JP2001247372A - Hollow rodlike body composed of ceramic, metal or carbon and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a ceramic, metal or carbon hollow rodlike body 3 having improved productivity and high precision. SOLUTION: A material B 2 is built in a material A 1 composed of a ceramic, a metal or carbon to form a combined billet. The combined billet is extruded under pressure to form a combined thin rodlike body 5. Further, the material B 2 of the combined thin rodlike body 5 is removed by combustion, evaporation, sublimation, dissolution, etc., to form the hollow rodlike body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow rod made of ceramic, metal or carbon having hollow holes of any shape and number, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a general method of obtaining a hollow rod-shaped body made of ceramic, metal or carbon having a hollow body of an arbitrary shape and number, there are a press method, a casting method, an injection molding method, a rubber press method and A method of forming a hollow rod-shaped body made of ceramic, metal, or carbon by a hot press method or the like, or a method of forming a sintered body and then mechanically perforating the same has been used.

[0003]

However, these methods require very complicated steps and are technically very difficult, so that the productivity is low, and the tendency is more remarkable as the diameter becomes smaller. Was.

[0004] In order to solve this problem, a hollow extruded material is prepared by a special die using a screw extruder.
A method of obtaining a hollow rod by firing is also known.

Certainly, the use of this method is advantageous in that the production of hollow rods is simple and productive, and that the shape and number of hollow holes can be arbitrarily set by means of a die.

However, in the above-described production method, it is difficult to obtain a hollow rod-like body having a small diameter having a hollow hole in the production of a die, and since a low-viscosity material is used in the production,
After extrusion, the hollow holes were easily broken and it was difficult to obtain stable quality. Particularly, in the case of manufacturing a honeycomb-shaped hollow rod-shaped body having a small diameter, the difficulty has been compounded.

An object of the present invention is to provide a hollow rod made of ceramic, metal or carbon which solves the above-mentioned problems, and a method for producing the same.

[0008]

According to the present invention, a composite billet is formed by continuously enclosing a B material in an arbitrary shape and number in an A material made of ceramic, metal or carbon. Is extruded under pressure to form a composite fine rod, and the B material of the composite fine rod is removed by burning, evaporating, subliming, melting, etc. to form hollow holes of any shape and number. .

Further, the present invention employs the following manufacturing method for a hollow rod made of ceramic, metal or carbon.

That is, in a material A made of ceramic, metal or carbon, a material B has an arbitrary shape,
A number of composite billets continuously contained are filled in a cylinder of an extruder, and are extruded under pressure with a plunger to form a composite fine wire rod, which is fired during or after firing during the firing process The material B is removed by using any removal method such as evaporation, sublimation, and dissolution to produce a hollow rod made of ceramic, metal, or carbon.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a hollow rod according to the present invention. First, a solid billet made of ceramic, metal or carbon is prepared and used as an A material. The A material 1 is mechanically perforated to form the hollow hole 1A shown in FIG.

Next, a B material 2 made of a wax or a resin different from the material of the A material is included in the hollow hole 1A of the A material 1 to produce the composite billet shown in FIGS.

The composite billet thus obtained is extruded under pressure to form a composite fine wire rod.

Further, ceramic, metal or carbon is sintered by firing the composite fine rod at a high temperature.

Further, as a method for removing the B material, at the time of firing or after firing, the material is removed by a method such as combustion, evaporation, sublimation, or melting to form the hollow rod-shaped body 3 shown in FIG.

Next, an embodiment of the method of manufacturing the hollow rod-shaped body shown in FIG. 1 will be described.

First, a raw material of ceramic, metal or carbon is kneaded using a kneader such as a kneader or a three-roll mill, and the kneaded material is filled in a mold of a compression molding machine and pressurized to produce a solid billet. Create A hole is formed in the solid billet mechanically to form a hollow hole 1A, and the material A shown in FIG. 2 is prepared.

