WO2012043749A1 - 炭化珪素質セラミックス及びハニカム構造体 - Google Patents
炭化珪素質セラミックス及びハニカム構造体 Download PDFInfo
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- WO2012043749A1 WO2012043749A1 PCT/JP2011/072432 JP2011072432W WO2012043749A1 WO 2012043749 A1 WO2012043749 A1 WO 2012043749A1 JP 2011072432 W JP2011072432 W JP 2011072432W WO 2012043749 A1 WO2012043749 A1 WO 2012043749A1
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- Prior art keywords
- silicon carbide
- type
- crystal
- mass
- honeycomb structure
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
- C04B2235/9607—Thermal properties, e.g. thermal expansion coefficient
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
- F01N3/28—Construction of catalytic reactors
- F01N3/2803—Construction of catalytic reactors characterised by structure, by material or by manufacturing of catalyst support
- F01N3/2825—Ceramics
- F01N3/2828—Ceramic multi-channel monoliths, e.g. honeycombs
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
- Y10T428/24149—Honeycomb-like
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/26—Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
- Y10T428/268—Monolayer with structurally defined element
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
Definitions
- the present invention relates to a silicon carbide ceramic and a honeycomb structure. More specifically, the present invention relates to a silicon carbide ceramic that has a small amount of change in specific resistance due to a temperature change and can generate heat when energized, and a honeycomb structure made of such a silicon carbide ceramic.
- Silicon carbide is a highly conductive compound semiconductor, and has excellent heat resistance and chemical stability. Therefore, silicon carbide is used as an energization heating element used in a high temperature electric furnace or the like. In general, silicon carbide exhibits a behavior that “the specific resistance drops sharply and starts to increase with a minimum of about 400 ° C.” as the temperature rises due to heat generated by energization. This is believed to be based on silicon carbide being a semiconductor. That is, since silicon carbide is a semiconductor, the number of conduction electrons that can be excited from the impurity level to the conduction band increases as the temperature rises. This behavior lowers the specific resistance from room temperature to about 400 ° C. After about 400 ° C., the mobility of conduction electrons decreases due to the thermal vibration of the lattice, so that it is considered that the specific resistance tends to increase slightly.
- silicon carbide exhibits negative characteristics (property that the specific resistance decreases with increasing temperature) in the temperature range from room temperature to about 400 ° C. Therefore, when silicon carbide is used as a heating element and the temperature is raised from normal temperature to about 400 ° C. by energization, there are the following problems. That is, as the temperature rises, the specific resistance of silicon carbide (heating element) decreases, and there is a risk that the current increases rapidly. In addition, it is very difficult to control the temperature of a heating element having a large rate of change of the above “specific resistance temperature change” (100 ⁇ specific resistance change / temperature change).
- a silicon carbide heating element comprising “a silicon carbide sintered body containing at least 10% ⁇ -SiC crystal particles and in which nitrogen is dissolved” has been proposed in an attempt to reduce the temperature change of the specific resistance.
- a conductive silicon carbide ceramic material mainly composed of “silicon carbide in which the ratio of 6H type in the total crystal system is 90% or less and in which nitrogen is dissolved” and having a predetermined resistance temperature coefficient has been proposed. (For example, refer to Patent Document 2).
- the silicon carbide heating element described in Patent Document 1 contains at least 10% of ⁇ -SiC (3C type) crystal particles that are metastable phases. For this reason, when energized at a high voltage, there is a risk of transition to 4H type or 6H type due to thermal history, and heat resistance may be reduced.
- the conductive silicon carbide ceramic material described in Patent Document 2 has little temperature dependency of electrical resistance, the specific resistance at room temperature is low at 1 ⁇ ⁇ cm or less. Therefore, the conductive silicon carbide based ceramic material is not preferable because an excessive current may flow when energized at a high voltage, which may damage an electric circuit or the like.
- the present invention has been made in view of such problems of the prior art.
- the present invention provides a silicon carbide-based ceramic that is small in the amount of change in specific resistance due to a temperature change and that can generate heat when energized, and a honeycomb structure made of such a silicon carbide-based ceramic.
- the following silicon carbide ceramic and honeycomb structure are provided.
- a plurality of silicon carbide particles containing the silicon carbide crystal and silicon that bonds the silicon carbide particles together, and the silicon content is 10 to 40% by mass [1] or [2 ]
- [7] A honeycomb structure made of the silicon carbide ceramic according to any one of [1] to [6].
- An energizing exothermic catalyst carrier comprising the honeycomb structure according to [7] and generating heat when energized.
- the silicon carbide based ceramic of the present invention contains 0.1 to 25% by mass of 4H type silicon carbide crystal and 50 to 99.9% by mass of 6H type silicon carbide crystal. Therefore, according to the silicon carbide based ceramic of the present invention, the amount of change in specific resistance due to temperature change is small, and heat can be generated by energization.
- the honeycomb structure of the present invention is made of the silicon carbide ceramic of the present invention. Therefore, according to the honeycomb structure of the present invention, the amount of change in the specific resistance due to temperature change is small, it is possible to generate heat by energization, and the occurrence of partition defects and the like are also suppressed.
- FIG. 1 is a perspective view schematically showing an embodiment of a honeycomb structure of the present invention. It is a mimetic diagram showing a section parallel to a cell extension direction of one embodiment of a honeycomb structure of the present invention.
- Silicon carbide ceramics One embodiment of the silicon carbide based ceramic of the present invention contains a silicon carbide crystal, and in the silicon carbide crystal, “0.1 to 25% by mass of 4H type silicon carbide crystal and 50 to 99.9% by mass”. Of 6H type silicon carbide crystal ”.
- the silicon carbide ceramic of this embodiment contains 0.1 to 25% by mass of 4H type silicon carbide crystal and 50 to 99.9% by mass of 6H type silicon carbide crystal. Therefore, the silicon carbide ceramic of this embodiment has a small amount of change in specific resistance due to a temperature change, and can stably generate heat by energization.
- the silicon carbide crystal contained preferably contains a 4H type silicon carbide crystal, a 6H type silicon carbide crystal, and a 15R type silicon carbide crystal. More preferably.
- examples of the structure of the silicon carbide crystal include “hexagonal 2H type, 4H type, 6H type”, “cubic 3C type”, “rhombohedral 15R type”, and the like. These crystal structures are usually mixed in the silicon carbide crystal (the whole), and the “specific resistance change amount due to temperature change (specific resistance temperature change)” varies depending on the type of crystal structure.
- the content of 4H-type silicon carbide crystal in the silicon carbide crystal is 0.1 to 25% by mass, preferably 0.1 to 17% by mass, and more preferably 0.1 to 5% by mass.
- the crystal components other than the 4H type silicon carbide crystal in the silicon carbide crystal are preferably 6H type silicon carbide crystal and 15R type silicon carbide crystal.
- the content of the 4H type silicon carbide crystal in the silicon carbide crystal is less than 0.1% by mass, the electric conduction through the crystal phase of the 6H type silicon carbide crystal becomes dominant, and the amount of change in specific resistance due to temperature change. Is unfavorable because of the increase.
