispersion bath (4) in the third step, the brazing filler metal is uniformly and accurately supplied only to the non-water repellent treated region (1a). To be done. It goes without saying that the brazing material is not supplied to the water repellent treated area (1b) due to the water repellent function of the water repellent treated area (1b). In the first embodiment of the present invention, at the beginning of the dipping treatment, a brazing material coating layer is formed on the entire surface of the non-water-repellent treated region (1a) of the flat strip (1), but with the passage of time. In addition, the coating layer of the brazing material on the flat strip (1) migrates to the contact portion of the flat strip (1) and the corrugated strip (2) and the vicinity thereof by the capillary phenomenon. Therefore, a strong fixing strength can be obtained at the time of brazing in the next step. The above-mentioned point, that is, the migration of the brazing material to the abutting portion also occurs in the corrugated plate material (2) in the abutting relationship which is not subjected to the water-repellent treatment, and contributes to firm fixation. .

The non-water repellent area (1) of the flat strip (1)
In a), the part that does not come into contact with the corrugated strip (2) is
As described above, the coating layer of the brazing filler metal on the surface migrates to the contact portion side, so that the brazing filler metal component and the metal component of the flat strip (1) diffuse at the above-mentioned portion during brazing in the next step. The alloying reaction is suppressed. The above-mentioned points also occur in the corrugated strip material (2) in the same manner, whereby deterioration of the heat resistance of (1, 2) is prevented.

(4). In the method for manufacturing a metal honeycomb body (H) according to the first embodiment of the present invention, the fourth step is a brazing joint portion other than the non-brazing joint portion manufactured by the third step, in other words This is a brazing step of the honeycomb structure in which the brazing material coating layer is formed in the non-water repellent treated area (1a). Although the brazing process is related to the brazing material used, for example, in the case of high-temperature Ni-based brazing material, a vacuum furnace is used to obtain a vacuum degree of 1
X10 ^-3 Torr or less, in an inert or reducing atmosphere,
It may be performed under the condition of 1100 to 1300 ° C.

The above-mentioned metal honeycomb body (H) of the present invention
5, particularly by the brazing material supply method of the present invention, compared to the conventional brazing material powder fixing binder application and brazing material supply method shown in FIG. Since a predetermined amount of brazing material can be supplied, a high quality metal honeycomb body (H) can be manufactured.

In the present invention, the flat plate-shaped strip material (1) constituting the metal honeycomb body (H) is a strip material which is used when a normal metal monolith type metal honeycomb body is manufactured, for example, chromium. Steel (chrome 13%
~ 25%), Fe-Cr 20% -Al 5%, or other heat-resistant stainless steel, or heat-resistant stainless steel to which a rare earth metal (REM such as Ce or Y) is added to improve high-temperature oxidation resistance. Thickness of 40μm-100, such as steel
A band material of about μm is used. As the corrugated strip (2), the corrugated plate (1) corrugated so as to have a predetermined substantially sine wave or trapezoidal wave is used. The flat strip (1) and the corrugated strip (2) may have different plate thicknesses or different materials. In particular, the flat strip (1) and the corrugated strip (2) containing Al or the surface of which an Al layer is provided are heat-treated to give a whisker-shaped or mushroom-shaped surface. Alumina (Al
It is preferable to deposit ₂ O ₃ ). The whisker-like alumina layer is preferable because it can firmly hold the washcoat layer for carrying the exhaust gas purifying catalyst such as Pt, Pd, and Rh.

The metal honeycomb body (H) manufactured according to the first embodiment of the present invention is the same as the conventional wound type metal honeycomb body shown in FIGS. 10 to 11 in the metal casing (C). The metal carrier (MS) for purifying the exhaust gas is housed and fixed in the. As a material used for manufacturing the metal casing (C) that constitutes the metal carrier (MS), the same kind of heat resistant steel as the strip material that constitutes the metal honeycomb body (H) may be used. Alternatively, a double structure having excellent heat and corrosion resistance, specifically, a double structure metal casing (C) using ferritic stainless steel in the inner part and austenitic stainless steel in the outer part may be used. Good. Needless to say, the brazing step of the metal honeycomb body (H) of the present invention is performed by the metal carrier (M
S) It can be carried out at the time of brazing the metal honeycomb body (H) and the metal casing (C) at the time of manufacturing.

The metal carrier (MS) may be loaded with a catalyst for purifying exhaust gas by a conventional method.
That is, a wash coat layer as a support layer of the exhaust gas purifying catalyst is formed on the wall surface of the honeycomb structure of the metal honeycomb body (H), and more specifically, the catalyst activity can be increased. Γ-A with surface area
forming a coating layer of l ₂ O ₃ and then Pt, P
An exhaust gas purifying catalyst such as a d, Rh type redox catalyst may be supported.