Next, a B material 2 different from the material of the A material 1 is included in the hollow hole 1A of the A material 1 to produce the composite billet shown in FIGS. As a method of enclosing the B material 2, the B material 2 conforming to the shape of the hollow hole 1A may be filled in the hollow hole 1A of the A material 1, or the B material 2 such as wax or resin may be heated or heated. The material softened and fluidized by the plasticizer may be poured into the hollow hole 1A. The thus obtained composite billet is filled into a cylinder of an extruder, and is extruded under pressure by a plunger to flow as shown in FIG. A composite fine rod-like body 5 having a shape similar to that of the cross section of FIG.

By firing the composite fine wire rod 5 at a high temperature, ceramic, metal or carbon is sintered.

As a method for removing the B material, at the time of firing or after firing, the material is removed by a method such as combustion, evaporation, sublimation, or dissolution.

In other words, at the time of firing, a method of removing combustion by oxidation or evaporation or sublimation by firing,
After firing, the B material 2 is removed using a removal method such as dissolution with an alkaline aqueous solution or an acid aqueous solution, and the ceramic,
A metal or carbon hollow rod 3 is prepared.

Incidentally, the hollow hole 1A of the material A in the above embodiment is not limited to a circle, but can be triangular, square, pentagonal, hexagonal or the like.
The number of holes of A can be arbitrarily set to one or more than two, and the shape thereof can be various shapes such as a lattice shape and a concentric circle shape.

Next, an embodiment of a method for manufacturing a honeycomb-shaped hollow rod-shaped body will be described.

First, the A material 1 is inserted into the hollow 1A of the A material 1 made of ceramic, metal or carbon.
A temporary composite thin wire rod-like body 15 containing a B material 2 different from the material of the above is prepared. The method of producing the temporary composite fine wire rod 15 is the same as that of the composite fine wire rod 5 shown in FIGS.

Next, in a multiplexing step, the temporary composite fine wire rod 15 is cut into an appropriate length, then a plurality of bundles are bundled and pressed to form a temporary composite billet having a multiple shape as shown in FIG. I do. At this time, although not shown, an outer skin is provided on the outer periphery as necessary. By providing the outer skin, a hollow molded body of ceramic, metal or carbon having high strength can be obtained. The temporary composite billet obtained in this way is filled into a cylinder of an extruder, and extruded into a rod shape from a die by axially extruding with a plunger under pressure, and a multiple shape similar to the cross section of the temporary composite billet is formed. To make a temporary composite fine wire rod. After repeating this multiplexing step one or more times, a final multiplexed composite billet is produced. The composite billet thus obtained is filled in a cylinder of an extruder to prepare a final composite fine wire rod having a similar shape to the cross section of the composite billet. By firing the composite fine rod at a high temperature, ceramic, metal or carbon is sintered. The method of removing the B material is performed in the same manner as in the above-described embodiment, and a honeycomb-shaped hollow rod-shaped body of ceramic, metal, or carbon is formed.

Further, another embodiment of the method for manufacturing a honeycomb-shaped hollow rod will be described.

First, a material A made of ceramic, metal or carbon is extruded in the axial direction by hollow extrusion to produce a fine rod-shaped body having a hollow hole. After cutting this hollow fine rod into an arbitrary length, the hollow hole is filled with a B material to prepare a composite fine rod.

Hereinafter, the multiplexing step is performed in the same manner as in the above-described embodiment, and a honeycomb-shaped hollow rod-shaped body of ceramic, metal or carbon is prepared.

As the ceramic material used for the material A of the present invention, ordinary ceramics, ceramics such as refractories, oxides, carbides, nitrides, etc. are used. For example, alumina, stabilized zirconia, partially stabilized zirconia, clay, Silica, kaolin, montmorillonite, pyroferrite, talc,
Ceramic materials such as mullite, zircon, spinel, boron nitride, magnesium aluminate, and zirconium silicate can be used alone or in combination. At this time, by combining a clay-based ceramic having a bonding force with another ceramic, it is possible to obtain a composite fine wire rod and a multi-composite fine wire rod having good extrusion. Further, a resin can be added to the ceramic material as needed. By adding a resin, workability during extrusion is improved.