- the content of the 4H type silicon carbide crystal in the silicon carbide crystal is larger than 25% by mass, the specific resistance becomes low, and when the current is applied, the current may flow excessively, which may damage the electric circuit or the like. It is not preferable.
- the silicon carbide crystal may contain 15 to 20% by mass of 15R type silicon carbide crystal, and more preferably 0.1 to 12% by mass.
- the band gap of the 15R type silicon carbide crystal is smaller than that of the 4H type silicon carbide crystal. For this reason, the influence on the inversion layer channel mobility by the oxide trap density in the vicinity of the interface is small. Further, the bulk mobility of the 15R type silicon carbide crystal is low in anisotropy, and has the effect of stabilizing the resistance when energized.
- the content of the 15R type silicon carbide crystal in the silicon carbide crystal is larger than 20% by mass, the conductivity by the 15R type silicon carbide crystal becomes dominant and the temperature change of the specific resistance cannot be reduced.
- the 3C type silicon carbide crystal contained in the silicon carbide crystal is preferably 5% by mass or less, and more preferably 3% by mass or less. Since 3C type silicon carbide is a metastable phase, it transitions to 4H type or 6H type due to thermal history. For this reason, when the content rate of the 3C type silicon carbide crystal in the silicon carbide crystal is larger than 5% by mass, the heat resistance may be lowered.
- the remaining components in the silicon carbide crystal Is preferably a 6H-type silicon carbide crystal.
- the “remaining component” means a component other than “4H type silicon carbide crystal, 15R type silicon carbide crystal and 3C type silicon carbide crystal”.
- the silicon carbide ceramic of the present embodiment preferably has a nitrogen content (solid solution amount) of 0.01% by mass or less. If the solid solution amount of nitrogen is larger than 0.01% by mass, it is not preferable because an electric circuit or the like may be damaged by excessive current. This is because when the solid solution amount of nitrogen is larger than 0.01% by mass, the specific resistance becomes low and an electric current may flow excessively when energized.
- the nitrogen content is a value measured by ICP (Inductively Coupled Plasma) emission spectroscopy.
- the silicon carbide ceramic of the present embodiment is preferably a porous fired body (sintered body).
- the porosity is preferably 30 to 65%, and more preferably 35 to 50%. If the porosity is less than 30%, an electric circuit or the like may be damaged by an excessive current. This is because when the porosity is less than 30%, the specific resistance is low, and an excessive current may flow when energized. Furthermore, if the porosity is less than 30%, the heat capacity increases, so that the rate of temperature rise during energization may be slow. If the porosity is larger than 65%, the specific resistance tends to be high, and it is difficult to generate heat sufficiently because current does not easily flow when energized.
- the porosity is a value measured with a mercury porosimeter.
- the average pore diameter is preferably 2 to 30 ⁇ m, more preferably 4 to 20 ⁇ m. When the average pore diameter is smaller than 2 ⁇ m, the specific resistance may become too large. When the average pore diameter is larger than 30 ⁇ m, the specific resistance may be too small.
- the average pore diameter is a value measured with a mercury porosimeter.
- the silicon carbide ceramic of this embodiment preferably has a specific resistance (R 20 ) at 20 ° C. of 2 to 100 ⁇ ⁇ cm, and more preferably 20 to 80 ⁇ ⁇ cm.
- the specific resistance at 400 ° C. is preferably 1 to 25 ⁇ ⁇ cm, and more preferably 5 to 20 ⁇ ⁇ cm.
- the silicon carbide ceramic of this embodiment can be appropriately made to generate heat by energization. If the specific resistance at 400 ° C. is larger than 25 ⁇ ⁇ cm, it may be difficult to generate heat sufficiently because current does not flow easily when energized. When the specific resistance at 400 ° C. is smaller than 1 ⁇ ⁇ cm, an electric current may flow excessively when energized, which may damage an electric circuit or the like.
- the specific resistance at 400 ° C. is the specific resistance when the silicon carbide ceramic is heated to 400 ° C. by energization heat generation.
- the silicon carbide ceramic of the present embodiment has a difference (R 20 ⁇ R Min ) between a specific resistance (R 20 ) at 20 ° C. and a minimum specific resistance (R Min ) of 80 ⁇ ⁇ cm or less. Preferably, it is 40 ⁇ ⁇ cm or less.
- R 20 ⁇ R Min a difference between the specific resistance at 20 ° C. and the minimum specific resistance
- the difference between the specific resistance at 20 ° C. and the minimum specific resistance is small, the change in specific resistance due to energization heat generation becomes small when energized. Therefore, this can prevent an excessive current from flowing.
- the difference between the specific resistances is greater than 80 ⁇ ⁇ cm, the current may flow excessively when energized, which may damage the electric circuit or the like.
- the “minimum specific resistance” is a value of the specific resistance when the specific resistance value of the silicon carbide based ceramic becomes the smallest when the temperature of the silicon carbide based ceramic is changed.
- the temperature (TR -Min ) at which the specific resistance is minimum is preferably 500 ° C. or less, and more preferably 400 ° C. or less.
- the specific resistance starts to increase at a lower temperature, it is possible to avoid an excessive flow of current, and it is possible to prevent damage to an electric circuit or the like.
- the entire silicon carbide based ceramic may be formed by bonding silicon carbide, or a plurality of silicon carbide particles are bonded by silicon (metal silicon: Si) to form silicon carbide.
- the whole ceramic material may be formed.
- the silicon carbide particles contain the above silicon carbide crystal (“silicon carbide crystal containing 0.1 to 25% by mass of 4H type silicon carbide crystal and 50 to 99.9% by mass of 6H type silicon carbide crystal)” It is preferable to contain. It is further preferable that the silicon carbide particles are formed of the silicon carbide crystal.
- the silicon carbide based ceramic of the present embodiment contains “a plurality of silicon carbide particles and silicon for bonding the silicon carbide particles”, the specific resistance can be lowered.
- the silicon content (the silicon content relative to the total of silicon carbide particles and silicon) is preferably 10 to 40% by mass, and more preferably 15 to 35% by mass.
- the silicon content is less than 10% by mass, the porosity is increased and the specific resistance is likely to be increased. As a result, it becomes difficult for the current to flow when energized, so that it is difficult to generate heat sufficiently.
- the silicon content is less than 10% by mass, the strength is lowered, and cracks may occur due to thermal cycling or temperature distribution during energization.
- the average particle diameter of the silicon carbide particles is 10 to 50 ⁇ m.
- the thickness is 15 to 35 ⁇ m.
- the average particle diameter of the silicon carbide particles contained in the silicon carbide ceramics is a value measured by image processing software after observing the cross section and surface of the silicon carbide ceramics with an SEM.
- ImageJ manufactured by NIH (National Institute of Health)
- NIH National Institute of Health
- the cross section of the silicon carbide ceramics As for the cross section of the silicon carbide ceramics, the unevenness of the cross section is filled with resin, further polished, and the polished surface is observed. On the other hand, regarding the surface of the silicon carbide based ceramic, the cut sample (partition wall) is observed as it is. The arithmetic average of the observation results of the “cross section” 5 fields and the “surface” 5 fields is taken as the average particle diameter of the silicon carbide particles contained in the silicon carbide ceramics.
