JP2018070409A - Inorganic porous sintered compact and method for producing the same - Google Patents
Inorganic porous sintered compact and method for producing the same Download PDFInfo
- Publication number
- JP2018070409A JP2018070409A JP2016211657A JP2016211657A JP2018070409A JP 2018070409 A JP2018070409 A JP 2018070409A JP 2016211657 A JP2016211657 A JP 2016211657A JP 2016211657 A JP2016211657 A JP 2016211657A JP 2018070409 A JP2018070409 A JP 2018070409A
- Authority
- JP
- Japan
- Prior art keywords
- inorganic
- porous sintered
- sintered body
- inorganic porous
- producing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Porous Artificial Stone Or Porous Ceramic Products (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
本発明は、無機多孔質焼結体および無機多孔質焼結体の製造方法に関する。 The present invention relates to an inorganic porous sintered body and a method for producing an inorganic porous sintered body.
従来より、炭化珪素等のセラミックスや金属からなる発熱体が知られており、係る発熱体は、棒状の発熱体の端部から通電することにより炉内に配置した発熱部から放熱し、被処理物を加熱処理して使用されている。
このような炭化珪素発熱体において、通常は炉外に配置される発熱体端部の熱伝導率が高いと電力損失が大きくなり、省エネルギー化を図り難くなることから、発熱体端部については、熱伝導性を下げる対応が望まれている。
Conventionally, a heating element made of ceramics or metal such as silicon carbide is known, and the heating element dissipates heat from the heating element arranged in the furnace by energizing from the end of the rod-shaped heating element, and is processed. It is used by heating the product.
In such a silicon carbide heating element, since the power loss is large when the thermal conductivity of the heating element end portion arranged outside the furnace is high, it is difficult to save energy. A countermeasure to lower the thermal conductivity is desired.
また、例えば、ローラーハースキルンを構成する棒状のローラーは、その端部がベアリング等を介して駆動装置に接続されており、係るローラー端部を回転させることによりキルン内に配置したローラー本体部を回転させている。
上記ローラーハースキルンにおいても、ローラー端部の熱伝導率が高くなるとローラー端部が熱を帯びてキルン内の温度が低下し易くなり、電力損失が生じて省エネルギー化を図り難くなることから、ローラー端部の熱伝導率を下げる対応が望まれるようになっている。
In addition, for example, the rod-shaped roller constituting the roller hearth kiln has its end connected to a drive device via a bearing or the like, and the roller main body disposed in the kiln by rotating the roller end is used. It is rotating.
Even in the above roller hearth kiln, if the thermal conductivity of the roller end becomes high, the roller end is heated and the temperature inside the kiln is liable to decrease, causing power loss and making it difficult to save energy. A countermeasure to lower the thermal conductivity of the end has been desired.
上述した炭化珪素発熱体等の発熱体の場合、発熱体端部の比抵抗を低減し、端部で消費される電力を低減することにより省エネルギー化を図る方法が考えられ、このように比抵抗が低減された発熱体端部として、出願人は、炭化珪素、炭素および窒化珪素の混合粉末からなる成形体を、珪素の存在下、１５０〜１５００Ｐａの圧力下で１４５０〜１７００℃で加熱して反応焼結することにより得られる炭化珪素発熱体端部を提案するに至っている（特許文献１（特開２０１０−１２６４２７号公報））。 In the case of a heating element such as the above-described silicon carbide heating element, a method for reducing energy consumption by reducing the specific resistance at the end of the heating element and reducing the power consumed at the end can be considered. As an end portion of the heating element with reduced resistance, the applicant heated a molded body made of a mixed powder of silicon carbide, carbon and silicon nitride at 1450 to 1700 ° C. under a pressure of 150 to 1500 Pa in the presence of silicon. A silicon carbide heating element end obtained by reactive sintering has been proposed (Patent Document 1 (Japanese Patent Laid-Open No. 2010-126427)).
一方、本発明者等が検討したところ、発熱体端部は元来より比抵抗が小さな材料で構成されており、特許文献１記載の方法のみでは近年益々高まりつつある省エネルギー化の要望に対し、必ずしも十分に応えられないことが判明した。
また、発熱体端部のみならずローラー端部の構成材料としても、さらに省エネルギー化を図り得るものが求められるようになっている。
On the other hand, when the present inventors examined, the end of the heating element was originally composed of a material having a small specific resistance, and in response to the demand for energy saving that has been increasing in recent years only by the method described in Patent Document 1, It turned out that it was not always enough.
Moreover, what can aim at further energy saving is calculated | required also as a constituent material of not only a heat generating body edge part but a roller edge part.
このような状況下、本願発明者等は、セラミックスや金属の多孔質体に着目するに至った。 Under such circumstances, the inventors of the present application have focused on ceramics and metal porous bodies.
セラミックスや金属の多孔質体は、セラミックスや金属自体が緻密な材料であるにも拘わらず内部に多数の空孔を有することから、軽量で熱容量も小さく、さらに空孔の熱伝導性は一般的にセラミックスや金属等よりも低くなるため、省エネルギー化が求められる用途では有効な材料として使用し得ることが期待された。 Ceramics and metal porous bodies have many pores inside despite the fact that ceramics and metals themselves are dense materials, so they are lightweight and have a small heat capacity, and the thermal conductivity of the pores is common. It is expected that it can be used as an effective material in applications requiring energy saving.
上記多孔質体としては、例えば、ポリウレタンフォームをセラミックススラリー中に浸漬させてセラミックスを付着させた後に、ポリウレタンを消失させて作製されたものが考えられる。
また、セラミックススラリー中に発泡剤を添加して発泡させた後、凍結凝固させたり、固化材を添加して固めたり、そのまま石膏型等に流し込んで固めたものも考えられる。
しかしながら、本願発明者等が検討したところ、上記ポリウレタンフォームや発泡剤を使用した多孔質体は、空孔の形状が一様でなく、空孔のサイズや空孔量のばらつきが大きいことから、均質な材料が得られ難いことが判明した。
As the porous body, for example, one produced by immersing a polyurethane foam in a ceramic slurry and adhering the ceramic and then disappearing the polyurethane can be considered.
In addition, it is also conceivable that the ceramic slurry is foamed by adding a foaming agent and then freeze-solidified, solidified by adding a solidifying material, or poured into a plaster mold or the like as it is.
However, when the inventors of the present application examined, the porous body using the polyurethane foam and the foaming agent is not uniform in the shape of the pores, and the variation in the size and the amount of the pores is large. It turned out that a homogeneous material was difficult to obtain.
また、上記多孔質体として、セラミックス粉末と、おが屑、コーヒー豆の絞りかす、くるみ粉のような有機物とを混合し、焼成、成形したものが考えられ、この場合、焼成過程で有機物が消失することによって空孔が形成されるが、本発明者等が検討したところ、上記方法と同様に空孔のサイズや空孔量のばらつきが大きく、その調節が困難であることから、均質な材料が得られ難いことが判明した。 Further, as the porous body, ceramic powder and organic matter such as sawdust, coffee bean residue, and walnut powder may be mixed, baked and molded. In this case, the organic matter disappears during the firing process. As a result of the study by the present inventors, there was a large variation in the size and amount of pores as in the above method, and it was difficult to adjust the pores. It turned out to be difficult to obtain.
さらに、上記ポリウレタンフォームや有機物に代えてシリコーン樹脂粒子や有機マイクロバルーンを使用して空孔サイズを調節することも考えられたが、本願発明者等が検討したところ、一般にセラミックスと比較してシリコーン樹脂粒子や有機マイクロバルーンの比重は大きく異なり、例えばセラミックス粉末と比較して直径が０．１ｍｍ程度以上の球形のシリコーン樹脂粒子や有機マイクロバルーンはあまりにも大きいため、均一に混合することができず、空孔量のばらつきが大きく、均質な材料が得られ難いことが判明した。 Furthermore, it was considered that the pore size could be adjusted by using silicone resin particles or organic microballoons instead of the polyurethane foam or the organic material. The specific gravity of resin particles and organic microballoons varies greatly. For example, spherical silicone resin particles and organic microballoons with a diameter of about 0.1 mm or more compared to ceramic powder are too large to be mixed uniformly. It was found that the variation in the amount of pores was large and it was difficult to obtain a homogeneous material.
このような状況下、本発明は、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体および係る無機多孔質焼結体を簡便に製造する方法を提供することを目的とするものである。 Under such circumstances, the present invention has an inorganic porous sintered body having sufficient strength, suppressed variation in pore size and amount of pores, and suppressed thermal conductivity, and such inorganic porous sintered body It aims at providing the method of manufacturing a body simply.
上記目的を達成するために、本願発明者等が鋭意検討を行った結果、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０.７５〜１．００である空孔を有するとともに、四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９５〜１０５％である無機多孔質焼結体およびその製造方法により、上記目的を達成し得ることを見出し、本知見に基づいて本発明を完成するに至った。 In order to achieve the above object, the inventors of the present invention have conducted intensive studies. As a result, the average diameter is 0.1 to 2.0 mm, and the roundness represented by the average value of the minor axis / major axis is 0.75 to When having 1.00 holes and dividing into four constituent parts, (maximum value or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 The present inventors have found that the above object can be achieved by an inorganic porous sintered body having a bulk density variation of 95 to 105% and a method for producing the same, and have completed the present invention based on this finding.