FIG. 6 is a diagram for explaining the method for manufacturing the metal honeycomb body (H) according to the second embodiment of the present invention, and is a diagram corresponding to FIG. 1 of the first embodiment. The second embodiment is greatly different from the first embodiment in the water repellent treatment step of the first step, and other technical configurations are substantially the same. In the second embodiment, the water repellent treatment is applied to both the flat strip (1) and the corrugated strip (2). That is, the water repellent treatment of the flat strip (1) is performed in the same manner as in the first embodiment. On the other hand, corrugated strip (2)
The water repellent treatment is also carried out in exactly the same manner as the flat strip (1). In the case of the second embodiment, as compared with the first embodiment, the water-repellent treated region is formed also in the corrugated strip material (2), so that the applied amount of the brazing material is accurately controlled. Therefore, a higher quality metal honeycomb body (H) can be manufactured.

FIG. 7 is a diagram for explaining a method for manufacturing a metal honeycomb body according to the third embodiment of the present invention. FIG. 3 (1) of the first embodiment (a mode of water repellent treatment of a flat strip). Is a diagram corresponding to FIG. In a third embodiment,
On the surface of the plate-shaped strip (1), a total of three strips composed of a non-water-repellent treated region (1a) and a water-repellent treated region (1b) on both sides in the longitudinal direction and on the central region, and In the meantime, a total of two strips consisting of the water repellent treated area (1b) are defined. The strip having the water-repellent treated area (1b) and the non-water-repellent treated area (1a) has the same contents as the strips on both sides of FIG. 3 (first embodiment). That is, in the case of the third embodiment, the non-water repellent treated area (1a)
Since the correct amount of brazing material is applied in the next step in the three strips consisting of the water-repellent treated area (1b), the metal honeycomb body is securely and firmly brazed at both ends and the center. A honeycomb body (H) can be manufactured. Further, since the central portion has a rigid structure and the outer peripheral portion has a flexible structure, a metal honeycomb body (H) having excellent thermal stress resistance (thermal shock resistance) can be manufactured.

FIG. 8 is a view for explaining the metal honeycomb body of the fourth embodiment of the present invention, which can be regarded as a modification of the third embodiment (FIG. 7). That is, FIG. 8 is a diagram corresponding to FIG. 7. In the fourth embodiment (FIG. 8), the water-repellent treatment is performed in the first step so that the bonding rate decreases over the entire width of the formed metal honeycomb body (H) in the direction from the central part to the outer peripheral part. To be done.

FIG. 9 is a view for explaining the metal honeycomb body of the fifth embodiment of the present invention, which can be regarded as a modification of the first embodiment (FIG. 1). That is, FIG. 9 is a diagram corresponding to FIG. In the present invention, the meaning that the bonding rate changes in the direction from the outer peripheral portion to the central portion of the metal honeycomb body should be construed in the broadest sense, for example, to increase. In FIG. 9, two circles (circle) indicated by broken lines, Y1 (circle at the center) and Y
When the radius (or diameter) of 2 (circle of outer periphery) is small (Y1 = Y2), the bonding rate (R) is the same,
The present invention does not intend such a thing. Figure 9
Should be understood that the bonding rate (R) increases from the outer peripheral part of the metal honeycomb body (H) toward the central part.

Various modifications are possible in the metal honeycomb body (H) manufactured according to the present invention. Although not shown, the front (cross-section) structure of the metal honeycomb body (H) is
The structure is not limited to the circular structure of the first embodiment, and may have a racetrack shape, an elliptical shape, a polygonal shape, or another modified cross-section. In addition, the bonding rate (R) does not increase continuously from the outer peripheral portion to the central portion of the metal honeycomb body (H) as in the first embodiment, but increases gradually. It may be.

[0041]

The metal carrier for purifying exhaust gas of the present invention (M
The method for manufacturing the metal honeycomb body (H), which is a main component of S), is accurate and appropriate especially for the desired contact portion between the flat plate-shaped strip and the corrugated plate-shaped strip that are the constituent members of the metal honeycomb body. It incorporates a method of supplying a certain amount of brazing filler metal and a method of freely changing the proportion (joining rate) of brazing at the contact portion.

In the production of the metal honeycomb body, accurate and proper supply of the brazing filler metal is important from the viewpoint of firmly adhering the abutting portions of the constituent members, that is, ensuring durability for a long period of time. In addition, an accurate and appropriate amount of brazing filler metal is supplied by an alloying reaction of a brazing filler metal component and a strip material (a flat strip material and a corrugated strip material). Is also important from the viewpoint of economical efficiency because the brazing material is an expensive brazing material for high temperature. Furthermore,
Durability of metal honeycomb body (made from heat stress and heat shock)
In order to improve the above, it is an important development subject to make the metal honeycomb body have a desired flexible structure by the brazing technique so as to absorb and relax the thermal stress.

The brazing method adopted in the method for manufacturing a metal honeycomb body of the present invention satisfies the above-mentioned various viewpoints (needs), and the present invention provides excellent durability over a long period of time and is economical. An excellent metal honeycomb body is manufactured.

[Brief description of drawings]

FIG. 1 is a diagram showing a distribution of brazing joints in a front part of a metal honeycomb body (H) manufactured by a method for manufacturing a metal honeycomb body according to a first embodiment of the present invention.