- the silicon carbide ceramics of this embodiment has a temperature of 400 to 900 ° C. due to heat generation when a voltage of 100 to 800 V is applied.
- honeycomb structure of the present invention is a honeycomb structure made of one embodiment of the silicon carbide ceramic of the present invention.
- the honeycomb structure 100 of the present embodiment is a porous structure that partitions and forms “a plurality of cells 2 extending from one end face 11 to the other end face 12” that are fluid flow paths. It is a cylindrical structure having a partition wall 1 and an outer peripheral wall 3 located at the outermost periphery. Note that the honeycomb structure of the present embodiment does not necessarily have an outer peripheral wall.
- the honeycomb structure of the present embodiment is made of the silicon carbide ceramic according to the embodiment of the present invention, the amount of change in specific resistance due to temperature change is small, and heat can be generated by energization. is there. Therefore, the honeycomb structure of the present embodiment can be used as an “electric heating element” that generates heat when energized. Furthermore, when the honeycomb structure of the present embodiment is used as a catalyst carrier (a current-generating heat-generating catalyst carrier) and the catalyst is supported and used for purification of exhaust gas, temperature control during current-generated heat generation can be stably performed. This is because the specific resistance change of the honeycomb structure (energized exothermic catalyst carrier) of the present embodiment is small even when the temperature changes greatly.
- the partition wall thickness is preferably 50 to 200 ⁇ m, and more preferably 70 to 130 ⁇ m.
- the partition wall thickness is preferably 50 to 200 ⁇ m, and more preferably 70 to 130 ⁇ m.
- the honeycomb structure 100 of the present embodiment preferably has a cell density of 40 to 150 cells / cm 2 , and more preferably 70 to 100 cells / cm 2 .
- the purification performance of the catalyst can be enhanced while reducing the pressure loss when the exhaust gas is flowed.
- the cell density is lower than 40 cells / cm 2 , the catalyst supporting area may be reduced.
- the cell density is higher than 150 cells / cm 2 , when the honeycomb structure 100 is used as a catalyst carrier and a catalyst is supported, the pressure loss when the exhaust gas flows may increase.
- the partition wall 1 is preferably porous.
- the porosity of the partition wall 1 is preferably 30 to 65%, and more preferably 35 to 50%. If the porosity is less than 30%, the heat capacity increases, and the rate of temperature rise during energization may be slow. When the porosity is larger than 65%, the strength is lowered, and there is a risk that cracks may occur due to thermal cycling or temperature distribution during energization.
- the average pore diameter of the partition wall 1 is preferably 2 to 30 ⁇ m, and more preferably 4 to 20 ⁇ m.
- the average pore diameter is smaller than 2 ⁇ m, the specific resistance may become too large.
- the average pore diameter is larger than 30 ⁇ m, the specific resistance may be too small.
- the thickness of the outer peripheral wall 3 constituting the outermost periphery of the honeycomb structure 100 of the present embodiment is preferably 0.1 to 2 mm. If it is thinner than 0.1 mm, the strength of the honeycomb structure 100 may be lowered. If it is thicker than 2 mm, the area of the partition wall supporting the catalyst may be small.
- the shape of the cell 2 in a cross section perpendicular to the extending direction of the cell 2 is a quadrangle, a hexagon, an octagon, or a combination thereof.
- the shape of the honeycomb structure of the present embodiment is not particularly limited.
- the shape of the honeycomb structure of the present embodiment includes, for example, a cylindrical shape (cylindrical shape) having a circular outer peripheral shape on the bottom surface, a cylindrical shape having an oval shape on the bottom peripheral surface, and a polygonal shape (square, pentagonal, Hexagonal shape, heptagonal shape, octagonal shape, etc.).
- the honeycomb structure has a total area of 2000 to 20000 mm 2 , and more preferably 4000 to 10000 mm 2 in the entire bottom surface.
- the length of the honeycomb structure in the central axis direction is preferably 50 to 200 mm, and more preferably 75 to 150 mm.
- the isostatic strength of the honeycomb structure 100 of the present embodiment is preferably 1 MPa or more, and more preferably 3 MPa or more.
- the isostatic strength is preferably as large as possible, but when considering the material, structure, etc. of the honeycomb structure 100, the upper limit is about 10 MPa.
- Isostatic strength is a value measured by applying hydrostatic pressure in water.
- An embodiment of the energization exothermic catalyst carrier of the present invention is a catalyst carrier that includes the above-described embodiment of the honeycomb structure of the present invention and generates heat when energized.
- the “energized exothermic catalyst carrier” means a “catalyst carrier” that generates heat when energized (by passing an electric current).
- the energization heat-generating catalyst carrier of the present embodiment includes the above-described embodiment of the honeycomb structure of the present invention, the amount of change in specific resistance due to temperature change is small, and heat can be generated by energization. . Therefore, when a catalyst is supported on the energization exothermic catalyst carrier of this embodiment to form a catalyst body, and the catalyst body is used for exhaust gas purification, heat generation by energization can be performed stably. This is because the specific exothermic catalyst carrier of this embodiment has little change in specific resistance even when the temperature changes.
- the energization exothermic catalyst carrier of the present invention may consist of one embodiment of the honeycomb structure of the present invention, or may include components other than the embodiment of the honeycomb structure of the present invention. Good. Examples of components other than the embodiment of the honeycomb structure of the present invention include an electrode for applying a voltage. That is, the energization exothermic catalyst carrier of the present embodiment includes one embodiment of the honeycomb structure of the present invention and “an electrode for applying a voltage to one embodiment of the honeycomb structure of the present invention”. Is preferred.
- the method for producing the silicon carbide ceramic of the present embodiment is not particularly limited.
- Examples of the method for producing the silicon carbide ceramic of the present embodiment include a method having a forming raw material preparation step, a forming step, and a firing step.
- the forming raw material preparation step is preferably a step of preparing a forming raw material by mixing a plurality of types of silicon carbide ceramic powders “containing 4H type silicon carbide crystals at different contents”.
- the molding step is preferably a step of forming the molded body by molding the molding raw material.
- the firing step is preferably a step of firing the molded body to produce a silicon carbide ceramic in which the content of 4H-type silicon carbide crystals is adjusted to a desired value.
- the silicon carbide content in the silicon carbide ceramics used for preparing the forming raw material is preferably 60% by mass or more. Moreover, it is preferable that the content rate of the silicon (metallic silicon) in the silicon carbide ceramics used for preparation of a shaping
- “plural types” of “plural types of silicon carbide based ceramic powders” are “classified (distinguished)” when silicon carbide based ceramic powders are classified (distinguished) by “content of 4H type silicon carbide crystals contained”. It means “multiple types”. That is, it is assumed that silicon carbide ceramic powders having different contents of 4H-type silicon carbide crystals are different types of silicon carbide ceramic powders.
- a plurality of types of silicon carbide ceramic powders means a plurality of “silicon carbide ceramic powders having different contents of 4H type silicon carbide crystals”.