すなわち、本発明は、
（１）平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である中空状無機焼結物を内部に複数含有するとともに、
四つの構成部に分割したときに、下記式
（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００
で表される嵩密度のばらつきが９５〜１０５％である
ことを特徴とする無機多孔質焼結体、
（２）前記中空状無機焼結物間の空隙にさらに無機焼結物を含有する上記（１）に記載の無機多孔質焼結体、
（３）上記（１）に記載の無機多孔質焼結体を製造する方法であって、
平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、所望の形状に成形し、
前記有機物質製球状物を除去する脱脂工程を施した後、
焼成処理して焼結体を形成する焼成工程を施す
ことを特徴とする無機多孔質焼結体の製造方法（以下、適宜、本発明に係る無機多孔質焼結体の製法１と称する）、
（４）前記コート顆粒が前記脱脂工程前に予め分級処理されたものである上記（３）に記載の無機多孔質焼結体の製造方法、
（５）前記無機粉末コーティング層の平均厚みおよび有機物質製球状物の平均直径が、
前記無機粉末コーティング層の平均厚み／前記有機物質製球状物の平均直径≧０．１の関係を満たす上記（３）または（４）に記載の無機多孔質焼結体の製造方法、
（６）前記無機粉末コーティング層を構成する無機粉末が、セラミックスおよび金属から選ばれる一種以上である上記（３）〜（５）のいずれかに記載の無機多孔質焼結体の製造方法、
（７）上記（２）に記載の無機多孔質焼結体を製造する方法であって、
平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、所望の形状に成形し、
前記有機物質製球状物を除去する脱脂工程を施した後、
前記脱脂工程によって生じた中空状無機焼結物間の空隙に無機物質の溶融物を含浸させる含浸工程を施す
ことを特徴とする無機多孔質焼結体の製造方法（以下、適宜、本発明に係る無機多孔質焼結体の製法２と称する）、
（８）前記コート顆粒が前記脱脂工程前に予め分級処理されたものである上記（７）に記載の無機多孔質焼結体の製造方法、
（９）前記無機粉末コーティング層の平均厚みおよび有機物質製球状物の平均直径が、
前記無機粉末コーティング層の平均厚み／前記有機物質製球状物の平均直径≧０．１の関係を満たす上記（７）または（８）に記載の無機多孔質焼結体の製造方法、
（１０）前記無機粉末コーティング層を形成する無機粉末または中空状無機焼結物間の空隙に含浸させる無機物質が、セラミックスおよび金属から選ばれる一種以上である上記（７）〜（９）のいずれかに記載の無機多孔質焼結体の製造方法、
を提供するものである。
That is, the present invention
(1) A plurality of hollow inorganic sintered products having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00 are contained therein. With
When divided into four components, the following formula (maximum value or minimum value of the bulk density of each component / average value of the bulk density of the four components) × 100
An inorganic porous sintered body characterized in that the variation in the bulk density represented by is 95 to 105%,
(2) The inorganic porous sintered body according to (1), further including an inorganic sintered product in a gap between the hollow inorganic sintered products,
(3) A method for producing the inorganic porous sintered body according to (1) above,
Coated granule having an inorganic powder coating layer on a spherical product made of an organic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00 For the desired shape,
After performing a degreasing step for removing the organic material spherical product,
A method for producing an inorganic porous sintered body characterized by performing a firing step of forming a sintered body by firing treatment (hereinafter, referred to as “Inorganic porous sintered body production method 1 according to the present invention as appropriate”),
(4) The method for producing an inorganic porous sintered body according to the above (3), wherein the coated granule is pre-classified before the degreasing step,
(5) The average thickness of the inorganic powder coating layer and the average diameter of the organic material spherical product are:
The method for producing an inorganic porous sintered body according to the above (3) or (4), which satisfies the relationship: average thickness of the inorganic powder coating layer / average diameter of the organic material spherical product ≧ 0.1,
(6) The method for producing an inorganic porous sintered body according to any one of (3) to (5), wherein the inorganic powder constituting the inorganic powder coating layer is at least one selected from ceramics and metals.
(7) A method for producing the inorganic porous sintered body according to (2) above,
Coated granule having an inorganic powder coating layer on a spherical product made of an organic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00 For the desired shape,
After performing a degreasing step for removing the organic material spherical product,
A method for producing an inorganic porous sintered body characterized in that an impregnation step of impregnating a gap between hollow inorganic sintered products produced by the degreasing step with a melt of an inorganic substance is performed (hereinafter referred to as appropriate in the present invention). This is called manufacturing method 2 of the inorganic porous sintered body).
(8) The method for producing an inorganic porous sintered body according to the above (7), wherein the coated granule is pre-classified before the degreasing step,
(9) The average thickness of the inorganic powder coating layer and the average diameter of the organic material spherical product are
The method for producing an inorganic porous sintered body according to the above (7) or (8), which satisfies a relationship of an average thickness of the inorganic powder coating layer / an average diameter of the organic material spherical product ≧ 0.1,
(10) Any of the above (7) to (9), wherein the inorganic substance impregnated in the voids between the inorganic powder or the hollow inorganic sintered material forming the inorganic powder coating layer is at least one selected from ceramics and metals A method for producing an inorganic porous sintered body according to claim 1,
Is to provide.
本発明によれば、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体および係る無機多孔質焼結体を簡便に製造する方法を提供することができる。 According to the present invention, an inorganic porous sintered body having sufficient strength, suppressed variation in pore size and amount of pores, and suppressed thermal conductivity, and such an inorganic porous sintered body can be simply obtained. A method of manufacturing can be provided.
先ず、本発明に係る無機多孔質焼結体について説明する。
本発明に係る無機多孔質焼結体は、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である中空状無機焼結物を内部に複数含有するとともに、
四つの構成部に分割したときに、下記式
（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００
で表される嵩密度のばらつきが９５〜１０５％である
ことを特徴とするものである。
First, the inorganic porous sintered body according to the present invention will be described.
The inorganic porous sintered body according to the present invention is a hollow inorganic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00. While containing multiple sintered products inside,
When divided into four components, the following formula (maximum value or minimum value of the bulk density of each component / average value of the bulk density of the four components) × 100
The variation in the bulk density represented by the formula is 95 to 105%.
本発明に係る無機多孔質焼結体は、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である中空状無機焼結物（空孔）を有している。 The inorganic porous sintered body according to the present invention is a hollow inorganic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00. It has a sintered product (holes).
上記中空状無機焼結物（空孔）の直径は、０．１〜２．０ｍｍであり、０．２〜１ｍｍであることが好ましく、０．３〜０．７ｍｍであることがより好ましい。 The hollow inorganic sintered product (holes) has a diameter of 0.1 to 2.0 mm, preferably 0.2 to 1 mm, and more preferably 0.3 to 0.7 mm.
上記中空状無機焼結物の平均直径が０．１ｍｍ未満である場合には、多孔体形状を作製し難くなり、また、上記中空状無機焼結物（空孔）の直径が２．０ｍｍ超である場合には、上記中空状無機焼結物（空孔）に割れや亀裂が生じ易くなって所望の強度を発揮し難くなる。
なお、本出願書類において、上記中空状無機焼結物（空孔）の直径とは、本発明に係る無機多孔質焼結体の断面を光学顕微鏡で観察したときの空孔の長径を意味し、上記中空状無機焼結物（空孔）の平均直径は、本発明に係る無機多孔質焼結体の断面を光学顕微鏡で観察したとき５０個の空孔の長径の算術平均値を意味する。
When the average diameter of the hollow inorganic sintered product is less than 0.1 mm, it becomes difficult to produce a porous body shape, and the diameter of the hollow inorganic sintered product (holes) exceeds 2.0 mm. In this case, cracks and cracks are likely to occur in the hollow inorganic sintered product (holes), making it difficult to exhibit the desired strength.
In the present application documents, the diameter of the hollow inorganic sintered product (hole) means the long diameter of the hole when the cross section of the inorganic porous sintered body according to the present invention is observed with an optical microscope. The average diameter of the hollow inorganic sintered product (holes) means the arithmetic average value of the long diameters of 50 holes when the cross section of the inorganic porous sintered body according to the present invention is observed with an optical microscope. .
上記「中空状無機焼結物の短径／中空状無機焼結物の長径」の平均値で表される真円度は、０．７５〜１．００であり、０．８〜１．００であるものが好ましく、０．９〜１．００であるものがより好ましい。
なお、本出願書類において、「中空状無機焼結物（空孔）の短径／中空状無機焼結物（空孔）の長径」の平均値で表される真円度は、本発明に係る無機多孔質焼結体の断面を光学顕微鏡で観察したときの５０個の中空状無機焼結物（空孔）の短径／長径の算術平均値を意味する。
The roundness represented by the average value of the above-mentioned “short diameter of hollow inorganic sintered product / long diameter of hollow inorganic sintered product” is 0.75 to 1.00, 0.8 to 1.00 What is is preferable and what is 0.9-1.00 is more preferable.
In the present application documents, the roundness represented by the average value of “the minor axis of the hollow inorganic sintered product (holes) / the major axis of the hollow inorganic sintered product (holes)” is included in the present invention. It means the arithmetic average value of the minor axis / major axis of 50 hollow inorganic sintered products (holes) when the cross section of the inorganic porous sintered body is observed with an optical microscope.
本発明に係る無機多孔質焼結体は、内部に存在する中空状無機焼結物（空孔）の直径および真円度が上記範囲内にあるものであることにより、その形状やサイズが略同等の球形状に統一され、このために焼結体内部における空孔のバラツキを抑制し、無機多孔質焼結体全体に亘ってその強度や熱伝導率を均一化しつつこれ等を所望範囲に容易に制御することができる。 Since the inorganic porous sintered body according to the present invention has a hollow inorganic sintered body (holes) having a diameter and roundness within the above range, the shape and size thereof are substantially reduced. The same spherical shape is unified, and for this reason, the dispersion of pores inside the sintered body is suppressed, and the strength and thermal conductivity are made uniform throughout the inorganic porous sintered body, and these are made within a desired range. It can be controlled easily.
また、上記中空状無機焼結物の外皮部分を構成する無機焼結物の平均厚みは、１０〜２，０００μｍであることが好ましく、３０〜１，６００μｍであることがより好ましく、５０〜１，４００μｍであることがさらに好ましい。 Moreover, it is preferable that the average thickness of the inorganic sintered material which comprises the outer skin part of the said hollow inorganic sintered material is 10-2,000 micrometers, It is more preferable that it is 30-1,600 micrometers, 50-1 More preferably, it is 400 μm.
上記中空状無機焼結物の外皮部分を構成する無機焼結物の平均厚みが上記範囲内にあることにより、中空状無機焼結物間の距離を所望範囲に容易に制御することができる。
なお、本出願書類において、上記中空状無機焼結物（空孔）の外皮部分を構成する無機焼結物の平均厚みは、本発明に係る無機多孔質焼結体の断面を光学顕微鏡で観察したときの５０箇所の厚みの平均値を意味する。
When the average thickness of the inorganic sintered product constituting the outer skin portion of the hollow inorganic sintered product is within the above range, the distance between the hollow inorganic sintered products can be easily controlled within a desired range.