Examples of the metal material used for the material A of the present invention include ordinary metals, alloys, and super-hard metals, which are used alone or in combination. At this time, a resin is added as needed. By adding a resin, workability during extrusion is improved.

Examples of the carbon material used in the material A of the present invention include carbon materials such as graphite and carbon black, and organic compounds which become carbon when fired at a high temperature. These may be used alone or in combination. Can be. Examples of the organic compound include a natural polymer, a synthetic polymer, a thermosetting initial condensate, pitch, asphalt, a synthetic resin, and a dry distillate of a hydrocarbon compound.

In preparing the material A of the present invention, kneading,
A liquid such as water, an organic solvent, or a plasticizer can be optionally added as an extrusion aid.

As the material B used in the present invention, any material can be used as long as it can be removed from the material A during or after firing by a method such as combustion, evaporation, sublimation, or dissolution. For example, inorganic fine powders such as metals and metal oxides, depolymerized high-molecular substances, sublimable organic compounds, resins and waxes, waxes, graphite and the like can be mentioned, and these can be used alone or in combination. The above B
The materials may be combined to form a billet or a fine rod-shaped body in accordance with the shape of the hollow hole of the hollow billet made of the material A and used as the material B.

The combination of the material A and the material B must be such that the material A is finally sintered and the material B is removed. That is, when the material A is ceramic, the ceramic is baked in an oxidizing atmosphere,
Since it sinters in any of the non-oxidizing atmospheres, all the materials exemplified as the B material can be used.
If the material is metal or carbon, the metal will be oxidized in an oxidizing atmosphere and the carbon will burn,
It is necessary to select a material that sublimates and evaporates in a non-oxidizing atmosphere and a material that is removed by melting after firing as the B material.

The outer shape of the composite billet in the manufacturing method of the present invention is preferably substantially the same as the inner shape of the cylinder of the extruder. Because if the outer dimensions of the composite billet were too small than the dimensions of the internal shape of the cylinder, the composite billet collapsed in the cylinder when pressed with a plunger, and resembled the cross-section of the composite billet It is difficult to obtain a composite fine rod.

In the composite billet, the hardness of the material A and the hardness of the material B filled in the hollow hole are preferably substantially the same.

As an extrusion method, a method in which a die 14 is provided on the cylinder 6 as shown in FIG. A method of extruding the plunger 17 in the opposite direction through a die 24 attached to the tip of
Any of so-called "reverse extrusion" may be used. Also, the shape of the extruded composite fine wire rod can be any shape by adjusting the hole of the die, the composite billet, the cylinder, and the plunger to the desired shapes.

Further, in the step of removing the B material from the composite fine wire rod which is the final extruded product, the atmosphere during the firing is a reduction, inert gas, non-oxidizing atmosphere such as vacuum, or an oxidizing atmosphere alone or in combination. At this time, it is necessary to appropriately select the atmosphere at the time of firing depending on the materials of the material A and the material B.

The maximum firing temperature is ceramic of material A,
The temperature at which the metal or carbon is sintered is preferable,
The temperature is preferably about 600 ° C. or higher. Further, after removing the B material, firing may be performed at a higher temperature. Further, the carbon hollow body can be made into a honeycomb-shaped graphite hollow rod-like body by graphitizing carbon by firing at 2000 ° C. or more.

The hollow holes of the ceramic, metal or carbon honeycomb hollow rods obtained by the production method of the present invention are filled with different materials such as metal, resin, wax, ceramic or carbon material alone or in combination. Then, if necessary, the composite material can be obtained by firing.

[0041]

EXAMPLE 1 A mixture of 60 parts of alumina, 50 parts of talc, 2 parts of polyvinyl alcohol, 100 parts of water and the above mixture was kneaded with a kneader and three rolls, and the obtained kneaded product was molded into a mold of a compression molding machine. After filling the inside into a solid billet without holes, 21 hollow holes 11A were mechanically opened concentrically as shown in FIG.