- silicon carbide ceramics in which the content of the 4H type silicon carbide crystal in the silicon carbide crystal is a desired value can be obtained. That is, first, two or more kinds of specific silicon carbide ceramic powders (with different contents of 4H type silicon carbide crystals) are prepared. Then, they are mixed at a predetermined ratio. Thereby, the content rate of the 4H type silicon carbide crystal in the silicon carbide crystal of the obtained silicon carbide based ceramic can be set to a desired value.
- the number of silicon carbide ceramic powders to be mixed is preferably 2 to 5, more preferably 2 types.
- the silicon carbide ceramic powder contained in the forming raw material may be one kind of silicon carbide ceramic powder.
- the silicon carbide crystal contained in the silicon carbide ceramic powder contains 0.1 to 25% by mass of 4H type silicon carbide crystal and 50 to 99.9% by mass of 6H type silicon carbide crystal. It is preferable.
- the content rate of 4H type silicon carbide crystals in the silicon carbide ceramics in the forming raw material is adjusted so that the content rate of 4H type silicon carbide crystals in the silicon carbide ceramics to be produced becomes a desired value.
- “content ratio of 4H type silicon carbide crystal” is specified, the content of 4H type silicon carbide crystal with respect to the entire silicon carbide crystal in silicon carbide ceramics (or silicon carbide ceramic powder) unless otherwise specified. Means rate.
- a silicon carbide ceramic powder having the same or lower “content ratio of 4H type silicon carbide crystal” than the “content ratio of desired 4H type silicon carbide crystal” is referred to as “low 4H type silicon carbide ceramic powder” or “ This is referred to as “low 4H type silicon carbide powder”.
- a silicon carbide ceramic powder having the same or higher “content ratio of 4H type silicon carbide crystal” than the “content ratio of desired 4H type silicon carbide crystal” is referred to as “high 4H type silicon carbide ceramic powder”.
- high 4H type silicon carbide powder it is referred to as “high 4H type silicon carbide powder”.
- the plurality of types of silicon carbide ceramic powders containing “4H type silicon carbide crystals at different contents” are “low 4H type silicon carbide ceramic powder” and “high 4H type silicon carbide ceramic powder”. It is composed of “Low 4H type silicon carbide ceramic powder” constituting a plurality of types of silicon carbide ceramic powder “containing 4H type silicon carbide crystals at different contents” may be one type or a plurality of types. There may be. Further, “high 4H type silicon carbide ceramic powder” constituting a plurality of types of silicon carbide ceramic powder “containing 4H type silicon carbide crystals at different contents” may be one type or a plurality of types. It may be of a type.
- the “content ratio of the desired 4H type silicon carbide crystal” refers to the “content ratio of the 4H type silicon carbide crystal in the silicon carbide crystal in the silicon carbide based ceramic (desired silicon carbide based ceramic) to be manufactured”.
- the “content ratio of 4H type silicon carbide crystal” in the silicon carbide based ceramic powder is the content ratio of 4H type silicon carbide crystal with respect to the entire silicon carbide crystal in the silicon carbide based ceramic powder.
- the content of the 4H type silicon carbide crystal in the silicon carbide crystal is preferably 0.01 to 15% by mass.
- the content of the 4H type silicon carbide crystal in the silicon carbide crystal in the “high 4H type silicon carbide ceramic powder” is preferably 0.5 to 40% by mass.
- the content rate of the 4H type silicon carbide crystal in the silicon carbide crystal means the content rate of the 4H type silicon carbide crystal with respect to the entire silicon carbide crystal.
- “Low 4H type—content of 4H type silicon carbide crystal in silicon carbide crystal in silicon carbide ceramic powder” is referred to as “low 4H type—content of 4H type silicon carbide crystal in silicon carbide powder”.
- the “content ratio of 4H type silicon carbide crystal in the silicon carbide crystal in the high 4H type-silicon carbide based ceramic powder” is referred to as “content ratio of 4H type silicon carbide crystal in the high 4H type—silicon carbide powder”.
- the difference between “low 4H type—content of 4H type silicon carbide crystal in silicon carbide powder” and “high 4H type—content of 4H type silicon carbide crystal in silicon carbide powder” is 30% by mass or less. Is preferable, and it is still more preferable that it is 15 mass% or less.
- the resistance is locally lowered and the temperature distribution may be non-uniform.
- the low 4H type-silicon carbide powder and the high 4H type-silicon carbide powder are plural, the following is preferable. That is, regardless of which of the plurality of types is selected, the above-mentioned “content of 4H type silicon carbide crystal in low 4H type-silicon carbide powder” and “4H type silicon carbide crystal in high 4H type—silicon carbide powder” The difference from the “content ratio” is preferably within the above range.
- the silicon carbide crystal in the low 4H type-silicon carbide based ceramic powder mainly contains 6H type silicon carbide crystal in addition to the 4H type silicon carbide crystal.
- a 6H type silicon carbide crystal is mainly contained in addition to the 4H type silicon carbide crystal
- a 6H type other than the 4H type silicon carbide crystal is excluded except for a trace amount of 1% by mass or less. This means that only type silicon carbide crystals are contained.
- the silicon carbide crystal in the high 4H type-silicon carbide ceramic powder preferably contains mainly 6H type silicon carbide crystal in addition to the 4H type silicon carbide crystal.
- the silicon carbide crystal in the low 4H type-silicon carbide ceramic powder may contain 15R type silicon carbide crystal or 3C type silicon carbide crystal in addition to 4H type silicon carbide crystal and 6H type silicon carbide crystal. Good.
- the silicon carbide crystal in the high 4H type-silicon carbide based ceramic powder contains 15R type silicon carbide crystal and 3C type silicon carbide crystal in addition to 4H type silicon carbide crystal and 6H type silicon carbide crystal. It may be.
- silicon carbide ceramics containing 15R-type silicon carbide crystals low 4H-type silicon carbide-type ceramic powder, high 4H-type-silicon carbide-type ceramic powder, or both of these, It is preferable that a silicon crystal is contained.
- the above “both” means “both low 4H type-silicon carbide ceramic powder and high 4H type-silicon carbide ceramic powder”.
- the method for producing the silicon carbide ceramic of the present embodiment will be described in more detail.
- the shape of the silicon carbide ceramic is not particularly limited, but in the following description of the manufacturing method, a method for manufacturing a silicon carbide ceramic (honeycomb structure) having a honeycomb structure will be described.
- silicon carbide ceramics (silicon-silicon carbide ceramics) containing “a plurality of silicon carbide particles and silicon (metal silicon) that bonds the silicon carbide particles to each other” It is preferable to produce silicon carbide ceramics by the method.