In addition, in this application document, the average thickness of the inorganic sintered compact which comprises the outer skin part of the said hollow inorganic sintered compact (vacancy) is observing the cross section of the inorganic porous sintered compact concerning this invention with an optical microscope. It means the average value of the thickness of 50 places.
「中空状無機焼結物の外皮部分を構成する無機焼結物の平均厚み／中空状無機焼結物の平均直径」で表される比は、０．１以上が好ましく、０．２以上がより好ましく、０．３以上がさらに好ましい。上記中空状無機焼結物（空孔）の外皮部分に相当する無機焼結物の平均厚み／中空状無機焼結物（空孔）の平均直径で表される比の上限は特に制限されないが、通常、１．０以下が適当であり、０．８以下がより適当であり、０．７以下がさらに適当である。 The ratio represented by “average thickness of inorganic sintered product constituting the outer skin portion of hollow inorganic sintered product / average diameter of hollow inorganic sintered product” is preferably 0.1 or more, and preferably 0.2 or more. More preferred is 0.3 or more. The upper limit of the ratio represented by the average thickness of the inorganic sintered product corresponding to the outer skin portion of the hollow inorganic sintered product (holes) / the average diameter of the hollow inorganic sintered product (holes) is not particularly limited. Generally, 1.0 or less is appropriate, 0.8 or less is more appropriate, and 0.7 or less is more appropriate.
本発明に係る無機多孔質焼結体は、「中空状無機焼結物の外皮部分を構成する無機焼結物の平均厚み／中空状無機焼結物の平均直径」で表される比が０．１以上であることにより、中空状無機焼結物の外皮部分の割れや亀裂を抑制しつつ、優れた強度を容易に発揮することができる。 In the inorganic porous sintered body according to the present invention, the ratio represented by “average thickness of inorganic sintered body constituting outer skin portion of hollow inorganic sintered body / average diameter of hollow inorganic sintered body” is 0. By being 1 or more, it is possible to easily exhibit excellent strength while suppressing cracking and cracking of the outer skin portion of the hollow inorganic sintered product.
本発明に係る無機多孔質焼結体は、四つの構成部に分割したときに、下記式
（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００
で表される嵩密度のばらつきが９５〜１０５％であるものであり、９７〜１０３％であるものが好ましく、９８〜１０２％であるものがより好ましい。
When the inorganic porous sintered body according to the present invention is divided into four constituent parts, the following formula (maximum value or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100
The variation of the bulk density represented by the formula is 95 to 105%, preferably 97 to 103%, more preferably 98 to 102%.
本出願書類において、上記嵩密度のばらつきは、図１に示すように、本発明に係る無機多孔質焼結体１の深さ方向（無機多孔質焼結体１の製造時における上下方向）各長さが略均等になるように構成部ａ〜構成部ｄの四つの構成部に分割し、各構成部の嵩密度をアルキメデス法により求めるとともに四つの構成部の嵩密度の算術平均値を求めることにより算出することができる。 In the present application documents, the variation in the bulk density is as shown in FIG. 1 in the depth direction of the inorganic porous sintered body 1 according to the present invention (vertical direction during the production of the inorganic porous sintered body 1). Dividing into four constituent parts of constituent part a to constituent part d so that the lengths are substantially uniform, the bulk density of each constituent part is obtained by the Archimedes method and the arithmetic average value of the bulk densities of the four constituent parts is obtained. This can be calculated.
本発明に係る無機多孔質焼結体は、形状やサイズが略同等の球形状に統一され中空状無機焼結物（空孔）が全体に亘って均一に分散した、嵩密度のばらつきが抑制されたものであることから、その強度や熱伝導率を無機多孔質焼結体全体に亘って均一化しつつ中空状無機焼結物の含有量を制御することによりその強度や熱伝導率を容易に制御することができる。 The inorganic porous sintered body according to the present invention has a uniform spherical shape with almost the same shape and size, and the hollow inorganic sintered product (holes) is uniformly dispersed throughout the whole, suppressing the variation in bulk density. Therefore, the strength and thermal conductivity can be easily controlled by controlling the content of the hollow inorganic sintered product while making the strength and thermal conductivity uniform over the entire inorganic porous sintered body. Can be controlled.
本発明に係る中空状無機焼結物の構成材料は、セラミックスまたは金属であることが好ましい。
上記セラミックスとしては、ＳｉＣ、Ｓｉ３Ｎ４、Ａｌ２Ｏ３、ＳｉＯ２、ムライト、ＡｌＮ、粘度等から選ばれる一種以上を挙げることができる。
また、上記金属としては、鉄、アルミニウム、チタン、銅等から選ばれる一種以上を挙げることができる。
The constituent material of the hollow inorganic sintered product according to the present invention is preferably ceramics or metal.
Examples of the ceramic include one or more selected from SiC, Si 3 N 4 , Al 2 O 3 , SiO 2 , mullite, AlN, viscosity, and the like.
Moreover, as said metal, 1 or more types chosen from iron, aluminum, titanium, copper, etc. can be mentioned.
本発明に係る無機多孔質焼結体は、各種焼結方法で焼結されたものであってよく、例えば、反応焼結法、常圧焼結法、雰囲気加圧焼結法等により作製されたものを挙げることができる。
本発明に係る無機多孔質焼結体の好適な製造方法としては、後述する本発明に係る無機多孔質焼結体の製造方法を挙げることができる。
The inorganic porous sintered body according to the present invention may be sintered by various sintering methods, for example, produced by a reaction sintering method, a normal pressure sintering method, an atmospheric pressure sintering method, or the like. Can be mentioned.
As a suitable manufacturing method of the inorganic porous sintered body according to the present invention, a method for manufacturing the inorganic porous sintered body according to the present invention described later can be exemplified.
本発明に係る無機多孔質焼結体は、上記中空状無機焼結物間に空隙を有するものであってもよいし、上記中空状無機焼結物間の空隙にさらに無機焼結物を含有するものであってもよい。
上記中空状無機焼結物間の空隙にさらに含まれる無機焼結物としては、上記中空状無機焼結物の構成材料と同様の構成材料からなるものを挙げることができる。
本発明に係る無機多孔質焼結体が、上記中空状無機焼結物間の空隙にさらに無機焼結物を含有するものであることにより、所望の強度を容易に発揮することができる。
The inorganic porous sintered body according to the present invention may have voids between the hollow inorganic sintered materials, and further contains an inorganic sintered material in the voids between the hollow inorganic sintered materials. You may do.
Examples of the inorganic sintered product further included in the gaps between the hollow inorganic sintered products include those composed of the same constituent materials as the constituent materials of the hollow inorganic sintered product.
When the inorganic porous sintered body according to the present invention further contains an inorganic sintered product in the gap between the hollow inorganic sintered products, desired strength can be easily exhibited.
本発明に係る無機多孔質焼結体は、曲げ強度が、４０ＭＰａ以上であるものが好ましく、８０ＭＰａ以上であるものがより好ましく、１００〜１２０ＭＰａであるものがさらに好ましい。 The inorganic porous sintered body according to the present invention preferably has a bending strength of 40 MPa or more, more preferably 80 MPa or more, and still more preferably 100 to 120 MPa.
本出願書類において、無機多孔質焼結体の曲げ強度は、３点曲げ試験により測定した値を意味する。 In the present application document, the bending strength of the inorganic porous sintered body means a value measured by a three-point bending test.
本発明に係る無機多孔質焼結体は、その形状やサイズが略同等の球形状に統一され空孔が無機多孔質焼結体全体に亘って均一に分散したものであることから、局所的な強度の低下を抑制しつつ無機多孔質焼結体の強度を所望範囲に容易に制御することができる。 Since the inorganic porous sintered body according to the present invention has a uniform spherical shape with a uniform shape and size and pores are uniformly dispersed throughout the inorganic porous sintered body, It is possible to easily control the strength of the inorganic porous sintered body within a desired range while suppressing a significant decrease in strength.
本発明に係る無機多孔質焼結体は、熱伝導率が、１３０Ｗ／（ｍ・Ｋ）以下であるものが好ましく、１００Ｗ／（ｍ・Ｋ）以下であるものがより好ましく、９０Ｗ／（ｍ・Ｋ）以下であるものがさらに好ましい。
本出願書類において、無機多孔質焼結体の熱伝導率は、定常法（温度傾斜法）により測定した値を意味する。
The inorganic porous sintered body according to the present invention preferably has a thermal conductivity of 130 W / (m · K) or less, more preferably 100 W / (m · K) or less, and 90 W / (m -K) The following are more preferable.
In the present application document, the thermal conductivity of the inorganic porous sintered body means a value measured by a steady method (temperature gradient method).
本発明に係る無機多孔質焼結体は、その形状やサイズが略同等の球形状に統一され空孔が無機多孔質焼結体全体に亘って均一に分散したものであることから、無機多孔質焼結体の熱伝導率を所望範囲に容易に制御することができる。 Since the inorganic porous sintered body according to the present invention has a uniform shape and size of a spherical shape and the pores are uniformly dispersed throughout the inorganic porous sintered body, The thermal conductivity of the sintered compact can be easily controlled within a desired range.
本発明によれば、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体および係る無機多孔質焼結体を簡便に製造する方法を提供することができる。 According to the present invention, an inorganic porous sintered body having sufficient strength, suppressed variation in pore size and amount of pores, and suppressed thermal conductivity, and such an inorganic porous sintered body can be simply obtained. A method of manufacturing can be provided.
次に、本発明に係る無機多孔質焼結体の製造方法について説明する。
本発明に係る無機多孔質焼結体の製法１は、本発明の無機多孔質焼結体を製造する方法であって、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、前記有機物質製球状物を除去する脱脂工程を施した後、焼成処理して焼結体を形成する焼成工程を施すことを特徴とするものである。
また、本発明に係る無機多孔質焼結体の製法２は、本発明の無機多孔質焼結体を製造する方法であって、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、所望の形状に成形し、前記有機物質製球状物を除去する脱脂工程を施した後、前記脱脂工程によって生じた中空状無機焼結物間の空隙に無機物質の溶融物を含浸させる含浸工程を施すことを特徴とするものである。
本発明に係る無機多孔質焼結体の製法２は、中空状無機焼結物間の空隙にさらに無機焼結物を有する無機多孔質焼結体を製造する方法に関するものであって、脱脂処理工程後に焼成工程を施すことに代えて脱脂工程後に含浸工程を施すことを必須とするものである点において本発明に係る無機多孔質焼結体の製法１と相違するものの、その他の点においては本発明に係る無機多孔質焼結体の製法１の内容と共通することから、以下、本発明に係る無機多孔質焼結体の製法１および本発明に係る無機多孔質焼結体の製法２に共通する内容について説明した上で、各製法において特有の工程について説明するものとする。
Next, the manufacturing method of the inorganic porous sintered body according to the present invention will be described.