FIG. 2 is a graph showing the distribution of brazing joint portions in the front portion of the metal honeycomb body (H) shown in FIG.

FIG. 3 is a diagram illustrating a water repellent treatment step in the method for manufacturing the metal honeycomb body (H) according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a step of forming a brazing material coating layer in the method for manufacturing the metal honeycomb body (H) according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining a conventional brazing powder distribution and supply system.

FIG. 6 is a diagram illustrating a water repellent treatment step in the method for manufacturing the metal honeycomb body (H) according to the second embodiment of the present invention.

FIG. 7 is a diagram illustrating a water repellent treatment step in the method for manufacturing the metal honeycomb body (H) according to the third embodiment of the present invention.

FIG. 8 is a diagram illustrating a water repellent treatment step in the method for manufacturing the metal honeycomb body (H) according to the fourth embodiment of the present invention.

[Fig. 9] Fig. 9 is a view showing a brazing joint portion of a facing portion of the metal honeycomb body (H) manufactured by the method for manufacturing the metal honeycomb body (H) of the fifth embodiment of the present invention.

FIG. 10 is a perspective view of a metal carrier (MS) having a wound type metal honeycomb body (H) as a main constituent element.

11 is a front view of the metal carrier (MS) shown in FIG.

FIG. 12 is a front view of a metal carrier (MS) including a hierarchical type metal honeycomb body (H) as a main component.

FIG. 13 is a front view of a metal carrier (MS) including a radial type metal honeycomb body (H) as a main component.

FIG. 14 is a front view of a metal carrier (MS) including an S-shaped metal honeycomb body (H) as a main constituent element.

FIG. 15 is a front view of a metal carrier (MS) having a toe-shaped metal honeycomb body (H) as a main constituent element.

FIG. 16 is a metal carrier (MS) mainly composed of an X-wrap (swath-shaped) type metal honeycomb body (H).
FIG.

[Explanation of symbols]

 MS: Metal carrier H: Metal honeycomb body C: Metal casing 1: Flat strip material 2: Corrugated strip material 3: Cell (mesh-shaped vent passage) 1a ... …… Non-water-repellent treated area 1b of flat strip ………… Water-repellent treated area 2a of flat strip ………… Non-water-repellent treated area 2b of corrugated strip ………… Water repellent area

Claims (11)

[Claims] 1. A flat metal strip made of a thin metal plate and a corrugated metal strip are stacked so as to alternately come into contact with each other, and a desired portion of an abutting portion where the both strips come into contact is brazed to each other. In the method for manufacturing a metal honeycomb body for carrying an exhaust gas purifying catalyst having a honeycomb structure, the metal honeycomb body is (1). At least one of the strips is changed so that the ratio (joint ratio) of the joined portions joined by brazing to the abutting portions per unit area of the strips (flat strip and corrugated strip) changes. Water-repellent treatment of the surface portion corresponding to the non-joint portion other than the joint portion, (2); a step of forming a honeycomb structure using the water-repellent treated band member, (3). The honeycomb structure The body is dipped in an aqueous dispersion of brazing filler metal and the joints other than the non-joint And a step of forming a brazing material coating layer on the honeycomb structure, wherein the honeycomb structure having the brazing material coating layer formed thereon is heat-treated to braze the joint portion. Method for manufacturing metal honeycomb body. 2. The method for manufacturing a metal honeycomb body according to claim 1, wherein the bonding rate increases from the outer peripheral portion of the formed metal honeycomb body toward the central portion. 3. Only at the abutting portions of both strips at both end portions of the formed metal honeycomb body and in the vicinity thereof,
The joining rate changes. 4. The method for manufacturing a metal honeycomb body according to claim 1, wherein a bonding rate is changed at a contact portion of both strips in the entire inside of the formed metal honeycomb body. 5. The method for producing a metal honeycomb body according to claim 1, wherein the water repellent treatment step is performed by applying a water repellent agent. 6. The method for manufacturing a metal honeycomb body according to claim 1, wherein the water repellent treatment step is a method of varying the surface roughness of the strip. 7. The method for manufacturing a metal honeycomb body according to claim 1, wherein the water repellent treatment step is performed by forming a metal coating on the surface of the strip. 8. The method for manufacturing a metal honeycomb body according to claim 1, wherein the water repellent treatment is performed only on the flat strip material. 9. The method for producing a metal honeycomb body according to claim 1, wherein the water-repellent treatment is performed on both the flat plate-shaped strip material and the corrugated plate-shaped strip material. 10. The method for producing a metal honeycomb body according to claim 1, wherein the step of forming the brazing material coating layer is a method of drying after the immersion treatment of the brazing material powder in the aqueous dispersion. 11. A metal honeycomb body, which is a wound type, a laminated type, a radial type, an S-shaped type, a tongue-shaped type,
And a method of manufacturing a metal honeycomb body according to claim 1, which is selected from the group of X-wrap (swastika) type.