- a molding raw material is prepared by mixing a plurality of types of silicon carbide ceramic powders "containing 4H type silicon carbide crystals at different contents" (molding raw material preparation step). More specifically, a low 4H type silicon carbide ceramic powder and a high 4H type silicon carbide ceramic powder are expressed as “the content of 4H type silicon carbide crystals in the silicon carbide crystals of the resulting silicon carbide ceramics. So that the desired value is obtained. Furthermore, metal silicon powder is mixed with the mixture to produce a forming raw material. At this time, it is preferable to further add additives usually used in the production of silicon-silicon carbide ceramics, such as a binder, a surfactant, a pore former, and water, as necessary. In addition, the order which mixes each raw material is not specifically limited. Further, the low 4H type-silicon carbide ceramic powder and the high 4H type-silicon carbide ceramic powder are sometimes collectively referred to simply as “silicon carbide ceramic material”.
- the average particle size of the silicon carbide based ceramic powder is preferably 10 to 50 ⁇ m, and more preferably 15 to 35 ⁇ m. If the thickness is smaller than 10 ⁇ m, the specific resistance tends to be high, so that when current is applied, current does not flow easily and heat generation may be difficult. If it is larger than 50 ⁇ m, the porosity tends to be low, so that the heat capacity tends to be large, and the rate of temperature rise during energization may be slow.
- the average particle diameter of the silicon carbide based ceramic powder was measured by a laser diffraction / scattering particle size distribution measuring apparatus (for example, LA-920 manufactured by Horiba, Ltd.) based on the Fraunhofer diffraction theory or Mie scattering theory. % Particle size.
- the total content of metal silicon and silicon carbide ceramic material in the forming raw material is preferably 30 to 90% by mass.
- the ratio (mass ratio) of the metal silicon in the forming raw material to the total of the metal silicon and the silicon carbide ceramic raw material is preferably 10 to 40% by mass, and more preferably 15 to 35% by mass.
- binder examples include methyl cellulose, hydroxypropyl methyl cellulose, hydroxypropoxyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol. Among these, it is preferable to use methyl cellulose and hydroxypropoxyl cellulose in combination.
- the content of the binder is preferably 2.0 to 10.0 parts by mass when the total mass of the silicon carbide ceramic material and the metal silicon is 100 parts by mass.
- the water content is preferably 20 to 60 parts by mass when the total mass of the silicon carbide ceramic raw material and metal silicon is 100 parts by mass.
- ethylene glycol, dextrin, fatty acid soap, polyalcohol or the like can be used as the surfactant. These may be used individually by 1 type and may be used in combination of 2 or more type.
- the content of the surfactant is preferably 0.1 to 2.0 parts by mass when the total mass of the silicon carbide ceramic material and the metal silicon is 100 parts by mass.
- the pore former is not particularly limited as long as it becomes pores after firing, and examples thereof include graphite, starch, foamed resin, water absorbent resin, silica gel and the like.
- the content of the pore former is preferably 0.5 to 10.0 parts by mass when the total mass of the silicon carbide ceramic material and the metal silicon is 100 parts by mass.
- the average particle size of the pore former is preferably 10 to 30 ⁇ m. If it is smaller than 10 ⁇ m, pores may not be formed sufficiently. If it is larger than 30 ⁇ m, the die may be clogged during molding.
- the average particle diameter of the pore former is a value measured by a laser diffraction method.
- the forming raw material is kneaded to form a clay.
- molding raw material and forming a clay For example, the method of using a kneader, a vacuum clay kneader, etc. can be mentioned.
- honeycomb formed body by extruding clay (forming raw material) (forming step).
- the honeycomb molded body is a cylindrical molded body having a porous partition wall for partitioning and forming “a plurality of cells extending from one end surface to the other end surface” serving as a fluid flow path, and an outer peripheral wall located at the outermost periphery. Is the body. Note that the honeycomb formed body does not necessarily have to include an outer peripheral wall.
- a die having a desired overall shape, cell shape, partition wall thickness, cell density and the like.
- a cemented carbide which does not easily wear is preferable.
- the outer shape, size, partition wall thickness, cell density, outer peripheral wall thickness, etc. of the honeycomb molded body should be appropriately determined in accordance with the structure of the honeycomb structure to be manufactured in consideration of shrinkage during drying and firing. Can do.
- the drying method is not particularly limited, and examples thereof include an electromagnetic heating method such as microwave heating drying and high-frequency dielectric heating drying, and an external heating method such as hot air drying and superheated steam drying. Among these, it is preferable to dry a certain amount of moisture by an electromagnetic heating method and then dry the remaining moisture by an external heating method. Thereby, the whole molded object can be dried rapidly and uniformly so that a crack may not arise.
- an electromagnetic heating method such as microwave heating drying and high-frequency dielectric heating drying
- an external heating method such as hot air drying and superheated steam drying.
- the cutting method is not particularly limited, and examples thereof include a method using a circular saw cutting machine.
- Pre-baking is preferably performed at 400 to 550 ° C. for 0.5 to 20 hours in an air atmosphere.
- the method of temporary baking is not particularly limited, and can be performed using an electric furnace, a gas furnace, or the like.
- a honeycomb formed body silicon carbide ceramics having a honeycomb structure
- the content of 4H-type silicon carbide crystals is adjusted to a desired value by firing the honeycomb formed body that has been subjected to temporary firing.
- firing conditions it is preferable to heat at 1400 to 1500 ° C. for 1 to 20 hours in an inert atmosphere such as nitrogen or argon.
- an oxidation treatment at 1200 to 1350 ° C. for 1 to 10 hours in order to improve durability.
- the firing method is not particularly limited and can be performed using an electric furnace, a gas furnace, or the like.
- the manufacturing method of one embodiment of the silicon carbide ceramic of the present invention is a method of manufacturing a honeycomb structure made of one embodiment of the silicon carbide ceramic of the present invention. It is also a manufacturing method of one embodiment. Furthermore, the manufacturing method of an embodiment of the honeycomb structure of the present invention is also a method of manufacturing an energizing exothermic catalyst carrier provided with the embodiment of the honeycomb structure of the present invention.
- a low 4H type-silicon carbide ceramic powder (low 4H type-powder) and a high 4H type-silicon carbide ceramic powder (high 4H type-powder) are mixed to prepare a forming raw material (forming raw material).
- Preparation step In the preparation of the forming raw material, the above-mentioned “low 4H type-powder” and “high 4H type-powder” are used, and the “content of 4H type silicon carbide crystal in the silicon carbide crystal of the resulting silicon carbide ceramics is: Mix to achieve the desired value. And an additive is added as needed, without adding metal silicon, and a shaping
- the forming raw material is formed into a desired structure such as a honeycomb structure by extrusion molding or the like as necessary to form a formed body (forming step).
- the obtained molded body can be fired by a known method to obtain a silicon carbide ceramic in which the content of 4H-type silicon carbide crystals is adjusted to a desired value (firing step).
- Example 1 Silicon carbide powder having a 4H-type silicon carbide crystal content of 0.1% by mass, silicon carbide powder and metal silicon powder having a 4H-type silicon carbide crystal content of 26.0% by mass, 70.0: 0.0 : Mixed at a mass ratio of 30.0.
- the silicon carbide powder is a silicon carbide ceramic powder.
- hydroxypropylmethylcellulose as a binder and a water-absorbing resin as a pore former were added, and water was added to form a molding raw material.