Also, 60 parts of graphite were dispersed in 40 parts of gum arabic dissolved in 100 parts of water, kneaded with three rolls, and extruded to obtain a B material.

Next, the material B was filled into the hollow hole 11A of the material A to form a composite billet. The composite billet is filled into a cylinder of an extruder and extruded to form a composite fine rod having a round cross-section,
After firing at 0 ° C. for 1 hour to sinter alumina and talc of the material A, firing at 900 ° C. for 30 minutes in O ₂ to remove graphite and gum arabic of the material B by a combustion method, FIG. A fine wire-shaped ceramic hollow rod having pores (pore diameter of about 50 μ) similar in shape to the above was obtained. Example 2 A mixture of 50 parts of graphite, 50 parts of lignin, 100 parts of water and the above mixture was kneaded by a kneader and a three-roll mill, and the obtained kneaded material was filled in a mold of a compression molding machine, and no holes were formed. After producing a solid billet, twelve square hollow holes 21A were mechanically opened in a grid pattern as shown in FIG.

In addition, 60 parts of zinc powder was dispersed in 20 parts of polyethylene dissolved in methyl ethyl ketone to prepare a kneaded material to obtain a B material.

Next, the material B was filled into the hollow hole 21A of the material A to form a composite billet. This composite billet is filled into a cylinder of an extruder and extruded to form a composite thin wire rod having a square cross section, and then is filled with N ₂ in N _2.
By baking at 00 ° C. for 1 hour to carbonize the lignin of the A material 21 and at the same time remove the polyethylene and zinc of the B material by a sublimation and evaporation method, a hole having a shape similar to the shape shown in FIG. ) Was obtained. Example 3 A mixture consisting of 70 parts of petroleum coke, 35 parts of coal tar pitch, and 100 parts of methyl ethyl ketone was kneaded with a kneader.
The kneaded material obtained by kneading with the three rolls was filled in a mold of a compression molding machine, and was pressurized. At the same time, five hexagonal hollow holes 31A were opened as shown in FIG.

In addition, a B material was obtained by melting paraffin wax.

Next, the material B was filled in the hollow hole 31A of the material A to form a composite billet. The composite billet is filled into a cylinder of an extruder and extruded to form a composite thin rod having a round cross section.
Baking at 0 ° C. for 1 hour to carbonize the coal tar pitch of the A material 31 and at the same time remove the paraffin wax of the B material by an evaporation method, thereby forming a thin wire-like carbon hollow rod having a hole similar to the shape of FIG. I got a body. Example 4 A mixture consisting of 60 parts of alumina, 50 parts of talc, 2 parts of polyvinyl alcohol, and 100 parts of water was kneaded with a kneader and a three-roll mill, and the obtained kneaded material was filled in a mold of a compression molding machine. After making a solid billet with no holes, one hollow hole was mechanically made to form a hollow hole.
Material.

Also, 60 parts of graphite were dispersed in 40 parts of gum arabic dissolved in 100 parts of water, kneaded with three rolls, and extruded to obtain a B material.

Next, the material B was filled in the hollow hole of the material A to prepare a temporary composite billet. This temporary composite billet was filled in a cylinder of an extruder and extruded to prepare a temporary composite fine wire rod having a hexagonal cross section. Next, as a multiplexing step, the temporary composite fine wire rod is cut into appropriate lengths,
Nine pieces are bundled and pressed with a hexagonal cross section to form a multi-layered temporary composite billet. This temporary composite billet was filled into a cylinder of an extruder and extruded to prepare a temporary composite fine wire rod having a hexagonal cross section.