The method 1 for producing an inorganic porous sintered body according to the present invention is a method for producing the inorganic porous sintered body of the present invention, wherein the average diameter is 0.1 to 2.0 mm and the average value of the minor axis / major axis After applying a degreasing step for removing the organic material spherical product to the coated granule having an inorganic powder coating layer on the organic material spherical material having a roundness represented by 0.75 to 1.00 And a firing step of forming a sintered body by firing treatment.
In addition, manufacturing method 2 of the inorganic porous sintered body according to the present invention is a method for manufacturing the inorganic porous sintered body of the present invention, and has an average diameter of 0.1 to 2.0 mm and a minor axis / major axis. A coated granule having an inorganic powder coating layer on a spherical product made of organic material having a roundness expressed by an average value of 0.75 to 1.00, is molded into a desired shape, and the spherical product made of organic material After performing a degreasing process for removing slag, an impregnation process for impregnating a void between the hollow inorganic sintered products generated by the degreasing process with a melt of an inorganic substance is performed.
The method 2 for producing an inorganic porous sintered body according to the present invention relates to a method for producing an inorganic porous sintered body further having an inorganic sintered body in a space between hollow inorganic sintered bodies, and a degreasing treatment Although it differs from the manufacturing method 1 of the inorganic porous sintered body according to the present invention in that the impregnation step is essential after the degreasing step instead of the firing step after the step, in other points Since it is in common with the content of manufacturing method 1 of the inorganic porous sintered body according to the present invention, hereinafter, manufacturing method 1 of the inorganic porous sintered body according to the present invention and manufacturing method 2 of the inorganic porous sintered body according to the present invention are described below. In addition, after explaining the contents common to the above, specific steps in each manufacturing method will be explained.
本発明に係る無機多孔質焼結体の製造方法において、コート顆粒を構成する有機物質製球状物は、平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００であるものである。 In the method for producing an inorganic porous sintered body according to the present invention, a spherical product made of an organic substance constituting a coated granule has an average diameter of 0.1 to 2.0 mm and is represented by an average value of a minor axis / major axis. The circularity is 0.75 to 1.00.
上記有機物質製球状物の平均直径は、０．１〜２．０ｍｍであり、０．２〜１ｍｍであることが好ましく、０．３〜０．７ｍｍであることがより好ましい。 The average diameter of the organic material-made spherical product is 0.1 to 2.0 mm, preferably 0.2 to 1 mm, and more preferably 0.3 to 0.7 mm.
有機物質製球状物の平均直径が０．１ｍｍ未満である場合には、通常使用される無機粉末の粒径の差が小さくなって中空状無機焼結物（空孔）を形成し難くなる。
また、有機物質製球状物の平均直径が２．０ｍｍ超である場合には、脱脂時または焼結時に中空状無機焼結物（空孔）に割れや亀裂を生じ易くなる。
When the average diameter of the organic material-made spherical product is less than 0.1 mm, the difference in particle size of normally used inorganic powder is reduced, making it difficult to form a hollow inorganic sintered product (holes).
Further, when the average diameter of the organic material spherical product is more than 2.0 mm, cracks and cracks are likely to occur in the hollow inorganic sintered product (holes) during degreasing or sintering.
上記「有機物質製球状物の短径／有機物質製球状物の長径」の平均値で表される真円度は、０．７５〜１．００であり、０．９〜１．００であるものが好ましく、０．９５〜１．００であるものがより好ましい。 The roundness represented by the average value of the above-mentioned “short diameter of organic material spherical material / long diameter of organic material spherical material” is 0.75 to 1.00, and 0.9 to 1.00. A thing of 0.95-1.00 is more preferable.
本出願書類において、上記有機物質製球状物の平均直径は、標準篩で篩分したときの呼び寸法の中心値を意味する。
また、本出願書類において、「有機物質製球状物の短径／有機物質製球状物の長径」の平均値で表される真円度は、５０個の有機物質製球状物を光学顕微鏡で観察したときの有機物質製球状物の短径／長径の算術平均値を意味する。
In the present application document, the average diameter of the organic material spherical product means the center value of the nominal dimension when sieving with a standard sieve.
In addition, in this application document, the roundness represented by the average value of “the short diameter of the organic material spherical material / the long diameter of the organic material spherical material” is the observation of 50 organic material spherical materials with an optical microscope. It means the arithmetic mean value of the minor axis / major axis of the organic material spherical product.
本発明に係る無機多孔質焼結体の製造方法においては、有機物質製球状物の平均直径や、短径／長径の平均値で表される真円度が上記範囲内にあることにより、その形状やサイズが略同等の球形状に統一され、このために得られる焼結体内部における空孔のバラツキを抑制し、その強度や熱伝導率を無機多孔質焼結体全体に亘って均一化しつつ所望範囲に容易に制御することができる。 In the method for producing an inorganic porous sintered body according to the present invention, the average diameter of the organic material spherical product and the roundness represented by the average value of the minor axis / major axis are within the above range. The shape and size are unified into a substantially equivalent spherical shape, and the dispersion of pores inside the resulting sintered body is suppressed, and the strength and thermal conductivity are made uniform over the entire inorganic porous sintered body. However, the desired range can be easily controlled.
本発明に係る無機多孔質焼結体の製造方法において、有機物質製球状物を構成する有機物質としては、後述する無機粉末が焼結する温度未満の温度で消失するものであれば特に制限されないが、高分子製のものが好ましい。
有機物質製球状物として、具体的には、ポリプロピレン、アクリル樹脂、ナイロン、ポリアセタール、ポリカーボネイト、ポリスチレン等から選ばれる一種以上の高分子からなるものを挙げることができる。
また、有機物質製球状物は、中実状のものであってもよいし、中空状のものであってもよい。
In the method for producing an inorganic porous sintered body according to the present invention, the organic material constituting the organic material-made spherical product is not particularly limited as long as it disappears at a temperature lower than the temperature at which the inorganic powder described later is sintered. However, a polymer is preferable.
Specific examples of the spherical product made of an organic material include those made of one or more polymers selected from polypropylene, acrylic resin, nylon, polyacetal, polycarbonate, polystyrene, and the like.
Further, the organic material-made spherical product may be solid or hollow.
本発明に係る無機多孔質焼結体の製造方法において使用されるコート顆粒は、有機物質製球状物の表面に無機粉末コーティング層を有するものである。
無機粉末コーティング層を構成する無機粉末としては、製造対象となる無機多孔質焼結体の構成材料に応じて適宜決定すればよく、セラミックスまたは金属であることが好ましい。
上記セラミックスとしては、ＳｉＣ、Ｓｉ３Ｎ４、Ａｌ２Ｏ３、ＳｉＯ２、ムライト、ＡｌＮ、粘土等から選ばれる一種以上を挙げることができる。
また、上記金属としては、鉄、アルミニウム、チタン、銅等から選ばれる一種以上を挙げることができる。
The coated granules used in the method for producing an inorganic porous sintered body according to the present invention have an inorganic powder coating layer on the surface of a spherical product made of an organic substance.
What is necessary is just to determine suitably as an inorganic powder which comprises an inorganic powder coating layer according to the constituent material of the inorganic porous sintered compact used as manufacture object, and it is preferable that they are ceramics or a metal.
Examples of the ceramic include one or more selected from SiC, Si 3 N 4 , Al 2 O 3 , SiO 2 , mullite, AlN, clay, and the like.
Moreover, as said metal, 1 or more types chosen from iron, aluminum, titanium, copper, etc. can be mentioned.
本発明に係る無機多孔質焼結体の製造方法において、無機粉末コーティング層を構成する無機粉末は、平均粒径が、０．２〜１００μｍであるものが好ましく、０．２〜８０μｍであるものがより好ましく、０．２〜５０μｍであるものがさらに好ましい。 In the method for producing an inorganic porous sintered body according to the present invention, the inorganic powder constituting the inorganic powder coating layer preferably has an average particle size of 0.2 to 100 μm, preferably 0.2 to 80 μm. Is more preferable, and what is 0.2-50 micrometers is still more preferable.
なお、本出願書類において、無機粉末コーティング層を構成する無機粉末の平均粒径は、レーザー回折式粒度分布測定装置により測定された、体積積算粒度分布における積算粒度で５０％の粒径（平均粒径Ｄ５０）を意味する。 In the present application documents, the average particle size of the inorganic powder constituting the inorganic powder coating layer is 50% of the average particle size (average particle size) measured by a laser diffraction particle size distribution measuring device. Diameter D50).
本発明に係る無機多孔質焼結体の製造方法において、無機粉末コーティング層の平均厚みは、１０〜２，０００μｍであることが好ましく、３０〜１，６００μｍであることがより好ましく、５０〜１，４００μｍであることがさらに好ましい。
本発明に係る無機多孔質焼結体の製造方法において、無機粉末コーティング層の平均厚みが上記範囲内にあることにより、割れや亀裂の発生を抑制しつつ所望サイズの球状空孔を有する無機多孔質焼結体を容易に作製することができる。
In the method for producing an inorganic porous sintered body according to the present invention, the average thickness of the inorganic powder coating layer is preferably 10 to 2,000 μm, more preferably 30 to 1,600 μm, and 50 to 1 More preferably, it is 400 μm.
In the method for producing an inorganic porous sintered body according to the present invention, when the average thickness of the inorganic powder coating layer is within the above range, an inorganic porous material having spherical pores of a desired size while suppressing generation of cracks and cracks. A sintered material can be easily produced.
なお、本出願書類において、上記無機粉末コーティング層の平均厚みは、コーティング前の有機物質製球状物とコーティング後のコート顆粒を標準篩で篩分したときの呼び寸法の中心値の差を２分した値を意味する。 In the present application documents, the average thickness of the inorganic powder coating layer is the difference between the center value of the nominal dimensions when the spherical material made of organic material before coating and the coated granule after coating are sieved with a standard sieve by 2 minutes. Means the value.