- the obtained forming raw material was kneaded with a vacuum kneader to prepare a columnar clay.
- the silicon carbide powder and the metal silicon powder may be collectively referred to as “ceramic raw material”.
- a silicon carbide powder having a content of 4H type silicon carbide crystals of 0.1% by mass is a “low 4H type silicon carbide powder”. And the silicon carbide powder whose content rate of 4H type silicon carbide crystal
- the content of the binder was 7 parts by mass when the entire ceramic raw material was 100 parts by mass.
- the content of the pore former was 3 parts by mass when the entire ceramic raw material was 100 parts by mass.
- the water content was 42 parts by mass when the entire ceramic raw material was 100 parts by mass.
- the average particle diameter of the silicon carbide powder was 30 ⁇ m, and the average particle diameter of the metal silicon powder was 6 ⁇ m. Moreover, the average particle diameter of the pore former was 25 ⁇ m.
- the average particle diameter of the silicon carbide powder, the metal silicon powder, and the pore former is a value measured by a laser diffraction method.
- the obtained columnar kneaded material was molded using an extrusion molding machine to obtain a cylindrical honeycomb molded body.
- the obtained honeycomb formed body was dried by high-frequency dielectric heating, and then dried at 120 ° C. for 2 hours using a hot air dryer, and a predetermined amount was cut at both ends.
- honeycomb formed body was degreased, fired, and further oxidized to obtain a honeycomb structure (silicon carbide based ceramic).
- the degreasing conditions were 550 ° C. for 3 hours.
- the firing conditions were 1450 ° C. and 2 hours in an argon atmosphere.
- the conditions for the oxidation treatment were 1300 ° C. and 1 hour. Nitrogen is not dissolved in the obtained honeycomb structure.
- the average pore diameter of the partition walls of the obtained honeycomb structure was 15 ⁇ m, and the porosity was 40%.
- the average pore diameter and porosity are values measured with a mercury porosimeter.
- the honeycomb structure had a partition wall thickness of 120 ⁇ m and a cell density of 90 cells / cm 2 .
- the bottom surface of the honeycomb structure was a circle having a diameter of 90 mm, and the length of the honeycomb structure in the cell extending direction was 100 mm.
- the isostatic strength of the obtained honeycomb structure was 7 MPa. Isostatic strength is the breaking strength measured by applying hydrostatic pressure in water.
- the average particle diameter of the silicon carbide particles constituting the partition walls of the obtained honeycomb structure was 30 ⁇ m.
- the average particle diameter of the silicon carbide particles constituting the partition walls of the honeycomb structure is a value obtained by observing a cross section of the silicon carbide ceramics with an SEM and using an image processing apparatus.
- the column of “Crystal structure ratio (mass%)” indicates each crystal structure (4H type silicon carbide crystal, 6H type silicon carbide crystal, etc.) with respect to the entire silicon carbide crystal in the silicon carbide ceramic in the fired body.
- the ratio (mass%) is shown.
- the column of average particle diameter ( ⁇ m) indicates the average particle diameter ( ⁇ m) of silicon carbide particles in the silicon carbide ceramics. This is a value measured by image processing software (ImageJ) by observing the cross section / film surface of the silicon carbide ceramics with an SEM.
- the content rate (mass%) of a metal silicon shows the content rate of the metal silicon with respect to the sum total of the silicon carbide particle
- the content rate of metallic silicon is a value measured by fluorescent X-ray analysis.
- the porosity indicates the porosity of the partition walls of the honeycomb structure made of silicon carbide ceramics.
- a test piece of 4 mm ⁇ 2 mm ⁇ 40 mm is cut out from the honeycomb structure (silicon carbide based ceramic), and the resistance value is measured by a four-terminal method. The resistance value is measured at 20 ° C., and further measured from 100 ° C. to 800 ° C. every 100 ° C. The specific resistance is calculated from the obtained resistance value.
- Silicon carbide crystal polymorphs are quantified by X-ray diffraction of powder samples (Ruska's method (J. Mater. Sci., 14, 2013-2017 (1979))).
- the stability during energization is measured by measuring the temperature distribution in the carrier when energized at 600 V using a thermocouple (the temperature is measured uniformly at 39 points in the honeycomb structure), and the average temperature in the carrier is Evaluation was made by determining the temperature distribution when the temperature reached 500 ° C.
- Examples 2 to 51, Comparative Examples 1 to 3 A honeycomb structure (silicon carbide based ceramic) was produced in the same manner as in Example 1 except that part of the production conditions was changed as shown in Table 1. With respect to the obtained honeycomb structure, the “specific resistance” was measured by the above method. The results are shown in Table 2.
- Table 1 the “content (mass%)” column of “low 4H type silicon carbide powder” indicates the content of “low 4H type silicon carbide powder” with respect to the total of silicon carbide powder and metal silicon. Show. Further, the “content (mass%)” column of “high 4H type silicon carbide powder” indicates the content of “high 4H type silicon carbide powder” with respect to the total of the silicon carbide powder and the total of metal silicon.
- the column of “Crystal structure ratio (mass%)” of “Low 4H type silicon carbide powder” shows each crystal structure (4H type silicon carbide crystal, 6H type silicon carbide for the entire silicon carbide crystal in the low 4H type silicon carbide powder. The ratio (mass%) of a crystal etc. is shown.
- the column of “Crystal structure ratio (mass%)” of “High 4H type silicon carbide powder” each crystal structure (4H type silicon carbide crystal, 6H type) with respect to the entire silicon carbide crystal in the high 4H type silicon carbide powder.
- the ratio (mass%) of silicon carbide crystal or the like is shown.
- the content rate (mass%) of metallic silicon shows the content rate of metallic silicon with respect to the sum total of the silicon carbide powder and metallic silicon.
- content of a pore making material is shown by content ratio (mass part) when "the sum total of silicon carbide powder and metal silicon" is 100 mass parts.
- the silicon carbide ceramics (honeycomb structures) of Examples 1 to 51 have a difference (R 20 ⁇ R) between the specific resistance (R 20 ) at 20 ° C. and the minimum specific resistance (R Min ). It can be seen that Min ) is small and the temperature change of the specific resistance is small. On the other hand, it can be seen that the silicon carbide ceramic of Comparative Example 1 does not contain 4H-type silicon carbide crystals, so that R 20 -R Min is large and the temperature change of the specific resistance is small. Moreover, it turns out that the temperature used as minimum specific resistance is high. Further, the silicon carbide ceramic of Comparative Example 2 has a high content of 4H type silicon carbide crystals.
- the specific resistance (R 20 ) at 20 ° C. is small and the effect of generating heat by energization is low.
- the silicon carbide ceramic of Comparative Example 3 has a high content of 4H type silicon carbide crystals and a low content of 6H type silicon carbide crystals. Therefore, it can be seen that the specific resistance (R 20 ) at 20 ° C. is small and the temperature at which the minimum specific resistance is reached is high.
- the silicon carbide ceramic of the present invention can be suitably used as a heating element.
- the honeycomb structure of the present invention and the energizing exothermic catalyst carrier of the present invention can be suitably used as a catalyst carrier for an exhaust gas purification device that purifies exhaust gas from automobiles.