This multiplexing step is repeated three times, and finally (4
In the multiplexing step of the third round), a hexagonal cross-section cylinder made of material A is prepared, and the temporary composite billet of the multiplex shape obtained in the third multiplexing step is inserted and filled into this cylinder, and the multiplexing with the outer skin is performed. A composite billet having a shape was filled in a cylinder of an extruder, and extruded to prepare a multi-layered composite fine wire rod with an outer skin. Next, after baking in Ar at 1200 ° C. for 1 hour to sinter the alumina and talc of the A material,
It is baked at 900 ° C. for 30 minutes in O ₂ to remove graphite and gum arabic of the B material by burning, and has a number of 130321 round holes (pore diameter of about 2 μ) obtained by repeating the multiplexing process four times. A fine-lined ceramic honeycomb hollow rod was obtained. Example 5 A mixture composed of 50 parts of graphite, 50 parts of lignin and 200 parts of water was kneaded with a kneader and a three-roll mill, and the obtained kneaded material was filled in a hollow extruder, and was shaped like a hollow hollow fine rod having a hollow hole. A body was created and used as A material.

Also, 60 parts of zinc powder was dispersed and kneaded in 20 parts of polyethylene dissolved in methyl ethyl ketone, and the kneaded product was extruded to form a round thin rod-shaped body. did.

Next, the material B was filled into the hollow hole of the material A to form a temporary composite fine wire rod. Next, as a multiplexing step, this temporary composite fine wire rod is cut into appropriate lengths and bundled into 19 pieces, and the gap is filled with a powdery A material, and pressed in a round cross section to form a temporary multi-layered rod. It is a composite billet. This temporary composite billet was filled into a cylinder of an extruder, and extruded to prepare a temporary composite thin wire rod having a multi-layered cross section.

This multiplexing step was repeated twice,
The multi-layer composite thin wire rod _Two1200 ° C in
After firing for 1 hour to carbonize the lignin of material A
Sublimation and evaporation method of polyethylene and zinc of B material at the same time
And with round holes from two multiplexing steps,
Round carbohydrate with 361 holes (hole diameter about 30μ)
A honeycomb-shaped hollow rod was obtained. Example 6 400 parts of tungsten carbide, 20 parts of acrylic,
100 parts of tyl ethyl ketone, 3 parts of dioctyl phthalate
Is kneaded with a kneader and three rolls to obtain
The kneaded material is filled into the mold of the compression molding machine,
After creating a solid billet, four
A hollow hole was made by drilling a square hole, which was used as the A material.

The B material was obtained by melting paraffin wax.

Next, the material B was filled in the hollow hole of the material A to prepare a temporary composite billet. This temporary composite billet was filled in a cylinder of an extruder, and extruded to prepare a temporary composite fine wire rod having a hexagonal cross section. Next, as a multiplexing step, the composite thin wire rod is cut into an appropriate length, bundled into 19 pieces, and pressed to form a temporary composite billet having a multiple shape.
The temporary composite billet is placed in a predetermined mold, and the surroundings thereof are filled with a powdery A material, and then pressurized to form a composite billet having a skin and a multi-layered shape. This was filled into a cylinder of an extruder, and extruded to form a multi-layered composite fine wire rod having an outer skin. This composite fine wire rod is formed by Ar
Sintering at 1100 ° C. for 1 hour to sinter tungsten carbide of material A, and at the same time remove paraffin wax of material B by an evaporation method. A honeycomb-shaped hollow rod-shaped body consisting of 76 thin-line tungsten carbides was obtained.

[0056]

As described above, according to the present invention, the productivity is improved as compared with the conventional one, and a hollow rod of ceramic, metal or carbon can be obtained with high precision. A hollow ceramic or metal or carbon hollow rod having an arbitrary shape and a number of hollow holes, which has not been obtained (particularly an outer diameter of 2 m).
m or less) have excellent characteristics such as easy production.

Further, the hollow rod-shaped body of the present invention is cut into arbitrary lengths, and is applicable to all hollow rod-shaped products such as agricultural and marine products, building materials, civil engineering, chemical industry, electronic parts, daily necessities and the like. For example, structural materials, liquid transport pipes, heat exchangers, catalyst carriers, filters, reaction tubes, felt-tip chips, pencil leads, etc., make a great contribution to the industry. Things.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a hollow rod-shaped body of the present invention.

FIG. 2 is a perspective view showing a material A of the present invention.