本発明に係る無機多孔質焼結体の製造方法において、上記コート顆粒は、無機粉末コーティング層の平均厚み／有機物質製球状物の平均直径で表される比が０．１以上であるものが好ましく、０．２以上であるものがより好ましく、０．３以上であるものがさらに好ましい。
無機粉末コーティング層の平均厚み／有機物質製球状物の平均直径で表される比が０．１未満である場合には、後述する脱脂時または焼結時に割れや亀裂を生じ易くなる。
上記コート顆粒において、無機粉末コーティング層の平均厚み／有機物質製球状物の平均直径で表される比の上限は特に制限されないが、通常、１．０以下が適当であり、０．８以下がより適当であり、０．７以下がさらに適当である。
In the method for producing an inorganic porous sintered body according to the present invention, the coated granule has a ratio represented by an average thickness of the inorganic powder coating layer / an average diameter of the organic material spherical product of 0.1 or more. Preferably, it is 0.2 or more, more preferably 0.3 or more.
When the ratio represented by the average thickness of the inorganic powder coating layer / the average diameter of the organic material spheres is less than 0.1, cracks and cracks are likely to occur during degreasing or sintering described below.
In the above-mentioned coated granule, the upper limit of the ratio represented by the average thickness of the inorganic powder coating layer / the average diameter of the organic material spherical product is not particularly limited, but is usually 1.0 or less, and 0.8 or less is appropriate. More appropriate, 0.7 or less is more appropriate.
本発明に係る無機多孔質焼結体の製造方法において、コート顆粒は、成形・脱脂工程前に予め分級処理されたものであってもよく、この場合、得られる無機多孔質焼結体において、球状空孔のサイズのばらつきをより低減することができ、中空状無機焼結物（空孔）の存在量や分布が均一化された無機多孔質焼結体を容易に作製することができる。
上記分級処理は、篩分け法等、公知の方法を採用することができる。
In the method for producing an inorganic porous sintered body according to the present invention, the coated granule may be pre-classified before the molding / degreasing step. In this case, in the obtained inorganic porous sintered body, Variations in the size of the spherical pores can be further reduced, and an inorganic porous sintered body in which the abundance and distribution of the hollow inorganic sintered product (voids) are made uniform can be easily produced.
For the classification process, a known method such as a sieving method can be employed.
コート顆粒は、粒径が、１２０〜６，０００μｍであるものが好ましく、１６０〜５，２００μｍであるものがより好ましく、２００〜４，８００μｍであるものがさらに好ましい。 The coated granules preferably have a particle size of 120 to 6,000 μm, more preferably 160 to 5,200 μm, and even more preferably 200 to 4,800 μm.
コート顆粒の作製方法としては、有機物質製球状物が粘性を有するものであれば、有機物質製球状物上に所望量の無機粉末を振り掛けて作製することができ、有機物質製球状物が粘性を有さないものであれば、有機物質製球状物上に適宜有機バインダーを混合した所望量の無機粉末のスラリーを噴霧して作製したり、有機物質製球状物上に有機接着剤を塗布した上で所望量の無機粉末を振り掛けて作製することができる。 As a method for producing the coated granules, if the spherical material made of organic material has viscosity, it can be produced by sprinkling a desired amount of inorganic powder on the spherical material made of organic material. If it does not have, it is prepared by spraying a slurry of a desired amount of inorganic powder in which an organic binder is appropriately mixed on a spherical product made of organic material, or by applying an organic adhesive on the spherical product made of organic material It can be produced by sprinkling a desired amount of inorganic powder above.
本発明に係る無機多孔質焼結体の製造方法において、コート顆粒を構成する無機粉末コーティング層の平均厚み／有機物質製球状物の平均直径で表される比や、コート顆粒の平均粒径が上記範囲内にあることにより、所望サイズの球状空孔を所望割合で有する無機多孔質焼結体を容易に作製することができる。 In the method for producing an inorganic porous sintered body according to the present invention, the ratio represented by the average thickness of the inorganic powder coating layer constituting the coated granule / the average diameter of the organic material spherical product, or the average particle size of the coated granule By being in the said range, the inorganic porous sintered compact which has a spherical hole of desired size in a desired ratio can be produced easily.
本発明に係る無機多孔質焼結体の製造方法においては、上記コート顆粒に対し有機物質製球状物を除去する脱脂工程を施す。 In the method for producing an inorganic porous sintered body according to the present invention, a degreasing process for removing the spherical product made of an organic substance is performed on the coated granules.
脱脂工程は、通常、コート顆粒を不活性雰囲気下で加熱処理することにより実施することができるが、ＳｉＣなど非酸化性無機粉末をポリスチレンなど３００℃未満で熱分解する有機物質製球状物にコーティングした場合は、大気中でも脱脂することができる。 The degreasing process can usually be carried out by heat-treating the coated granules in an inert atmosphere, but non-oxidizing inorganic powder such as SiC is coated on a spherical product made of organic material that is thermally decomposed at less than 300 ° C. such as polystyrene. If it does, it can be degreased even in the atmosphere.
脱脂工程を不活性雰囲気下で施す場合、不活性雰囲気としては、窒素雰囲気やアルゴン雰囲気等の希ガス雰囲気等を挙げることができる。 When the degreasing step is performed in an inert atmosphere, examples of the inert atmosphere include a rare gas atmosphere such as a nitrogen atmosphere or an argon atmosphere.
脱脂工程における加熱温度は、有機物質製球状物が消失する温度以上であって無機粉末が焼結する温度未満の温度であれば特に制限されず、通常、２００〜７００℃が適当であり、２５０〜６５０℃がより適当であり、２８０〜６００℃がさらに適当である。
また、脱脂工程における加熱時間は、有機物質製球状物が消失する時間以上の時間であれば特に制限されず、３０〜７２００分間が適当であり、１２０〜３６００分間がより適当であり、３００〜１４４０分間がさらに適当である。
The heating temperature in the degreasing step is not particularly limited as long as it is not lower than the temperature at which the organic material spherical product disappears and is lower than the temperature at which the inorganic powder sinters. ˜650 ° C. is more appropriate, and 280 to 600 ° C. is more appropriate.
In addition, the heating time in the degreasing step is not particularly limited as long as it is a time longer than the time when the spherical product made of an organic material disappears, 30 to 7200 minutes is appropriate, 120 to 3600 minutes is more appropriate, and 300 to 1440 minutes is even more appropriate.
上記コート顆粒に対し有機物質製球状物を除去する脱脂工程を施し、有機物質製球状物をガス化して除去することにより、本発明に係る無機多孔質焼結体の製法１においては引き続く焼成工程において、また本発明に係る無機多孔質焼結体の製法２においては引き続く含浸工程において、ひび割れの発生等を抑制ししつつ簡便に無機多孔質焼結体を作製することができる。 The coating granule is subjected to a degreasing step for removing the organic material spherical product, and the organic material spherical product is removed by gasification, whereby the manufacturing method 1 of the inorganic porous sintered body according to the present invention continues the firing step. In addition, in the manufacturing method 2 of the inorganic porous sintered body according to the present invention, the inorganic porous sintered body can be easily produced while suppressing the occurrence of cracks and the like in the subsequent impregnation step.
本発明に係る無機多孔質焼結体の製法１においては、脱脂工程を施した後、焼成処理して焼結体を形成する焼成工程を施す。
焼成工程を不活性雰囲気下で施す場合、不活性雰囲気としては、窒素雰囲気やアルゴン雰囲気等の希ガス雰囲気等を挙げることができる。
In the manufacturing method 1 of the inorganic porous sintered body which concerns on this invention, after giving a degreasing process, the baking process which performs a baking process and forms a sintered compact is given.
In the case where the firing step is performed in an inert atmosphere, examples of the inert atmosphere include a rare gas atmosphere such as a nitrogen atmosphere or an argon atmosphere.
本発明に係る無機多孔質焼結体の製法１において、焼成工程における加熱温度は、無機粉末コーティング層由来の無機粉末が焼結する温度であれば特に制限されず、通常、１９００〜２２００℃が適当であり、１９５０〜２１５０℃がより適当であり、２０００〜２１００℃がさらに適当である。
また、焼成工程における加熱時間は、上記無機粉末コーティング層由来の無機粉末が焼結する時間以上の時間であれば特に制限されず、例えば、６０〜１８０分間が適当であり、９０〜１２０分間がより適当である。
In the manufacturing method 1 of the inorganic porous sintered body according to the present invention, the heating temperature in the firing step is not particularly limited as long as the inorganic powder derived from the inorganic powder coating layer is sintered, and is usually 1900 to 2200 ° C. It is suitable, 1950-2150 degreeC is more suitable, 2000-2100 degreeC is further suitable.
The heating time in the firing step is not particularly limited as long as the inorganic powder derived from the inorganic powder coating layer is sintered or longer. For example, 60 to 180 minutes is appropriate, and 90 to 120 minutes is appropriate. More appropriate.
本発明に係る無機多孔質焼結体の製法１においては、上記のとおり焼成工程において加熱、焼成して焼結処理するいわゆる常圧焼結処理を施すことにより、所望サイズの球状空孔を所望割合で有する無機多孔質焼結体を容易に作製することができる。 In the manufacturing method 1 of the inorganic porous sintered body according to the present invention, spherical pores of a desired size are obtained by applying so-called atmospheric pressure sintering treatment in which heating, firing and sintering are performed in the firing step as described above. An inorganic porous sintered body having a proportion can be easily produced.
本発明に係る無機多孔質焼結体の製法２においては、上記脱脂工程を施した後、当該脱脂工程によって生じた中空状無機焼結物間の空隙に無機物質の溶融物を含浸させる含浸工程を施す。 In the manufacturing method 2 of the inorganic porous sintered body according to the present invention, after performing the degreasing step, an impregnation step of impregnating a void between the hollow inorganic sintered products generated by the degreasing step with a melt of an inorganic substance. Apply.