- 1 partition wall
- 2 cell
- 3 outer peripheral wall
- 11 one end face
- 12 the other end face
- 100 honeycomb structure
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Abstract
Description
本発明の炭化珪素質セラミックスの一の実施形態は、炭化珪素結晶を含有し、炭化珪素結晶中に、「0.1~25質量%の4H型炭化珪素結晶、及び50~99.9質量%の6H型炭化珪素結晶」が含有されるものである。
本発明のハニカム構造体の一実施形態は、上記本発明の炭化珪素質セラミックスの一実施形態を材質とするハニカム構造体である。図1、2に示すように、本実施形態のハニカム構造体100は、流体の流路となる「一方の端面11から他方の端面12まで延びる複数のセル2」を、区画形成する多孔質の隔壁1と、最外周に位置する外周壁3とを有する筒状の構造体である。尚、本実施形態のハニカム構造体は、必ずしも外周壁を備える必要はない。
本発明の通電発熱性触媒担体の一実施形態は、上記本発明のハニカム構造体の一実施形態を備え、通電により発熱する触媒担体である。「通電発熱性触媒担体」とは、通電(電流を流すこと)することにより発熱する「触媒担体」を意味する。
(4-1)本実施形態の炭化珪素質セラミックスの製造方法は、特に限定されない。本実施形態の炭化珪素質セラミックスの製造方法は、例えば、成形原料調製工程と、成形工程と、焼成工程とを有する方法を挙げることができる。成形原料調製工程は、「4H型炭化珪素結晶をそれぞれ異なる含有率で含有する」複数種類の炭化珪素質セラミックス粉末を混合して成形原料を調製する工程であることが好ましい。成形工程は、上記成形原料を成形して成形体を形成する工程であることが好ましい。焼成工程は、上記成形体を焼成して4H型炭化珪素結晶の含有率が所望の値に調整された炭化珪素質セラミックスを作製する工程であることが好ましい。この場合、成形原料の調製に使用する炭化珪素質セラミックス中の炭化珪素の含有率は、60質量%以上であることが好ましい。また、成形原料の調製に使用する炭化珪素質セラミックス中の珪素(金属珪素)の含有率は、40質量%以下であることが好ましい。ここで、「複数種類の炭化珪素質セラミックス粉末」の「複数種類」は、炭化珪素質セラミックス粉末を、「含有される4H型炭化珪素結晶の含有量」によって種類分け(区別)したときの「複数種類」を意味する。つまり、4H型炭化珪素結晶の含有量が異なる炭化珪素質セラミックス粉末を、異なる種類の炭化珪素質セラミックス粉末であるとする。そして、「複数種類の炭化珪素質セラミックス粉末」というときは、複数の「4H型炭化珪素結晶の含有量が異なる炭化珪素質セラミックス粉末」のことを意味する。
4H型炭化珪素結晶の含有率が0.1質量%の炭化珪素粉末、4H型炭化珪素結晶の含有率が26.0質量%の炭化珪素粉末及び金属珪素粉末を、70.0:0.0:30.0の質量割合で混合した。炭化珪素粉末は、炭化珪素質セラミックス粉末である。これに、バインダとしてヒドロキシプロピルメチルセルロース、造孔材として吸水性樹脂を添加すると共に、水を添加して成形原料とした。得られた成形原料を真空土練機により混練し、円柱状の坏土を作製した。ここで、炭化珪素粉末と金属珪素粉末とを合わせて(総称して)、「セラミックス原料」と称することがある。また、4H型炭化珪素結晶の含有率が0.1質量%の炭化珪素粉末が、「低4H型炭化珪素粉末」である。そして、4H型炭化珪素結晶の含有率が26.0質量%の炭化珪素粉末が、「高4H型炭化珪素粉末」である。バインダの含有量はセラミックス原料全体を100質量部としたときに7質量部であった。また、造孔材の含有量はセラミックス原料全体を100質量部としたときに3質量部であった。また、水の含有量はセラミックス原料全体を100質量部としたときに42質量部であった。炭化珪素粉末の平均粒子径は30μmであり、金属珪素粉末の平均粒子径は6μmであった。また、造孔材の平均粒子径は、25μmであった。炭化珪素粉末、金属珪素粉末及び造孔材の平均粒子径は、レーザー回折法で測定した値である。
ハニカム構造体(炭化珪素質セラミックス)から、4mm×2mm×40mmの試験片を切り出し、4端子法により抵抗値を測定する。抵抗値は、20℃で測定し、更に、100℃から800℃まで、100℃毎に測定する。得られた抵抗値より、比抵抗を算出する。
炭化珪素の結晶多形の定量は、粉末試料のX線回折法(Ruskaの方法(J.Mater.Sci.,14,2013-2017(1979)))で行う。
「比抵抗の測定」において、比抵抗の値が最小となる温度を「最小比抵抗となる温度(TR-Min)」とする。
通電時の安定性は、600Vで通電した時の担体内の温度分布を、熱電対を用いて測定し(ハニカム構造体内を、均等に39箇所、温度測定する。)、担体内の平均温度が500℃に達した時の温度分布を求めることにより、評価した。
耐熱性は、上記「通電時の安定性」の試験と同様にして、担体内の平均温度が500℃に達するまで、600Vでの通電を行い、500℃に達した後に通電を止めて50℃まで冷却する。この昇温、冷却を1サイクルとし、このサイクルを100サイクル繰り返した後の3C型炭化珪素結晶の転移率を求めることにより、評価した。3C型炭化珪素結晶の転移率は、耐熱試験前の3C型炭化珪素結晶の含有率から耐熱性試験後の3C型炭化珪素結晶の含有率を引いた値を、耐熱試験前の3C型炭化珪素結晶の含有率で除して、得られた値を100倍した値である。
製造条件の一部を表1に示すように変更した以外は、実施例1と同様にしてハニカム構造体(炭化珪素質セラミックス)を作製した。得られたハニカム構造体について、上記方法で「比抵抗」の測定を行った。結果を表2に示す。尚、表1において、「低4H型炭化珪素粉末」の「含有率(質量%)」の欄は、炭化珪素粉末全体と金属珪素の合計に対する、「低4H型炭化珪素粉末」の含有率を示す。また、「高4H型炭化珪素粉末」の「含有率(質量%)」の欄は、炭化珪素粉末全体と金属珪素の合計に対する、「高4H型炭化珪素粉末」の含有率を示す。「低4H型炭化珪素粉末」の「結晶構造比率(質量%)」の欄は、低4H型炭化珪素粉末中の炭化珪素結晶全体に対する、各結晶構造(4H型炭化珪素結晶、6H型炭化珪素結晶等)の比率(質量%)を示す。また、「高4H型炭化珪素粉末」の「結晶構造比率(質量%)」の欄は、高4H型炭化珪素粉末中の炭化珪素結晶全体に対する、各結晶構造(4H型炭化珪素結晶、6H型炭化珪素結晶等)の比率(質量%)を示す。また、金属珪素の含有率(質量%)は、炭化珪素粉末全体と金属珪素の合計に対する金属珪素の含有率を示す。また、造孔材の含有量は、「炭化珪素粉末全体と金属珪素の合計」を100質量部としたときの、含有比(質量部)で示している。
Claims (8)
- 炭化珪素結晶を含有し、
前記炭化珪素結晶中に、0.1~25質量%の4H型炭化珪素結晶、及び50~99.9質量%の6H型炭化珪素結晶が含有される炭化珪素質セラミックス。 - 窒素の含有量が0.01質量%以下である請求項1に記載の炭化珪素質セラミックス。
- 前記炭化珪素結晶を含有する複数の炭化珪素粒子と、前記炭化珪素粒子同士を結合させる珪素とを含有し、
前記珪素の含有率が10~40質量%である請求項1又は2に記載の炭化珪素質セラミックス。 - 前記炭化珪素粒子の平均粒子径が、10~50μmである請求項3に記載の炭化珪素質セラミックス。
- 気孔率が30~65%である請求項1~4のいずれかに記載の炭化珪素質セラミックス。
- 前記炭化珪素結晶中に、15R型炭化珪素結晶が0.1~20質量%含有される請求項1~5のいずれかに記載の炭化珪素質セラミックス。
- 請求項1~6のいずれかに記載の炭化珪素質セラミックスを材質とするハニカム構造体。
- 請求項7に記載のハニカム構造体を備え、通電により発熱する通電発熱性触媒担体。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP11829302.6A EP2623482B1 (en) | 2010-09-29 | 2011-09-29 | Silicon carbide ceramic and honeycomb structure |