FIG. 3 is a sectional view showing a composite billet of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a cross-sectional view showing a flow state of a composite billet according to the present invention.

FIG. 6 is a sectional view showing a multiple composite billet according to the present invention.

FIG. 7 is a sectional view showing forward extrusion.

FIG. 8 is a sectional view showing reverse extrusion.

FIG. 9 is a cross-sectional view showing a material A of Example 1.

FIG. 10 is a cross-sectional view showing a material A of Example 2.

FIG. 11 is a cross-sectional view showing an A material of Example 3.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 A material 1A Hollow hole of A material 1 2 B material 3 Hollow rod 5 Composite thin wire rod 6 Cylinder 7 Plunger 11 A material 11A Hollow hole of A material 11 15 Temporary composite fine wire rod 17 Plunger 21 A material 21A Hollow hole of A material 21 31 A material 31A Hollow hole of A material 31

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 35/52 C04B 35/52 A 4G055 35/64 35/64 M 35/638 301 // C04B 35/56 35/56 U F term (reference) 4G001 BA24 BB24 BC17 BC23 BC26 BC34 BC35 BD36 BE31 4G030 AA36 BA34 CA07 GA14 GA19 GA21 GA27 GA28 GA33 HA08 4G032 AA02 AA04 AA09 AA12 GA06 GA08 GA11 4G053 AA00 BF01 CA07 FE02 EB01 EA01 EB01 EB17 4G054 AA00 AA05 AA09 AB09 AC00 BD08 4G055 AA00 AA08 AB03 AC10 BA14 BA41 BA43 BA62 BA73

Claims (4)

[Claims] 1. A composite billet is formed by continuously enclosing a material B of an arbitrary shape and number in a material A made of ceramic, metal or carbon, and extruding the composite billet under pressure to form a composite billet. A fine wire rod is formed, and the B material of the composite fine wire rod is removed by burning, evaporating, sublimating, melting, etc., and a hollow hole having an arbitrary shape and number is formed from ceramic or metal or carbon. Hollow rod-shaped body. 2. A composite billet, in which a material B consisting of ceramic, metal or carbon and a material B is continuously included in an arbitrary shape and number, is filled in a cylinder of an extruder and pressurized by a plunger. Forming the composite fine wire rod by extruding and removing the B material using any removal method such as combustion, evaporation, sublimation, or melting during or after firing during the manufacturing process of firing. A method for producing a hollow rod made of ceramic, metal or carbon. 3. An extruder cylinder is filled with a temporary composite billet in which material A is continuously included in the material A in an arbitrary shape and number in the axial direction, and the material is pressurized in the axial direction with a plunger. By extruding, a temporary composite fine wire rod having a cross section similar to that of the temporary composite billet is created, and then, as a multiplexing step, the temporary composite fine wire rod is cut into appropriate lengths, and then a plurality of pieces are bundled together. To form a multi-layered temporary composite billet, filling the temporary composite billet into a cylinder of an extruder, and extruding under pressure with a plunger in the axial direction to form a multi-layered temporary composite fine wire rod. 3. A hollow rod made of ceramic, metal or carbon according to claim 2, wherein after forming one or more of the multiplexing steps, a composite billet having a multiplex shape is formed in a final multiplexing step. How to make the body. 4. A material A is extruded in the axial direction by hollow extrusion to form a hollow fine wire rod, cut into an arbitrary length, and then filled with the material B in the hollow portion to temporarily prepare a composite thin wire rod. Then, as a multiplexing step, after cutting the temporary composite fine wire rod into an appropriate length, a plurality of bundles are bundled and pressed to form a multilayer composite temporary composite billet, and the temporary composite billet is extruded. By filling in a cylinder of the machine and extruding under pressure in an axial direction with a plunger, a temporary composite fine wire rod having a multiple section similar in shape to the temporary composite billet is formed. After repeating one or more times,
3. The method according to claim 2, wherein a composite billet having multiple shapes is formed in the final multiplexing step.