本発明に係る無機多孔質焼結体の製法２において、球状空孔間の空隙に含浸させる無機物質としては、セラミックスおよび金属から選ばれる一種以上が好ましく、具体的には、上述した無機粉末コーティング層を構成する無機粉末の構成物質と同様のものや、それ等の構成元素等を挙げることができる。 In the production method 2 of the inorganic porous sintered body according to the present invention, the inorganic substance to be impregnated into the voids between the spherical pores is preferably one or more selected from ceramics and metals. Specifically, the inorganic powder coating described above Examples of the constituent material of the inorganic powder constituting the layer, and constituent elements thereof can be given.
本発明に係る無機多孔質焼結体の製法２において、含浸工程において含浸させる溶融物の温度は、無機粉末コーティング層由来の無機粉末や、含浸させる無機物質が溶融する温度であれば特に制限されず、例えば、ＳｉＣとＣのコーティング層にＳｉを含浸する場合、通常、１，４２０〜２,２００℃が適当であり、１，５００〜２,１００℃がより適当であり、１，５５０〜２,０５０℃がさらに適当である。
また、含浸工程における含浸処理時間は、上記無機粉末コーティング層由来の無機粉末や、含浸させる無機物質が脱脂工程によって生じた中空状無機焼結物間の空隙に充填可能な時間以上の時間であれば特に制限されず、例えば、ＳｉＣとＣのコーティング層にＳｉを含浸する場合、１０〜６００分間が適当であり、３０〜１８０分間がより適当である。
In the manufacturing method 2 of the inorganic porous sintered body according to the present invention, the temperature of the melt to be impregnated in the impregnation step is particularly limited as long as the inorganic powder derived from the inorganic powder coating layer or the temperature at which the inorganic substance to be impregnated melts. For example, when the SiC and C coating layer is impregnated with Si, usually 1,420 to 2,200 ° C. is appropriate, 1,500 to 2,100 ° C. is more appropriate, and 1,550 to 2,050 ° C is more suitable.
In addition, the impregnation time in the impregnation step may be longer than the time that the inorganic powder derived from the inorganic powder coating layer or the inorganic substance to be impregnated can be filled in the voids between the hollow inorganic sintered products generated by the degreasing step. For example, when the SiC and C coating layer is impregnated with Si, 10 to 600 minutes is appropriate, and 30 to 180 minutes is more appropriate.
本発明に係る無機多孔質焼結体の製法２においては、上記含浸工程において高温の無機物質の溶融物を含浸させて焼結処理することにより、所望サイズの球状空孔を所望割合で有する無機多孔質焼結体を容易に作製することができる。 In the manufacturing method 2 of the inorganic porous sintered body according to the present invention, an inorganic material having spherical pores of a desired size in a desired ratio is obtained by impregnating a high temperature inorganic substance melt in the impregnation step and performing a sintering treatment. A porous sintered body can be easily produced.
本発明によれば、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体を簡便に製造する方法を提供することができる。 ADVANTAGE OF THE INVENTION According to this invention, while providing sufficient intensity | strength, the dispersion | variation in the size of a void | hole or the amount of void | holes was suppressed, and the method to manufacture simply the inorganic porous sintered compact by which heat conductivity was suppressed is provided. it can.
以下、本発明を実施例および比較例によりさらに詳細に説明するが、本発明は以下の例により何ら限定されるものではない。 EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by the following examples.
（実施例１）
図２に示す平均直径０．３３ｍｍ[呼び径３５５μｍを通り、３００μｍを通らないもの]で、短径／長径の平均値で表される真円度が０．９５である中実状のポリスチレン球体に対し、ＳｉＣ粉末８０質量％、カーボン粉末１５質量％およびシリコン粉末５質量％を含む混合粉末を、糖衣コーティング装置（フロイント産業（株）製ＣＦグラニュレーター）を用いてコーティングすることにより、上記ポリスチレン球体上に無機粉末コーティング層を形成し、次いで篩分けすることにより、直径０．５〜０．６ｍｍのコート顆粒を作製した。得られたコート顆粒を図３に示す。
得られたコート顆粒は、無機粉末コーティング層の平均厚み／上記ポリスチレン球体の平均直径で表される比が０．３３であるものであった。
得られたコート顆粒を一軸成形した後、大気雰囲気下、２８０℃で３６０分間加熱処理することにより脱脂処理を施した。
次いで、上記脱脂工程によって生じた球状空孔間の空隙に、アルゴン雰囲気下で溶融シリコンを含浸し、コート顆粒表面のコーティング層を構成する無機粉末と反応焼結させることにより、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を得た。得られたＳｉＣ多孔質焼結体の切断面の顕微鏡写真を図４に示す。
得られたＳｉＣ多孔質焼結体は、短径／長径の平均値で表される真円度が０．９２である球状の空孔（図４に示す円形状の部位）を有し、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９９．１〜１００．９％で、曲げ強さが９１ＭＰａ、熱伝導率が８７Ｗ／（ｍ・Ｋ）であるものであった。
Example 1
A solid polystyrene sphere having an average diameter of 0.33 mm [passing through a nominal diameter of 355 μm and not passing through 300 μm] shown in FIG. 2 and having a roundness represented by an average value of the minor axis / major axis is 0.95. On the other hand, the above-mentioned polystyrene sphere is coated by coating a mixed powder containing 80% by mass of SiC powder, 15% by mass of carbon powder and 5% by mass of silicon powder using a sugar coating apparatus (CF granulator manufactured by Freund Sangyo Co., Ltd.). A coated granule having a diameter of 0.5 to 0.6 mm was prepared by forming an inorganic powder coating layer thereon and then sieving. The resulting coated granules are shown in FIG.
The obtained coated granules had a ratio expressed by the average thickness of the inorganic powder coating layer / the average diameter of the polystyrene spheres of 0.33.
The obtained coated granules were uniaxially molded, and then degreased by heat treatment at 280 ° C. for 360 minutes in an air atmosphere.
Next, the voids between the spherical pores generated by the above degreasing step are impregnated with molten silicon under an argon atmosphere, and reacted and sintered with inorganic powder constituting the coating layer on the surface of the coated granules, whereby a diameter of 50 mm and a height of A SiC porous sintered body having a cylindrical shape of 120 mm was obtained. The microscope picture of the cut surface of the obtained SiC porous sintered compact is shown in FIG.
The obtained SiC porous sintered body has spherical pores (circular portions shown in FIG. 4) having a roundness of 0.92 represented by the average value of the minor axis / major axis. When divided into four constituent parts as shown in FIG. 1, the bulk density variation represented by (maximum or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 Was 99.1 to 100.9%, the bending strength was 91 MPa, and the thermal conductivity was 87 W / (m · K).
（実施例２）
平均直径０．３３ｍｍで、短径／長径の平均値で表される真円度が０．９５である中実状のポリスチレン球体に代えて、平均直径０．３９ｍｍ[呼び径４２５μｍを通り、３５５μｍを通らないもの]で、短径／長径の平均値で表される真円度が０．９６である中実状のポリスチレン球体を用い、直径０．７１〜０．８５ｍｍのコート顆粒（無機粉末コーティング層の平均厚み／上記ポリスチレン球体の平均直径で表される比が０．５０であるもの）を作製し、係るコート顆粒を用いた以外は、実施例１と同様の方法により、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を得た。得られたＳｉＣ多孔質焼結体の切断面の顕微鏡写真を図５に示す。
得られたＳｉＣ多孔質焼結体は、短径／長径の平均値で表される真円度が０．９３である球状の空孔（図５に示す円形状の部位）を有し、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９８．８〜１００．５％で、曲げ強さが９０ＭＰａ、熱伝導率が８８Ｗ／（ｍ・Ｋ）であるものであった。
(Example 2)
Instead of a solid polystyrene sphere having an average diameter of 0.33 mm and a roundness represented by an average value of the minor axis / major axis of 0.95, an average diameter of 0.39 mm [passing through a nominal diameter of 425 μm and 355 μm Non-passable] using solid polystyrene spheres having a roundness of 0.96 represented by the average value of the minor axis / major axis, and coated granules (inorganic powder coating layer) having a diameter of 0.71 to 0.85 mm The ratio expressed by the average thickness of the polystyrene spheres and the ratio of the average diameter of the polystyrene spheres is 0.50), and the coated granules are used. A SiC porous sintered body having a cylindrical shape of 120 mm was obtained. The microscope picture of the cut surface of the obtained SiC porous sintered compact is shown in FIG.
The obtained SiC porous sintered body has spherical pores (circular portions shown in FIG. 5) having a roundness of 0.93 represented by the average value of the minor axis / major axis. When divided into four constituent parts as shown in FIG. 1, the bulk density variation represented by (maximum or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 Was 98.8 to 100.5%, the bending strength was 90 MPa, and the thermal conductivity was 88 W / (m · K).
（実施例３）
平均直径０．３３ｍｍで、短径／長径の平均値で表される真円度が０．９５ である中実状のポリスチレン球体に代えて、平均直径０．６０ｍｍ[呼び径７１０μｍを通り、５００μｍを通らないもの]で、短径／長径の平均値で表される真円度が０．９６である中実状のポリスチレン球体を用い、直径０．８５〜１０００ｍｍのコート顆粒（無機粉末コーティング層の平均厚み／上記ポリスチレン球体の平均直径で表される比が０．２７であるもの）を作製し、係るコート顆粒を用いた以外は、実施例１と同様の方法により、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を得た。得られたＳｉＣ多孔質焼結体の切断面の顕微鏡写真を図６に示す。
得られたＳｉＣ多孔質焼結体は、短径／長径の平均値で表される真円度が０．９４である球状の空孔（図６に示す円形状の部位）を有し、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９８．２〜１０１．２ ％で、曲げ強さが５０ＭＰａ、熱伝導率が８５Ｗ／（ｍ・Ｋ）であるものであった。
(Example 3)
Instead of a solid polystyrene sphere having an average diameter of 0.33 mm and a roundness represented by an average value of the minor axis / major axis of 0.95, an average diameter of 0.60 mm [passing through a nominal diameter of 710 μm, 500 μm Non-passable], using solid polystyrene spheres having a roundness of 0.96 represented by the average value of the short diameter / long diameter, and coated granules having a diameter of 0.85 to 1000 mm (average of the inorganic powder coating layer) Thickness / ratio expressed by the average diameter of the polystyrene spheres is 0.27), and the coated granule is used in the same manner as in Example 1 except that the diameter is 50 mm and the height is 120 mm. A SiC porous sintered body having a cylindrical shape was obtained. A photomicrograph of the cut surface of the obtained SiC porous sintered body is shown in FIG.