CN201180047346.1A CN103140455B (zh) | 2010-09-29 | 2011-09-29 | 碳化硅质陶瓷以及蜂窝构造体 |
JP2012536563A JP5883795B2 (ja) | 2010-09-29 | 2011-09-29 | 炭化珪素質セラミックス及びハニカム構造体 |
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JP2016086644A (ja) * | 2014-10-29 | 2016-05-23 | 京セラ株式会社 | 釣り糸用ガイド部材 |
JP2019173663A (ja) * | 2018-03-28 | 2019-10-10 | 日本碍子株式会社 | ハニカム構造体 |
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WO2012043752A1 (ja) | 2010-09-29 | 2012-04-05 | 日本碍子株式会社 | 炭化珪素質セラミックスの製造方法及びハニカム構造体の製造方法 |
CN104118842B (zh) * | 2014-07-02 | 2017-01-18 | 上海师范大学 | 碳化硅介孔阵列材料及其制备方法 |
JP2022142543A (ja) * | 2021-03-16 | 2022-09-30 | 日本碍子株式会社 | ハニカム構造体及び電気加熱式担体 |
JP2022148668A (ja) | 2021-03-24 | 2022-10-06 | 日本碍子株式会社 | ハニカム構造体、ならびに該ハニカム構造体を用いた電気加熱式担体および排ガス処理装置 |
CN115814709A (zh) * | 2021-09-17 | 2023-03-21 | 中国石油化工股份有限公司 | 一种甲烷氧化制乙烯反应器 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61423A (ja) * | 1984-03-31 | 1986-01-06 | Ibiden Co Ltd | 炭化珪素質焼結体のフイルタ− |
JPH0753265A (ja) | 1993-08-12 | 1995-02-28 | Tokai Konetsu Kogyo Co Ltd | 導電性炭化珪素質セラミック材 |
JPH0789764A (ja) | 1993-09-21 | 1995-04-04 | Tokai Konetsu Kogyo Co Ltd | 炭化珪素発熱体 |
WO2006112052A1 (ja) * | 2005-03-30 | 2006-10-26 | Ibiden Co., Ltd. | 炭化珪素含有粒子、炭化珪素質焼結体を製造する方法、炭化珪素質焼結体、及びフィルター |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH061423A (ja) * | 1991-12-09 | 1994-01-11 | Nippon Daina Paato Kk | チップ整列分離装置 |
JP4246802B2 (ja) * | 1995-08-22 | 2009-04-02 | 東京窯業株式会社 | ハニカム構造体とその製造方法及び用途、並びに加熱装置 |
JP3642836B2 (ja) * | 1995-09-06 | 2005-04-27 | 東京窯業株式会社 | 炭化珪素ハニカム構造体及びその製造方法 |
US6762140B2 (en) * | 2001-08-20 | 2004-07-13 | Saint-Gobain Ceramics & Plastics, Inc. | Silicon carbide ceramic composition and method of making |
US7387657B2 (en) * | 2002-10-07 | 2008-06-17 | Ibiden Co., Ltd. | Honeycomb structural body |
EP1538133B1 (en) * | 2003-06-23 | 2018-01-10 | Ibiden Co., Ltd. | Honeycomb structure |
JP4812316B2 (ja) * | 2005-03-16 | 2011-11-09 | イビデン株式会社 | ハニカム構造体 |
JP2010190124A (ja) * | 2009-02-18 | 2010-09-02 | Toyota Industries Corp | 排ガス浄化装置 |
-
2011
- 2011-09-29 EP EP11829302.6A patent/EP2623482B1/en active Active
- 2011-09-29 WO PCT/JP2011/072432 patent/WO2012043749A1/ja active Application Filing
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2013
- 2013-03-27 US US13/851,438 patent/US8859075B2/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61423A (ja) * | 1984-03-31 | 1986-01-06 | Ibiden Co Ltd | 炭化珪素質焼結体のフイルタ− |
JPH0753265A (ja) | 1993-08-12 | 1995-02-28 | Tokai Konetsu Kogyo Co Ltd | 導電性炭化珪素質セラミック材 |
JPH0789764A (ja) | 1993-09-21 | 1995-04-04 | Tokai Konetsu Kogyo Co Ltd | 炭化珪素発熱体 |
WO2006112052A1 (ja) * | 2005-03-30 | 2006-10-26 | Ibiden Co., Ltd. | 炭化珪素含有粒子、炭化珪素質焼結体を製造する方法、炭化珪素質焼結体、及びフィルター |
Non-Patent Citations (1)
Title |
---|
RUSKA, J. MATER. SCI., vol. 14, 1979, pages 2013 - 2017 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016086644A (ja) * | 2014-10-29 | 2016-05-23 | 京セラ株式会社 | 釣り糸用ガイド部材 |
JP2019173663A (ja) * | 2018-03-28 | 2019-10-10 | 日本碍子株式会社 | ハニカム構造体 |
JP6999470B2 (ja) | 2018-03-28 | 2022-01-18 | 日本碍子株式会社 | ハニカム構造体 |
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US8859075B2 (en) | 2014-10-14 |
EP2623482A4 (en) | 2015-04-29 |
JP5883795B2 (ja) | 2016-03-15 |
CN103140455A (zh) | 2013-06-05 |
US20130216768A1 (en) | 2013-08-22 |
EP2623482B1 (en) | 2018-06-27 |
JPWO2012043749A1 (ja) | 2014-02-24 |
EP2623482A1 (en) | 2013-08-07 |
CN103140455B (zh) | 2016-11-23 |
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