The obtained SiC porous sintered body has spherical pores (circular portions shown in FIG. 6) having a roundness of 0.94 represented by the average value of the minor axis / major axis. When divided into four constituent parts as shown in FIG. 1, the bulk density variation represented by (maximum or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 Was 98.2 to 101.2%, the bending strength was 50 MPa, and the thermal conductivity was 85 W / (m · K).
（実施例４）
平均直径０．３３ｍｍで、短径／長径の平均値で表される真円度が０．９５である中実状のポリスチレン球体に代えて、平均直径０．７２ｍｍ[呼び径８５０μｍを通り、６００μｍを通らないもの]で、短径／長径の平均値で表される真円度が０．９７である中実状のポリスチレン球体を用い、直径１．７〜２．０ｍｍのコート顆粒（無機粉末コーティング層の平均厚み／上記ポリスチレン球体の平均直径で表される比が０．７８であるもの）を作製し、係るコート顆粒を用いた以外は、実施例１と同様の方法により、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を得た。得られたＳｉＣ多孔質焼結体の切断面の顕微鏡写真を図７に示す。
得られたＳｉＣ多孔質焼結体は、短径／長径の平均値で表される真円度が０．９４である球状の空孔（図７に示す円形状の部位）を有し、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９９．０〜１０２．０ ％で、曲げ強さが８２ＭＰａ、熱伝導率が８７Ｗ／（ｍ・Ｋ）であるものであった。
Example 4
Instead of a solid polystyrene sphere having an average diameter of 0.33 mm and a roundness represented by an average value of the minor axis / major axis of 0.95, an average diameter of 0.72 mm [passing through a nominal diameter of 850 μm, 600 μm Non-passable] using solid polystyrene spheres having a roundness represented by an average value of the short diameter / long diameter of 0.97, and coated granules (inorganic powder coating layer) having a diameter of 1.7 to 2.0 mm The ratio expressed by the average thickness / the average diameter of the polystyrene spheres is 0.78), and the coated granule is used in the same manner as in Example 1 except that the diameter is 50 mm and the height. A SiC porous sintered body having a cylindrical shape of 120 mm was obtained. The microscope picture of the cut surface of the obtained SiC porous sintered compact is shown in FIG.
The obtained SiC porous sintered body has spherical pores (circular portions shown in FIG. 7) having a roundness of 0.94 represented by the average value of the minor axis / major axis. When divided into four constituent parts as shown in FIG. 1, the bulk density variation represented by (maximum or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 Was 99.0 to 102.0%, the bending strength was 82 MPa, and the thermal conductivity was 87 W / (m · K).
（実施例５）
平均直径０．５５ｍｍ[呼び径６００μｍを通り、５００μｍを通らないもの]で、短径／長径の平均値で表される真円度が０．９７である中実状のポリスチレン球体に対し、固形分換算で、平均直径０．８μｍのＳｉＣ粉末９６．７質量％、焼結助剤であるホウ素粉末０．３質量％および炭素粉末３質量％を含む混合スラリーを、糖衣コーティング装置（フロイント産業（株）製ＣＦグラニュレーター）を用いてコーティングすることにより、上記ポリスチレン球体上に無機粉末コーティング層を形成し、次いで篩分けすることにより、直径０．８５〜１．０ｍｍのコート顆粒を作製した。
得られたコート顆粒は、無機粉末コーティング層の平均厚み／上記ポリスチレン球体の平均直径で表される比が０．３４であるものであった。
得られたコート顆粒を一軸成形した後、大気雰囲気下、２８０℃で６００分間加熱処理することにより脱脂処理を施した。
次いで、Ａｒ雰囲気下において、２２００℃で１２０分間焼成して焼結処理を施すことにより、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を得た。得られたＳｉＣ多孔質焼結体の切断面の顕微鏡写真を図８に示す。
得られたＳｉＣ多孔質焼結体は、短径／長径の平均値で表される真円度が０．８５である球状の空孔（図８に示す円形状の部位）を有し、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９７．６〜１０２．０％、曲げ強さが８２ＭＰａ、熱伝導率が９０Ｗ／（ｍ・Ｋ）であるものであった。
(Example 5)
For solid polystyrene spheres having an average diameter of 0.55 mm [passing through nominal diameter of 600 μm and not passing through 500 μm] and having a roundness represented by the average value of the minor axis / major axis of 0.97, the solid content In terms of conversion, a mixed slurry containing 96.7% by mass of SiC powder having an average diameter of 0.8 μm, 0.3% by mass of boron powder as a sintering aid, and 3% by mass of carbon powder was applied to a sugar coating apparatus (Freund Sangyo Co., Ltd.). ) CF granulator) was used to form an inorganic powder coating layer on the polystyrene sphere, and then sieved to prepare coated granules having a diameter of 0.85 to 1.0 mm.
The obtained coated granules had a ratio represented by the average thickness of the inorganic powder coating layer / the average diameter of the polystyrene spheres of 0.34.
The obtained coated granules were uniaxially molded, and then degreased by heat treatment at 280 ° C. for 600 minutes in an air atmosphere.
Next, an SiC porous sintered body having a columnar shape with a diameter of 50 mm and a height of 120 mm was obtained by firing and sintering at 2200 ° C. for 120 minutes in an Ar atmosphere. A micrograph of the cut surface of the obtained SiC porous sintered body is shown in FIG.
The obtained SiC porous sintered body has spherical pores (circular portions shown in FIG. 8) having a roundness of 0.85 expressed by the average value of the minor axis / major axis. When divided into four constituent parts as shown in FIG. 1, the bulk density variation represented by (maximum or minimum value of bulk density of each constituent part / average value of bulk density of four constituent parts) × 100 Of 97.6 to 102.0%, bending strength of 82 MPa, and thermal conductivity of 90 W / (m · K).
（比較例１）
ＳｉＣ粉末８０質量％、カーボン粉末１５質量％およびシリコン粉末５質量％を含む混合粉末を、一軸成形した後、アルゴン雰囲気下で溶融シリコンを含浸し、反応焼結させることにより、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ焼結体を得た。得られたＳｉＣ焼結体は、図１に示すように四つの構成部に分割したときに、（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００で表される嵩密度のばらつきが９９．５〜１００．５％で、曲げ強さが１２５ＭＰａ、熱伝導率が１３３Ｗ／（ｍ・Ｋ）であるものであった。
(Comparative Example 1)
A mixed powder containing 80% by mass of SiC powder, 15% by mass of carbon powder and 5% by mass of silicon powder was uniaxially molded, then impregnated with molten silicon in an argon atmosphere, and subjected to reactive sintering, thereby obtaining a diameter of 50 mm and a height. A SiC sintered body having a 120 mm cylindrical shape was obtained. When the obtained SiC sintered body is divided into four constituent parts as shown in FIG. 1, (the maximum value or the minimum value of the bulk density of each constituent part / the average value of the bulk density of the four constituent parts) The variation in bulk density represented by x100 was 99.5 to 100.5%, the bending strength was 125 MPa, and the thermal conductivity was 133 W / (m · K).
（実施例６）
実施例１において、脱脂工程によって生じた球状空孔間の空隙に、アルゴン雰囲気下で溶融シリコンを含浸し、コート顆粒表面のコーティング層を構成する無機粉末と反応焼結させることにより、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ多孔質焼結体を作製することに代えて、直径２０ｍｍ、内径１１ｍｍ、長さ３００ｍｍの円管形状を有するＳｉＣ多孔質焼結体を２本作製した以外は、実施例１と同様の方法でＳｉＣ多孔質焼結体を作製した。
得られたＳｉＣ多孔質焼結体２本をＳｉＣ発熱部（長さ３００ｍｍ）の両端に各々溶接して、ＳｉＣ発熱体Ａとした。
ＳｉＣ発熱体Ａを電源に繋ぎ、ＳｉＣ発熱部中央の表面温度が１０００℃になるように電力を印加した。電力印加１０分後、ＳｉＣ発熱体Ａの端面の温度を測定して、放散熱量を、有限要素法を用いた解析ソフトにより算出したところ、端面温度２６４℃、放散熱量１５２Ｗであった。結果を表１に示す。
(Example 6)
In Example 1, the gap between the spherical pores generated by the degreasing process is impregnated with molten silicon under an argon atmosphere, and reacted and sintered with the inorganic powder constituting the coating layer on the surface of the coated granule. Instead of producing a SiC porous sintered body having a columnar shape with a height of 120 mm, two SiC porous sintered bodies having a circular pipe shape with a diameter of 20 mm, an inner diameter of 11 mm, and a length of 300 mm were produced. A SiC porous sintered body was produced in the same manner as in Example 1.
Two SiC porous sintered bodies thus obtained were welded to both ends of a SiC heat generating portion (length: 300 mm) to obtain SiC heat generating body A.
The SiC heating element A was connected to a power source, and power was applied so that the surface temperature at the center of the SiC heating part was 1000 ° C. Ten minutes after application of power, the temperature of the end face of the SiC heating element A was measured, and the amount of heat dissipated was calculated by analysis software using a finite element method. The end face temperature was 264 ° C. and the amount of heat dissipated was 152 W. The results are shown in Table 1.
（比較例２）
比較例１において、混合粉末の一軸成形物にアルゴン雰囲気下で溶融シリコンを含浸し、反応焼結させることにより、直径５０ｍｍ、高さ１２０ｍｍの円柱形状を有するＳｉＣ焼結体を作製することに代えて、直径２０ｍｍ、内径１１ｍｍ、長さ３００ｍｍの円管形状を有するＳｉＣ焼結体を２本作製した以外は、比較例１と同様の方法でＳｉＣ焼結体を作製した。
得られたＳｉＣ焼結体２本をＳｉＣ発熱部（長さ３００ｍｍ）の両端に各々溶接して、ＳｉＣ発熱体Ｂとした。
実施例６と同様にして、ＳｉＣ発熱体Ｂを電源に繋ぎ、ＳｉＣ発熱部中央の表面温度が１０００℃になるように電力を印加した。電力印加１０分後、ＳｉＣ発熱体Ｂの端面の温度を測定して、放散熱量を計算したところ、端面温度２９６℃、放散熱量１６９Ｗであった。結果を表１に示す。
(Comparative Example 2)
In Comparative Example 1, instead of producing a SiC sintered body having a columnar shape with a diameter of 50 mm and a height of 120 mm by impregnating a uniaxial molded product of mixed powder with molten silicon in an argon atmosphere and performing reaction sintering. A SiC sintered body was produced in the same manner as in Comparative Example 1 except that two SiC sintered bodies having a diameter of 20 mm, an inner diameter of 11 mm, and a length of 300 mm were produced.
Two obtained SiC sintered bodies were welded to both ends of a SiC heat generating portion (length: 300 mm), respectively, to obtain a SiC heat generating body B.
In the same manner as in Example 6, SiC heating element B was connected to a power source, and electric power was applied so that the surface temperature at the center of the SiC heating part was 1000 ° C. Ten minutes after the application of power, the temperature of the end face of the SiC heating element B was measured and the amount of heat dissipated was calculated. The end face temperature was 296 ° C. and the amount of heat dissipated was 169 W. The results are shown in Table 1.
実施例１〜実施例６によれば、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体を、簡便に製造できることが分かる。
また、表１より、実施例６で得られたＳｉＣ発熱体Ａは、比較例２で得られたＳｉＣ発熱体Ｂに比較して、端部が本発明に係る無機多孔質焼結体により構成されていることから、熱伝導率を低減することができ、このために比較例１で得られたＳｉＣ発熱体Ｂに対し約１０％放散熱量が低く省エネルギー化を図り得ることが分かる。
According to Examples 1 to 6, an inorganic porous sintered body that has sufficient strength, that is, the variation in the size of the pores and the amount of the pores is suppressed and the thermal conductivity is suppressed can be easily manufactured. I understand.
Further, from Table 1, the SiC heating element A obtained in Example 6 is composed of the inorganic porous sintered body according to the present invention at the end compared to the SiC heating element B obtained in Comparative Example 2. Therefore, it can be seen that the thermal conductivity can be reduced, and for this reason, about 10% of the heat dissipated in the SiC heating element B obtained in Comparative Example 1 is low and energy saving can be achieved.
本発明によれば、十分な強度を有するとともに、空孔のサイズや空孔量のばらつきが抑制され熱伝導率が抑制された無機多孔質焼結体および係る無機多孔質焼結体を簡便に製造する方法を提供することができる。 According to the present invention, an inorganic porous sintered body having sufficient strength, suppressed variation in pore size and amount of pores, and suppressed thermal conductivity, and such an inorganic porous sintered body can be simply obtained. A method of manufacturing can be provided.
Claims (10)
四つの構成部に分割したときに、下記式
（各構成部の嵩密度の最大値または最低値／四つの構成部の嵩密度の平均値）×１００
で表される嵩密度のばらつきが９５〜１０５％である
ことを特徴とする無機多孔質焼結体。 While containing a plurality of hollow inorganic sintered products having a roundness of 0.75 to 1.00 represented by an average value of minor axis / major axis with a diameter of 0.1 to 2.0 mm,
When divided into four components, the following formula (maximum value or minimum value of the bulk density of each component / average value of the bulk density of the four components) × 100
The inorganic porous sintered body is characterized in that the variation in the bulk density represented by the formula is 95 to 105%.
平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、所望の形状に成形し、
前記有機物質製球状物を除去する脱脂工程を施した後、
焼成処理して焼結体を形成する焼成工程を施す
ことを特徴とする無機多孔質焼結体の製造方法。 A method for producing the inorganic porous sintered body according to claim 1,
Coated granule having an inorganic powder coating layer on a spherical product made of an organic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00 For the desired shape,
After performing a degreasing step for removing the organic material spherical product,
A method for producing an inorganic porous sintered body, comprising performing a firing step of forming a sintered body by firing treatment.
前記無機粉末コーティング層の平均厚み／前記有機物質製球状物の平均直径≧０．１の関係を満たす請求項３または請求項４に記載の無機多孔質焼結体の製造方法。 The average thickness of the inorganic powder coating layer and the average diameter of the organic material spheres are:
The manufacturing method of the inorganic porous sintered compact of Claim 3 or Claim 4 satisfy | filling the relationship of the average thickness of the said inorganic powder coating layer / the average diameter of the said organic substance spherical material> 0.1.
平均直径が０．１〜２．０ｍｍで短径／長径の平均値で表される真円度が０．７５〜１．００である有機物質製球状物上に無機粉末コーティング層を有するコート顆粒に対し、所望の形状に成形し、
前記有機物質製球状物を除去する脱脂工程を施した後、
前記脱脂工程によって生じた中空状無機焼結物間の空隙に無機物質の溶融物を含浸させる含浸工程を施す
ことを特徴とする無機多孔質焼結体の製造方法。 A method for producing the inorganic porous sintered body according to claim 2,
Coated granule having an inorganic powder coating layer on a spherical product made of an organic material having an average diameter of 0.1 to 2.0 mm and a roundness represented by an average value of minor axis / major axis of 0.75 to 1.00 For the desired shape,
After performing a degreasing step for removing the organic material spherical product,
A method for producing an inorganic porous sintered body, comprising an impregnation step of impregnating a gap between hollow inorganic sintered products generated by the degreasing step with a melt of an inorganic substance.
前記無機粉末コーティング層の平均厚み／前記有機物質製球状物の平均直径≧０．１の関係を満たす請求項７または請求項８に記載の無機多孔質焼結体の製造方法。 The average thickness of the inorganic powder coating layer and the average diameter of the organic material spheres are:
The manufacturing method of the inorganic porous sintered compact of Claim 7 or Claim 8 satisfy | filling the relationship of the average thickness of the said inorganic powder coating layer / the average diameter of the said organic substance spherical material> 0.1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016211657A JP6890239B2 (en) | 2016-10-28 | 2016-10-28 | Method for manufacturing inorganic porous sintered body and inorganic porous sintered body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016211657A JP6890239B2 (en) | 2016-10-28 | 2016-10-28 | Method for manufacturing inorganic porous sintered body and inorganic porous sintered body |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2020198711A Division JP2021050134A (en) | 2020-11-30 | 2020-11-30 | Porous inorganic sintered body and method of producing porous inorganic sintered body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2018070409A true JP2018070409A (en) | 2018-05-10 |
| JP6890239B2 JP6890239B2 (en) | 2021-06-18 |
Family
ID=62113755
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2016211657A Active JP6890239B2 (en) | 2016-10-28 | 2016-10-28 | Method for manufacturing inorganic porous sintered body and inorganic porous sintered body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6890239B2 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05163082A (en) * | 1991-12-16 | 1993-06-29 | Tokin Corp | Production of porous sintered compact |
| JPH0959077A (en) * | 1995-08-21 | 1997-03-04 | Riboole:Kk | Expanded ceramic formed plate |
| JP2005154156A (en) * | 2003-11-20 | 2005-06-16 | Honda Motor Co Ltd | Manufacturing method of ceramic molded product with three-dimensional network structure |
| JP2007217254A (en) * | 2006-02-20 | 2007-08-30 | Hiroshima Industrial Promotion Organization | Porous calcium phosphate based ceramic and method of manufacturing the same |
-
2016
- 2016-10-28 JP JP2016211657A patent/JP6890239B2/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05163082A (en) * | 1991-12-16 | 1993-06-29 | Tokin Corp | Production of porous sintered compact |
| JPH0959077A (en) * | 1995-08-21 | 1997-03-04 | Riboole:Kk | Expanded ceramic formed plate |
| JP2005154156A (en) * | 2003-11-20 | 2005-06-16 | Honda Motor Co Ltd | Manufacturing method of ceramic molded product with three-dimensional network structure |
| JP2007217254A (en) * | 2006-02-20 | 2007-08-30 | Hiroshima Industrial Promotion Organization | Porous calcium phosphate based ceramic and method of manufacturing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6890239B2 (en) | 2021-06-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Koh et al. | Effect of polystyrene addition on freeze casting of ceramic/camphene slurry for ultra‐high porosity ceramics with aligned pore channels | |
| Kim et al. | Fabrication of open‐cell, microcellular silicon carbide ceramics by carbothermal reduction | |
| Luyten et al. | Different methods to synthesize ceramic foams | |
| US10500639B2 (en) | Additive manufacturing of articles comprising beryllium | |
| Azarniya et al. | Physicomechanical properties of porous materials by spark plasma sintering | |
| WO2012102343A1 (en) | Silicon melt contacting member and process for production thereof, and process for production of crystalline silicon | |
| US20190375688A1 (en) | Sintering control method of ceramic manufacturing | |
| CN111479791B (en) | Method for preparing aluminum nitride foam | |
| JP5429526B2 (en) | Method for producing ceramic porous body | |
| Vijayan et al. | Low‐density open cellular silicon carbide foams from sucrose and silicon powder | |
| JP2010222155A (en) | Silicon carbide sintered compact and method for producing the same | |
| JP2017039997A (en) | Aluminum alloy-ceramic composite material and production method for aluminum alloy-ceramic composite material | |
| JP4213612B2 (en) | Method for producing porous structure | |
| JP2018070409A (en) | Inorganic porous sintered compact and method for producing the same | |
| Dong et al. | Fabrication of highly porous chromium carbide with multiple pore structure | |
| JP2011501783A (en) | Metal powder mixture and use thereof | |
| JP2021050134A (en) | Porous inorganic sintered body and method of producing porous inorganic sintered body | |
| JP2017106112A (en) | Method for producing porous shaped body | |
| JP2005042193A (en) | Method for manufacturing metal- or ceramic-containing foamed sintered body | |
| JP6909639B2 (en) | Porous Silicon Carbide Composites and Silicon Carbide Heaters | |
| Reschke et al. | Polymer derived ceramic foams with additional strut porosity | |
| Ghaderi Hamidi et al. | Reduction of sintering temperature of porous tungsten skeleton used for production of W-Cu composites by ultra high compaction pressure of tungsten powder | |
| JP2007022914A (en) | Method for manufacturing silicon/silicon carbide composite material | |
| JP2004323291A (en) | Aluminum-ceramic composite and its producing method | |
| JP2016199459A (en) | Method for producing metal-ceramics composite material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20191010 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20200914 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20201013 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20201130 |
|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20201130 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20210323 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20210413 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6890239 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |