JP2006306673A - Method of manufacturing porous ceramic - Google Patents
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- JP2006306673A JP2006306673A JP2005132713A JP2005132713A JP2006306673A JP 2006306673 A JP2006306673 A JP 2006306673A JP 2005132713 A JP2005132713 A JP 2005132713A JP 2005132713 A JP2005132713 A JP 2005132713A JP 2006306673 A JP2006306673 A JP 2006306673A
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- 239000000919 ceramic Substances 0.000 title claims abstract description 66
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 65
- 239000000463 material Substances 0.000 claims abstract description 85
- 239000002245 particle Substances 0.000 claims abstract description 37
- 238000010438 heat treatment Methods 0.000 claims abstract description 30
- 230000035699 permeability Effects 0.000 claims abstract description 27
- 239000008187 granular material Substances 0.000 claims abstract description 22
- 238000010304 firing Methods 0.000 claims abstract description 15
- 239000002994 raw material Substances 0.000 claims abstract description 11
- 239000000654 additive Substances 0.000 claims abstract description 9
- 238000000465 moulding Methods 0.000 claims description 37
- 239000011148 porous material Substances 0.000 claims description 17
- 239000000843 powder Substances 0.000 claims description 16
- 239000011802 pulverized particle Substances 0.000 claims description 3
- 238000005452 bending Methods 0.000 abstract description 16
- 238000002156 mixing Methods 0.000 abstract description 5
- 238000002360 preparation method Methods 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 59
- 238000000034 method Methods 0.000 description 38
- 230000008569 process Effects 0.000 description 19
- 238000010586 diagram Methods 0.000 description 5
- 239000000428 dust Substances 0.000 description 5
- 238000005245 sintering Methods 0.000 description 5
- 239000011230 binding agent Substances 0.000 description 4
- 238000005469 granulation Methods 0.000 description 4
- 230000003179 granulation Effects 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000007689 inspection Methods 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 238000010998 test method Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000002671 adjuvant Substances 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 238000005467 ceramic manufacturing process Methods 0.000 description 1
- 239000003610 charcoal Substances 0.000 description 1
- 238000009770 conventional sintering Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- 238000013001 point bending Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920000058 polyacrylate Polymers 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000001694 spray drying Methods 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
- Filtering Materials (AREA)
- Porous Artificial Stone Or Porous Ceramic Products (AREA)
- Press-Shaping Or Shaping Using Conveyers (AREA)
Abstract
Description
本発明は、ガスセンサのセンサ素子を覆うセンサ用フィルタ等に用いて好適な多孔質セラミックスの製造方法に関する。 The present invention relates to a method for producing porous ceramics suitable for use in a sensor filter or the like that covers a sensor element of a gas sensor.
従来、ガス漏れ等を検知するガスセンサ（特開２００２−２４３６８４号公報等参照）は知られており、通常、この種のガスセンサは、ガスの存在に反応するセンサ素子と、このセンサ素子を機械的に保護するとともにガス以外の無用な異物侵入を阻止する脱塵機能を有するセンサ用フィルタを備えている。 Conventionally, gas sensors that detect gas leaks or the like (see Japanese Patent Application Laid-Open No. 2002-243684, etc.) are known. Usually, this type of gas sensor includes a sensor element that reacts to the presence of gas, and a mechanical sensor element. And a sensor filter having a dust removing function that prevents unnecessary foreign substances other than gas from entering.
この場合、センサ用フィルタは、所要のガス透過率、例えば５０〔％〕以上のガス透過率の確保が要求されるとともに、所要の脱塵機能が要求される。したがって、通常、この種のセンサ用フィルタには、ガス透過率及び脱塵機能の双方の要請に応えることができる多孔質セラミックスが使用されており、上記公報にも、ガス検知能を有し、１３００℃までの高温下で構造が安定でかつ電極を取付けることにより高温脱塵とガス検知を同時に機能させるようにしたバルク状の多孔質セラミックスが開示されている。
ところで、このようなセンサ用フィルタに使用する多孔質セラミックスの製造方法としては、一般に、造孔剤材料を利用する造孔剤法及び造粒体材料を利用する焼結法が知られている。 By the way, generally as a manufacturing method of porous ceramics used for such a filter for sensors, a pore making method using a pore forming material and a sintering method using a granulated material are known.
この場合、前者の造孔剤法は、セラミックス粉末原料に水或いは結合剤（バインダ）を加え、スラリーとして賦形し、これを乾燥した後に焼成するセラミックスの一般成形法を基本として、ポリウレタン等によるスポンジ（造孔剤）にスラリーを染み込ませたり或いはスラリーに有機高分子や木炭等のセラミックスよりも融点の低い物質（造孔剤）を混入する方法であり、これにより、焼成時に有機物質等が燃焼し、多孔質セラミックスが得られる。 In this case, the former pore former method is based on a general ceramic molding method in which water or a binder (binder) is added to a ceramic powder raw material, shaped as a slurry, dried, and then fired. This is a method of impregnating slurry in a sponge (pore-forming agent) or mixing a substance (pore-forming agent) having a melting point lower than that of ceramics such as organic polymer and charcoal into the slurry. Burns to obtain porous ceramics.
一方、後者の焼結法は、ガラス質以外のセラミックスが多結晶体であり、素材の粒子を加熱すると物質の融点以下で粒子が変形し、粒子同士が接触面を形成する性質を利用したものである。この場合、粒子同士の接触面は粒界と呼ばれ、その周囲に気孔が形成されるとともに、焼結により、この粒成長と組織の緻密化が一緒に発生する。したがって、適度な粒径を有する粒子を焼成すれば、気孔を含む焼成体、即ち、多孔質セラミックスが得られる。 On the other hand, the latter sintering method utilizes the property that ceramics other than glass are polycrystalline, and when particles of the material are heated, the particles are deformed below the melting point of the substance and the particles form contact surfaces. It is. In this case, the contact surface between the particles is called a grain boundary, pores are formed around the boundary, and the grain growth and the densification of the structure occur together by sintering. Therefore, if particles having an appropriate particle size are fired, a fired body containing pores, that is, a porous ceramic can be obtained.
しかし、上述した造孔剤法の場合、十分なガス透過率を確保するには、造孔剤の配合比率を高くする必要があるため、反面、機械的強度（特に曲げ強さ）の低下を招いてしまう。したがって、機械的強度の要求されるセンサ用フィルタには適用できない。一方、焼結法の場合、所要の機械的強度は確保できるものの、反面、連続した気孔を十分に形成できないため、必要なガス透過率を確保できない。結局、多孔質セラミックスに係わる従来の製造方法では一長一短があり、センサ用フィルタに最適な多孔質セラミックス、即ち、ガス透過率及び機械的強度（曲げ強さ）の双方を十分に満足し得る多孔質セラミックスを得ることができない問題があった。 However, in the case of the pore former method described above, in order to ensure sufficient gas permeability, it is necessary to increase the blending ratio of the pore former, so on the other hand, the mechanical strength (particularly bending strength) is reduced. I will invite you. Therefore, it cannot be applied to a sensor filter that requires mechanical strength. On the other hand, in the case of the sintering method, although the required mechanical strength can be ensured, on the other hand, since the continuous pores cannot be formed sufficiently, the necessary gas permeability cannot be ensured. In the end, the conventional manufacturing method related to porous ceramics has advantages and disadvantages, and porous ceramics that are optimal for sensor filters, that is, porous materials that can sufficiently satisfy both gas permeability and mechanical strength (bending strength). There was a problem that ceramics could not be obtained.
本発明は、このような背景技術に存在する課題を解決した多孔質セラミックスの製造方法の提供を目的とするものである。 The object of the present invention is to provide a method for producing porous ceramics which solves the problems existing in the background art.
本発明に係る多孔質セラミックスの製造方法は、上述した課題を解決するため、所定のガス透過率を有する多孔質セラミックスＣを製造するに際し、セラミックス粉末原料と一又は二以上の添加剤を調合し、所定の粒度を有する造粒体材料Ｐｏを造粒する第一材料製造工程Ｓａと、この第一材料製造工程Ｓａで得た造粒体材料Ｐｏを所定の一次加圧力Ｆｆにより一次成形した後、所定の一次加熱温度Ｔｆにより一次焼成することにより粒子ｋ…の大きさが０．１〜１．０〔ｍｍ〕の範囲となる圧粉体材料Ｐｐを得る第二材料製造工程Ｓｂと、この第二材料製造工程Ｓｂで得た圧粉体材料Ｐｐを所定の二次加圧力Ｆｓにより二次成形した後、所定の二次加熱温度Ｔｓにより二次焼成して多孔質セラミックスＣを得る主成形工程Ｓｃを備えることを特徴とする。 In order to solve the above-described problems, the method for producing a porous ceramic according to the present invention prepares a ceramic powder raw material and one or more additives when producing a porous ceramic C having a predetermined gas permeability. After the first material manufacturing step Sa for granulating the granulated material Po having a predetermined particle size, and the granulated material Po obtained in the first material manufacturing step Sa are first molded with a predetermined primary pressure Ff A second material manufacturing step Sb for obtaining a green compact material Pp in which the size of the particles k is 0.1 to 1.0 mm by primary firing at a predetermined primary heating temperature Tf; After the green compact material Pp obtained in the second material manufacturing step Sb is secondarily molded at a predetermined secondary pressure Fs, it is secondarily fired at a predetermined secondary heating temperature Ts to obtain a porous ceramic C. Provide the process Sc And it features.
この場合、発明の好適な態様により、造粒体材料Ｐｏにおける粒子の大きさは、７０〜１３０〔μｍ〕の範囲に選定できる。一方、一次加圧力Ｆｆは、７０〜１３０〔ＭＰａ〕の範囲に選定することができるとともに、一次加熱温度Ｔｆは、９００〜１２００〔℃〕の範囲に選定することができる。また、二次加圧力Ｆｓは、８〜３０〔ＭＰａ〕の範囲に選定することができるとともに、二次加熱温度Ｔｓは、１２００〜１６００〔℃〕の範囲に選定することができる。他方、第二材料製造工程Ｓｂでは、造粒体材料Ｐｏを一次加圧力Ｆｆにより押出成形又はプレス成形することにより丸パイプ形状を有する一次成形体Ｍｆを成形し、この一次成形体Ｍｆを一次焼成して成形圧粉体Ｃａを製造するとともに、この成形圧粉体Ｃａを粉砕し、粉砕した粒子ｋ…の大きさを０．１〜１．０〔ｍｍ〕の範囲に分級して圧粉体材料Ｐｐを得ることができる。また、第二材料製造工程Ｓｂでは、他の方法として、造粒体材料Ｐｏを一次加圧力Ｆｆにより加圧成形し、粒子ｋ…の大きさが０．１〜１．０〔ｍｍ〕の範囲となる球形状の圧粉体材料Ｐｐを得ることができる。さらに、主成形工程Ｐｃでは、圧粉体材料Ｐｐを金型キャビティＡに充填することにより二次加圧力Ｆｓによりプレス成形し、所定形状を有する二次成形体Ｍｓを成形することができる。なお、多孔質セラミックスＣは、ガスセンサ１のセンサ素子２…を覆うセンサ用フィルタ３に用いることができる。 In this case, according to a preferred aspect of the invention, the size of the particles in the granulated material Po can be selected in the range of 70 to 130 [μm]. On the other hand, the primary pressure Ff can be selected in the range of 70 to 130 [MPa], and the primary heating temperature Tf can be selected in the range of 900 to 1200 [° C]. The secondary pressure Fs can be selected in the range of 8 to 30 [MPa], and the secondary heating temperature Ts can be selected in the range of 1200 to 1600 [° C]. On the other hand, in the second material manufacturing step Sb, the granulated material Po is extruded or press-molded with a primary pressure Ff to form a primary molded body Mf having a round pipe shape, and the primary molded body Mf is subjected to primary firing. Then, the green compact Ca is manufactured, and the green compact Ca is pulverized, and the size of the pulverized particles k is classified into a range of 0.1 to 1.0 [mm]. The material Pp can be obtained. Moreover, in 2nd material manufacturing process Sb, as another method, the granulated material Po is pressure-molded by the primary applied pressure Ff, and the magnitude | size of the particle k ... is the range of 0.1-1.0 [mm]. A spherical green compact material Pp can be obtained. Further, in the main molding step Pc, the green compact material Pp is filled in the mold cavity A and press-molded by the secondary pressurizing force Fs, whereby the secondary molded body Ms having a predetermined shape can be molded. The porous ceramics C can be used for the sensor filter 3 that covers the sensor elements 2 of the gas sensor 1.
このような手法による本発明に係る多孔質セラミックスの製造方法によれば、次のような顕著な効果を奏する。 According to the method for producing the porous ceramics according to the present invention by such a technique, the following remarkable effects can be obtained.
（１） 粒子ｋ…の大きさが０．１〜１．０〔ｍｍ〕の範囲となる圧粉体材料Ｐｐを利用して多孔質セラミックスＣを製造するようにしたため、ガスセンサ１のセンサ用フィルタ３等における所要のガス透過率及び所要の機械的強度（曲げ強さ）の双方を十分に確保することができる。 (1) Since the porous ceramics C is manufactured by using the green compact material Pp in which the size of the particles k is in the range of 0.1 to 1.0 [mm], the sensor filter of the gas sensor 1 Both the required gas permeability and the required mechanical strength (bending strength) at 3 etc. can be sufficiently ensured.
（２） 好適な態様により、造粒体材料Ｐｏにおける粒子の大きさを、６０〜１２０〔μｍ〕の範囲に選定し、また、一次加圧力Ｆｆを、７０〜１３０〔ＭＰａ〕に選定するとともに、一次加熱温度Ｔｆを、９００〜１２００〔℃〕に選定し、さらに、二次加圧力Ｆｓを、８〜３０〔ＭＰａ〕に選定するとともに、二次加熱温度Ｔｓを、１２００〜１６００〔℃〕に選定すれば、（１）の効果を十分に引出すことができる最適な多孔質セラミックスＣを得ることができる。 (2) According to a preferred embodiment, the particle size in the granulated material Po is selected in the range of 60 to 120 [μm], and the primary pressure Ff is selected in the range of 70 to 130 [MPa]. The primary heating temperature Tf is selected from 900 to 1200 [° C.], the secondary pressure Fs is selected from 8 to 30 [MPa], and the secondary heating temperature Ts is set from 1200 to 1600 [° C.]. If selected, an optimum porous ceramic C that can sufficiently bring out the effect of (1) can be obtained.
（３） 好適な態様により、第二材料製造工程Ｓｂにおいて、造粒体材料Ｐｏを一次加圧力Ｆｆにより押出成形又はプレス成形することにより丸パイプ形状を有する一次成形体Ｍｆを成形し、この一次成形体Ｍｆを一次焼成して成形圧粉体Ｃａを製造するとともに、この成形圧粉体Ｃａを粉砕し、粉砕した粒子ｋ…の大きさを０．１〜１．０〔ｍｍ〕の範囲に分級して圧粉体材料Ｐｐを得るようにすれば、一次成形体Ｍｆを平面形状に成形する場合に比べ、成形時における接触面の面積を小さくでき、よりガス透過率を高めることができる。 (3) According to a preferred embodiment, in the second material manufacturing step Sb, the primary molded body Mf having a round pipe shape is formed by extruding or press-molding the granulated body material Po with the primary pressure Ff. The green compact Mf is primarily fired to produce a green compact Ca. The green compact Ca is pulverized and the size of the pulverized particles k is in the range of 0.1 to 1.0 [mm]. If the green compact material Pp is obtained by classification, the area of the contact surface at the time of molding can be reduced and the gas permeability can be further increased as compared with the case where the primary molded body Mf is molded into a planar shape.
（４） 好適な態様により、第二材料製造工程Ｓｂにおいて、造粒体材料Ｐｏを一次加圧力Ｆｆにより加圧成形し、粒子ｋ…の大きさが０．１〜１．０〔ｍｍ〕の範囲となる球形状の圧粉体材料Ｐｐを得るようにすれば、より単純化した造粒工程を経て圧粉体材料Ｐｐを得れるとともに、圧粉体材料Ｐｐの均質性を確保することができる。 (4) According to a preferred embodiment, in the second material manufacturing step Sb, the granulated material Po is pressure-molded by the primary pressure Ff, and the size of the particles k is 0.1 to 1.0 [mm]. If the spherical green compact material Pp in the range is obtained, the green compact material Pp can be obtained through a more simplified granulation process, and the homogeneity of the green compact material Pp can be ensured. it can.
（５） 好適な態様により、主成形工程Ｐｃにおいて、圧粉体材料Ｐｐを金型キャビティＡに充填することにより二次加圧力Ｆｓによりプレス成形し、所定形状を有する二次成形体Ｍｓを成形するようにすれば、成形条件を設定した一般的なセラミックス成形法をそのまま利用でき、製造コストの低減及び量産性の向上に寄与できる。 (5) According to a preferred embodiment, in the main molding step Pc, the green compact material Pp is filled into the mold cavity A and press-molded by the secondary pressure Fs to form a secondary molded body Ms having a predetermined shape. By doing so, a general ceramic forming method in which the forming conditions are set can be used as it is, which can contribute to a reduction in manufacturing cost and an improvement in mass productivity.
（６） 好適な態様により、多孔質セラミックスＣとして、ガスセンサ１のセンサ素子２…を覆うセンサ用フィルタ３に用いれば、この種のガスセンサ１におけるセンサ用フィルタ３に最適な多孔質セラミックスＣを得ることができる。 (6) According to a preferred embodiment, when the porous ceramic C is used for the sensor filter 3 that covers the sensor elements 2 of the gas sensor 1, the optimum porous ceramic C for the sensor filter 3 in this type of gas sensor 1 is obtained. be able to.
次に、本発明に係る最良の実施形態を挙げ、図面に基づき詳細に説明する。 Next, the best embodiment according to the present invention will be given and described in detail with reference to the drawings.
図１は、本実施形態に係る多孔質セラミックスＣの製造方法を順を追って示す工程図である。以下、同工程図に従って順次説明する。 FIG. 1 is a process diagram illustrating the manufacturing method of the porous ceramics C according to the present embodiment in order. Hereinafter, it demonstrates sequentially according to the process drawing.
最初に、第一材料製造工程Ｓａにより造粒体材料Ｐｏの造粒を行う。第一材料製造工程Ｓａでは、まず、調合工程によりセラミックス粉末原料と所要の添加剤を調合する（ステップＳ１）。この場合、セラミックス粉末原料には、粉末粒径が概ね０．３〔μｍ〕程度のアルミナ粉末（ＡＬ2Ｏ3）を用いる。また、添加剤には、助剤，バインダ及び純水を適量用いる。なお、助剤には、ポリアクリル酸塩等を利用できるとともに、バインダには、アクリル，ＰＶＡ（ポリビニルアルコール），ＰＥＯ（ポリエチレンオキサイド）等を利用できる。 First, the granulated material Po is granulated by the first material manufacturing process Sa. In the first material manufacturing process Sa, first, a ceramic powder raw material and required additives are prepared by a preparation process (step S1). In this case, alumina powder (AL 2 O 3 ) having a powder particle size of about 0.3 [μm] is used as the ceramic powder raw material. As additives, an appropriate amount of an auxiliary agent, a binder, and pure water is used. In addition, a polyacrylate etc. can be utilized for an adjuvant, and an acrylic, PVA (polyvinyl alcohol), PEO (polyethylene oxide), etc. can be utilized for a binder.
セラミックス粉末原料と所要の添加剤を調合したなら、混合工程により全体を均一に混合する（ステップＳ２）。この場合、ボールミル装置等を使用し、所定時間にわたり機械的に撹拌することにより十分に混合する。混合工程が終了したなら造粒工程に移行する。造粒工程では、所定の粒度を有する造粒体材料Ｐｏを造粒する（ステップＳ３）。具体的には、噴霧乾燥装置（スプレードドライヤ装置）等を使用し、造粒体材料Ｐｏにおける粒子（顆粒）の平均径が６０〜１２０〔μｍ〕の範囲、望ましくは８０〔μｍ〕程度となるように製造する。以上が第一材料製造工程Ｓａとなる。 When the ceramic powder raw material and the required additives are prepared, the whole is uniformly mixed by the mixing process (step S2). In this case, a ball mill apparatus or the like is used, and the mixture is sufficiently mixed by mechanical stirring for a predetermined time. When the mixing process is completed, the process proceeds to the granulation process. In the granulation step, the granulated material Po having a predetermined particle size is granulated (step S3). Specifically, using a spray drying device (spray dryer device) or the like, the average diameter of particles (granules) in the granulated material Po is in the range of 60 to 120 [μm], preferably about 80 [μm]. To be manufactured. The above is the first material manufacturing process Sa.
次いで、第二材料製造工程Ｓｂに移行する。第二材料製造工程Ｓｂでは、まず、一次成形工程により、第一材料製造工程Ｓａで得た造粒体材料Ｐｏを所定の一次加圧力Ｆｆにより加圧して一次成形を行う（ステップＳ４）。図２は、一次成形に用いる一次成形機１０を示す。一次成形では、一次成形機１０のシリンダ１１に、第一材料製造工程Ｓａで得た造粒体材料Ｐｏを収容し、ラム１２を一次加圧力Ｆｆにより加圧して押出成形を行う。これにより、型盤１３から矢印Ｈｏ方向に一次成形体Ｍｆが押し出され、丸パイプ形状を有する一次成形体Ｍｆが成形される。この場合、一次加圧力Ｆｆは、７０〜１３０〔ＭＰａ〕の範囲、望ましくは１００〔ＭＰａ〕程度に選定する。一次成形体Ｍｆをこのような丸パイプ形状に成形すれば、一次成形体Ｍｆを平面形状に成形する場合に比べ、後述する二次成形時における粒子ｋ…同士の接触面の面積を小さくできるため、よりガス透過率を高めることができる。なお、一次成形として押出成形を例示したが、プレス成形により同様の形状を成形してもよい。 Next, the process proceeds to the second material manufacturing process Sb. In the second material manufacturing process Sb, first, in the primary molding process, the granulated material Po obtained in the first material manufacturing process Sa is pressurized with a predetermined primary pressure Ff to perform primary molding (step S4). FIG. 2 shows a primary molding machine 10 used for primary molding. In the primary molding, the granulated material Po obtained in the first material manufacturing process Sa is accommodated in the cylinder 11 of the primary molding machine 10, and the ram 12 is pressurized by the primary pressure Ff to perform extrusion molding. As a result, the primary molded body Mf is extruded from the mold plate 13 in the direction of the arrow Ho, and the primary molded body Mf having a round pipe shape is molded. In this case, the primary pressure Ff is selected in the range of 70 to 130 [MPa], preferably about 100 [MPa]. If the primary molded body Mf is formed into such a round pipe shape, the area of the contact surface between particles k at the time of secondary molding described later can be reduced compared to the case where the primary molded body Mf is molded into a planar shape. , Gas permeability can be further increased. In addition, although extrusion molding was illustrated as primary molding, you may shape | mold the same shape by press molding.
そして、一次成形体Ｍｆが得られたなら、一次焼成工程により、当該一次成形体Ｍｆを所定の一次加熱温度Ｔｆにより一次焼成（仮焼成）して成形圧粉体Ｃａを得る（ステップＳ５）。この場合、一次加熱温度Ｔｆは、９００〜１２００〔℃〕の範囲、望ましくは１０００〜１１００〔℃〕程度に選定する。この成形圧粉体Ｃａを図４に示す。同図において、Ｄｏは成形圧粉体Ｃａの外径を示すとともに、Ｄｉは同内径を示し、本実施形態では、Ｄｏを１．９〔ｍｍ〕、Ｄｉを１．３〔ｍｍ〕になるように選定した。なお、一次焼成は、後述する二次成形時における圧粉体材料Ｐｐの潰れを防止するために行うものであり、一次焼成を行わない場合には、二次成形時の二次加圧力Ｆｓを十分に高くすることができなくなり、良好な二次成形を行うことができない。 When the primary molded body Mf is obtained, the primary molded body Mf is subjected to primary firing (preliminary firing) at a predetermined primary heating temperature Tf in the primary firing step to obtain a molded green compact Ca (step S5). In this case, the primary heating temperature Tf is selected in the range of 900 to 1200 [° C.], preferably about 1000 to 1100 [° C.]. This molded green compact Ca is shown in FIG. In the drawing, Do indicates the outer diameter of the green compact Ca and Di indicates the same inner diameter. In this embodiment, Do is 1.9 [mm] and Di is 1.3 [mm]. Selected. The primary firing is performed in order to prevent crushing of the green compact material Pp at the time of secondary molding described later. When the primary firing is not performed, the secondary pressure Fs at the time of secondary molding is set to It cannot be made sufficiently high and good secondary molding cannot be performed.
一次焼成工程により成形圧粉体Ｃａが得られたなら、粉砕工程により成形圧粉体Ｃａを粉砕する（ステップＳ６）。また、粉砕したなら分級工程により、得られた粒子ｋ…の大きさを０．１〜１．０〔ｍｍ〕の範囲、望ましくは０．３５〜０．７０〔ｍｍ〕の範囲に分級する（ステップＳ７）。分級は、後述する金型キャビティＡへの充填を可能にするためであり、充填可能なサイズを取り出すとともに、微粉末は除去することにより、製造した多孔質セラミックスＣにおける気孔Ｒ…（図１０参照）の閉塞を回避する。これにより、図５に示す圧粉体材料Ｐｐを得る。この圧粉体材料Ｐｐは、丸パイプ形状を有する成形圧粉体Ｃａを粉砕して得るため、圧粉体材料Ｐｐにおける粒子ｋ…同士の接触面積が小さくなり、実質的な気孔Ｒ…の開口面積を大きくすることができる。図６に、実際に得られた圧粉体材料Ｐｐの写真を示す。以上が第二材料製造工程Ｓｂとなる。 If the green compact Ca is obtained by the primary firing process, the green compact Ca is pulverized by the pulverization process (step S6). Moreover, if it grind | pulverizes, according to a classification process, the magnitude | size of the obtained particle k ... will be classified into the range of 0.1-1.0 [mm], desirably 0.35-0.70 [mm] ( Step S7). Classification is to enable filling into the mold cavity A, which will be described later, and the pore R in the manufactured porous ceramics C is removed by taking out the fillable size and removing the fine powder (see FIG. 10). ) To prevent blockage. Thereby, the green compact material Pp shown in FIG. 5 is obtained. Since the green compact material Pp is obtained by pulverizing a molded green compact Ca having a round pipe shape, the contact area between the particles k in the green compact material Pp becomes small, and the substantial opening of the pores R ... The area can be increased. FIG. 6 shows a photograph of the green compact material Pp actually obtained. The above is the second material manufacturing process Sb.
なお、上述した第二材料製造工程Ｓｂでは、圧粉体材料Ｐｐとしてランダム形状となる粒子ｋ…を有する圧粉体材料Ｐｐを用いたが、粒子ｋ…の形状は、必ずしもランダム形状であることを要せず、図７に示すような形の揃った球形状の圧粉体材料Ｐｐを用いてもよい。図７に示すような形の揃った球形状の圧粉体材料Ｐｐは、造粒体材料Ｐｏを所定の一次加圧力Ｆｆ、即ち、７０〜１３０〔ＭＰａ〕の範囲、望ましくは１００〔ＭＰａ〕程度に選定した一次加圧力Ｆｆにより一次成形する際に、直径０．５〔ｍｍ〕，軸方向長さ０．５〔ｍｍ〕の円柱体を加圧成形し、バレル加工（バレル研磨）を行うことにより、角の取れた球形状（球径０．５〔ｍｍ〕）の圧粉体材料Ｐｐを得ることができる。このような球形状の圧粉体材料Ｐｐを用いれば、より単純化した造粒工程を経て圧粉体材料Ｐｐを得れるとともに、圧粉体材料Ｐｐの均質性を確保することができる。 In the second material manufacturing step Sb described above, the green compact material Pp having the particles k ... having a random shape is used as the green compact material Pp. However, the shape of the particles k ... is not necessarily random. May be used, and a spherical green compact material Pp having a uniform shape as shown in FIG. 7 may be used. The spherical green compact material Pp having a uniform shape as shown in FIG. 7 has a predetermined primary pressure Ff, that is, a range of 70 to 130 [MPa], preferably 100 [MPa]. When primary molding is performed with a primary pressure Ff selected to a certain extent, a cylindrical body having a diameter of 0.5 [mm] and an axial length of 0.5 [mm] is pressure-molded and subjected to barrel processing (barrel polishing). Thus, a green compact material Pp having a rounded spherical shape (spherical diameter 0.5 [mm]) can be obtained. When such a spherical green compact material Pp is used, the green compact material Pp can be obtained through a more simplified granulation process, and the homogeneity of the green compact material Pp can be ensured.
他方、第二材料製造工程Ｓｂが終了したなら主成形工程Ｓｃに移行する。主成形工程Ｓｃでは、まず、二次成形工程により、第二材料製造工程Ｓｂで得た圧粉体材料Ｐｐを所定の二次加圧力Ｆｓにより加圧して二次成形を行う（ステップＳ８）。図３は、二次成形に用いる二次成形機２０を示す。二次成形では、二次成形機２０の金型キャビティＡに圧粉体材料Ｐｐを充填するとともに、可動型２１を二次加圧力Ｆｓにより加圧してプレス成形を行う。これにより、所要の形状を有する二次成形体Ｍｓが得られる。この場合、二次加圧力Ｆｓは、８〜３０〔ＭＰａ〕の範囲に選定する。このような主成形工程Ｓｃを用いれば、成形条件を設定した一般的なセラミックス成形法をそのまま利用できるため、製造コストの低減及び量産性の向上に寄与できる。 On the other hand, if the second material manufacturing process Sb is completed, the process proceeds to the main molding process Sc. In the main molding step Sc, first, in the secondary molding step, the green compact material Pp obtained in the second material manufacturing step Sb is pressurized with a predetermined secondary pressure Fs to perform secondary molding (step S8). FIG. 3 shows a secondary molding machine 20 used for secondary molding. In the secondary molding, the mold cavity A of the secondary molding machine 20 is filled with the green compact material Pp, and the movable mold 21 is pressed by the secondary pressure Fs to perform press molding. Thereby, the secondary molded object Ms which has a required shape is obtained. In this case, the secondary pressure Fs is selected in the range of 8 to 30 [MPa]. If such a main forming step Sc is used, a general ceramic forming method in which forming conditions are set can be used as it is, which can contribute to a reduction in manufacturing cost and an improvement in mass productivity.
そして、二次成形体Ｍｓが得られたなら、二次焼成工程により、当該二次成形体Ｍｓを所定の二次加熱温度Ｔｓにより二次焼成（本焼成）して多孔質セラミックスＣ、具体的には、図９に示すガスセンサ１のセンサ素子２…を覆うセンサ用フィルタ３を得る（ステップＳ９）。このセンサ用フィルタ３を図８に示す。この場合、二次加熱温度Ｔｓは、１２００〜１６００〔℃〕の範囲に選定する。二次加熱温度Ｔｓは、使用するセラミックス粉末原料に対応した温度を適宜設定することができる。センサ用フィルタ３が得られたなら、検査工程により必要な検査を行う（ステップＳ１０）。検査項目としては、センサ用フィルタ３の外径寸法，厚み寸法，高さ寸法，ガス透過率，外観等が適用される。 Then, when the secondary molded body Ms is obtained, the secondary molded body Ms is subjected to secondary firing (main firing) at a predetermined secondary heating temperature Ts in the secondary firing step. The sensor filter 3 that covers the sensor elements 2 of the gas sensor 1 shown in FIG. 9 is obtained (step S9). This sensor filter 3 is shown in FIG. In this case, the secondary heating temperature Ts is selected in the range of 1200 to 1600 [° C.]. The secondary heating temperature Ts can be appropriately set to a temperature corresponding to the ceramic powder raw material to be used. If the sensor filter 3 is obtained, the necessary inspection is performed by the inspection process (step S10). As inspection items, the outer diameter, thickness, height, gas permeability, appearance, and the like of the sensor filter 3 are applied.
なお、ガスセンサ１は、図９に示すように、ベース５の上下面に四本のリード６…が貫通し、ベース５の上面側に位置するリード６…にセンサ素子２，２を接続する。一方、センサ用フィルタ３は、図８に示すように、円筒部３ｆとこの円筒部３ｆの上端を閉塞する天面部３ｕによりカップ状に形成するため、このセンサ用フィルタ３をベース５に装着してセンサ素子２…を覆う。図９に例示するガスセンサ１の大きさは、直径１２〔ｍｍ〕，高さ１０〔ｍｍ〕（リード６…を除く）である。 In the gas sensor 1, as shown in FIG. 9, four leads 6 penetrate through the upper and lower surfaces of the base 5, and the sensor elements 2 are connected to the leads 6 positioned on the upper surface side of the base 5. On the other hand, as shown in FIG. 8, the sensor filter 3 is formed in a cup shape by a cylindrical portion 3f and a top surface portion 3u that closes the upper end of the cylindrical portion 3f. Cover the sensor elements 2. The size of the gas sensor 1 illustrated in FIG. 9 is 12 [mm] in diameter and 10 [mm] in height (excluding the leads 6...).
これにより、センサ素子２…に対しては機械的な保護が図られる。また、センサ用フィルタ３（多孔質セラミックスＣ）の内部構造は、図１０に示すように、圧粉体材料Ｐｐの粒子ｋ…同士の結合により成立しており、粒界となる接触面の周囲における空間により気孔Ｒ…が形成される。したがって、この気孔Ｒ…に沿ったガス通路が確保され、ガスの透過が許容されるとともに、ガス以外の無用な異物侵入が阻止される脱塵機能が確保される。図１０にガス通路を点線矢印Ｈｓ…で示す。 Thereby, mechanical protection is achieved for the sensor elements 2. Further, as shown in FIG. 10, the internal structure of the sensor filter 3 (porous ceramic C) is formed by the combination of the particles k... Of the green compact material Pp, and around the contact surface that becomes the grain boundary. The pores R are formed by the space at. Therefore, a gas passage along the pores R is secured, and the permeation of gas is allowed, and a dust removing function that prevents intrusion of unnecessary foreign substances other than gas is secured. FIG. 10 shows the gas passage by dotted arrows Hs.
次に、図１１及び図１２を参照し、本実施形態に係る製造方法により製造した多孔質セラミックスＣの特性について説明する。 Next, with reference to FIG.11 and FIG.12, the characteristic of the porous ceramics C manufactured with the manufacturing method which concerns on this embodiment is demonstrated.
図１２に、各実施例（及び従来例）により製造した多孔質セラミックスＣの特性データ（実験結果）を示す。同特性データにおいて、ガス透過率は、図１１に示す測定装置３０により測定するとともに、曲げ強さは、「ＪＩＳ−Ｒ１６０１」によるファインセラミックスの曲げ強さ試験方法により測定した。なお、以下の説明においては、特に数値を挙げた条件を除き、他の数値的条件は上述した実施形態に準じている。 FIG. 12 shows characteristic data (experimental results) of porous ceramics C manufactured according to each example (and the conventional example). In the same characteristic data, the gas permeability was measured by the measuring device 30 shown in FIG. 11, and the bending strength was measured by a bending strength test method for fine ceramics according to “JIS-R1601”. In the following description, other numerical conditions are the same as those in the above-described embodiment, except for the conditions in which numerical values are given.
図１１に示す測定装置３０は、多孔質セラミックスＣによる試料片Ｃｔを挟んだ状態で密閉する一対の試料ホルダ３１ａ，３１ｂを備え、一方の試料ホルダ３１ａに試料片Ｃｔの一方の面に臨むガス供給管３２ｕを接続するとともに、他方の試料ホルダ３１ｂに試料片Ｃｔの他方の面に臨むガス排出管３２ｄを接続する。そして、ガス供給管３２ｕの始端に窒素ボンベ３３を接続し、さらに、ガス供給管３２ｕの中途に、減圧器（レギュレータ）３４及びバルブ３５を接続するとともに、ガス排出管３２ｄの終端にデジタル流量計３６を接続した構成を有する。これにより、ガス透過率を測定する際は、試料片Ｃｔをセットしない空状態で減圧器３４とバルブ３５を調整し、ガス流量を９〔リットル／ｍｉｎ〕（＝Ｑａ）に、また、ガス圧を０．０３〔ＭＰａ〕にそれぞれ設定するとともに、この後、図１１に示すように、試料片Ｃｔを一対の試料ホルダ３１ａ，３１ｂの間にセットし、流量計３６により流量Ｑｂを計測すれば、（Ｑｂ／Ｑａ）×１００によりガス透過率〔％〕を求めることができる。 A measuring apparatus 30 shown in FIG. 11 includes a pair of sample holders 31a and 31b that are sealed in a state in which a sample piece Ct made of porous ceramics C is sandwiched, and gas that faces one surface of the sample piece Ct in one sample holder 31a. The supply pipe 32u is connected, and the gas discharge pipe 32d facing the other surface of the sample piece Ct is connected to the other sample holder 31b. A nitrogen cylinder 33 is connected to the start end of the gas supply pipe 32u, and a decompressor (regulator) 34 and a valve 35 are connected to the middle of the gas supply pipe 32u, and a digital flow meter is connected to the end of the gas discharge pipe 32d. 36 is connected. Thereby, when measuring the gas permeability, the decompressor 34 and the valve 35 are adjusted in an empty state where the sample piece Ct is not set, the gas flow rate is set to 9 [liter / min] (= Qa), and the gas pressure Is set to 0.03 [MPa], and thereafter, as shown in FIG. 11, the sample piece Ct is set between the pair of sample holders 31a and 31b, and the flow rate Qb is measured by the flow meter 36. , (Qb / Qa) × 100, the gas permeability [%] can be obtained.
また、「ＪＩＳ−Ｒ１６０１」による曲げ強さ試験方法は、三点曲げ試験方法であり、試料片Ｃｔを一定距離に配置した二支点上に置き、支点間の中央の一点に荷重を加える。これにより、試料片Ｃｔが折れた時の最大曲げ応力を曲げ強さ〔ＭＰａ〕として測定することができる。 The bending strength test method according to “JIS-R1601” is a three-point bending test method, in which the sample piece Ct is placed on two fulcrums arranged at a fixed distance, and a load is applied to one central point between the fulcrums. Thereby, the maximum bending stress when the sample piece Ct is bent can be measured as the bending strength [MPa].
図１２に示す特性データにおいて、実施例１〜５は、図５に示すランダム形状の圧粉体材料Ｐｐであって、粒子ｋ…の大きさを０．３〜０．５〔ｍｍ〕の範囲に分級した圧粉体材料Ｐｐを使用するとともに、異なる一次加熱温度Ｔｆを設定した場合の特性データである。この場合、実施例１は「加熱なし」，実施例２は「９００〔℃〕」，実施例３は「１０００〔℃〕」，実施例４は「１１００〔℃〕」，実施例５は「１２００〔℃〕」にそれぞれ設定した。 In the characteristic data shown in FIG. 12, Examples 1-5 are the green compact material Pp of the random shape shown in FIG. 5, Comprising: The magnitude | size of particle | grain k ... is 0.3-0.5 [mm]. FIG. 5 is characteristic data when the green compact material Pp classified into 2 is used and a different primary heating temperature Tf is set. In this case, Example 1 is “no heating”, Example 2 is “900 [° C.]”, Example 3 is “1000 [° C.]”, Example 4 is “1100 [° C.]”, and Example 5 is “ 1200 [° C.] ”.
実施例１〜５による特性データから、ガス透過率に対し、例えば、５０〔％〕以上を狙い値として判定した場合、一次加熱温度Ｔｆが低い領域、即ち、「加熱なし」と「９００〔℃〕」ではガス透過率が狙い値に届いていない。他方、一次加熱温度Ｔｆが高い領域、即ち、「１２００〔℃〕」の場合には成形不良を生じる。よって、実施例１〜５による特性データから、一次加熱温度Ｔｆとしては、前述した９００〜１２００〔℃〕の範囲、望ましくは１０００〜１１００〔℃〕の範囲に選定することが好適である。また、曲げ強さに対し、例えば、３０〔ＭＰａ〕以上を狙い値として判定した場合、実施例１〜５のいずれの特性データも狙い値を満足している。なお、実施例１〜５による特性データから明らかなように、一次加熱温度Ｔｆが高くなれば、ガス透過率が高くなり、かつ曲げ強さが低くなる相関関係を有している。 From the characteristic data according to Examples 1 to 5, when it is determined that the gas permeability is 50% or more, for example, the primary heating temperature Tf is low, that is, “no heating” and “900 [° C. ] ”, The gas permeability has not reached the target value. On the other hand, in the region where the primary heating temperature Tf is high, that is, “1200 [° C.]”, a molding defect occurs. Therefore, from the characteristic data according to Examples 1 to 5, it is preferable to select the primary heating temperature Tf in the above-described range of 900 to 1200 [° C.], preferably in the range of 1000 to 1100 [° C.]. For example, when the bending strength is determined to be 30 [MPa] or more as the target value, any of the characteristic data of Examples 1 to 5 satisfies the target value. As is clear from the characteristic data of Examples 1 to 5, there is a correlation in which the gas permeability increases and the bending strength decreases as the primary heating temperature Tf increases.
一方、実施例６〜８は、図５に示すランダム形状の圧粉体材料Ｐｐであって、一次加熱温度Ｔｆを「１１００〔℃〕」に設定するとともに、圧粉体材料Ｐｐの粒子ｋ…を異なる大きさに設定した場合の特性データである。この場合、実施例６は「０．１〜０．３〔ｍｍ〕」，実施例７は「０．５〜０．７〔ｍｍ〕」，実施例８は「０．７〜１．０〔ｍｍ〕」にそれぞれ設定した。 On the other hand, Examples 6 to 8 are green compact materials Pp having a random shape shown in FIG. 5, and the primary heating temperature Tf is set to “1100 [° C.]” and the particles k of the green compact materials Pp. Is characteristic data when is set to a different size. In this case, Example 6 is “0.1 to 0.3 [mm]”, Example 7 is “0.5 to 0.7 [mm]”, and Example 8 is “0.7 to 1.0 [mm]”. mm] ”.
実施例６〜８による特性データから、ガス透過率に対し、例えば、５０〔％〕以上を狙い値として判定した場合、実施例６〜８のいずれの特性データも狙い値を満足している。また、曲げ強さに対し、例えば、３０〔ＭＰａ〕以上を狙い値として判定した場合、「０．７〜１．０〔ｍｍ〕」は狙い値に届いていない。よって、実施例６〜８から、圧粉体材料Ｐｐにおける粒子ｋ…の大きさは、０．１〜１．０〔ｍｍ〕の範囲、望ましくは、０．３〜０．７〔ｍｍ〕の範囲に選定することが好適である。なお、実施例６〜８による特性データから明らかなように、圧粉体材料Ｐｐにおける粒子ｋ…が大きくなれば、ガス透過率が高くなり、かつ曲げ強さが低くなる相関関係を有している。 From the characteristic data according to Examples 6 to 8, when it is determined that the gas permeability is 50% or more as a target value, any of the characteristic data of Examples 6 to 8 satisfies the target value. For example, when the bending strength is determined to be 30 [MPa] or more as a target value, “0.7 to 1.0 [mm]” does not reach the target value. Therefore, from Examples 6 to 8, the size of the particles k in the green compact material Pp is in the range of 0.1 to 1.0 [mm], preferably 0.3 to 0.7 [mm]. It is preferable to select the range. As is clear from the characteristic data obtained in Examples 6 to 8, there is a correlation in which the gas permeability increases and the bending strength decreases when the particle k in the green compact material Pp increases. Yes.
さらに、実施例９は、図７に示す球形状の圧粉体材料Ｐｐであって、一次加熱温度Ｔｆを「１１００〔℃〕」に設定するとともに、圧粉体材料Ｐｐにおける粒子ｋ…の大きさを、０．３〜０．５〔ｍｍ〕に設定した場合の特性データを示す。この場合、ガス透過率は５０〔％〕、曲げ強さは５０〔ＭＰａ〕を得ている。 Further, the ninth embodiment is a spherical green compact material Pp shown in FIG. 7, and the primary heating temperature Tf is set to “1100 [° C.]” and the size of the particles k... The characteristic data when the thickness is set to 0.3 to 0.5 [mm] are shown. In this case, the gas permeability is 50 [%] and the bending strength is 50 [MPa].
このように、本実施形態に係る多孔質セラミックスＣの製造方法においては、特に、第二材料製造工程Ｓｂにおける条件設定が重要となり、この条件設定が多孔質セラミックスＣの特性（特性データ）に大きく影響する。なお、主成形工程Ｓｃは、基本的に一般的なセラミックス製造工程に準じた実施が可能である。 As described above, in the method for manufacturing the porous ceramic C according to the present embodiment, the condition setting in the second material manufacturing process Sb is particularly important, and this condition setting greatly affects the characteristics (characteristic data) of the porous ceramic C. Affect. The main forming step Sc can be basically performed in accordance with a general ceramic manufacturing process.
他方、従来例１は、前述した従来の造孔剤法による特性データであり、使用した試料片の形状や大きさは、実施例１〜９の場合と同じである。また、従来例２は、前述した従来の焼結法による特性データであり、使用した試料片の形状や大きさは、実施例１〜９の場合と同じである。先に記載したように、造孔剤法（従来例１）の場合、所要のガス透過率は確保できるものの、曲げ強さは極端に小さくなることが明らかである。一方、焼結法（従来例２）の場合、所要の曲げ強さは確保できるものの、ガス透過率は極端に小さくなることが明らかである。 On the other hand, Conventional Example 1 is characteristic data obtained by the conventional pore forming method described above, and the shape and size of the used sample pieces are the same as those in Examples 1-9. Further, Conventional Example 2 is characteristic data obtained by the conventional sintering method described above, and the shape and size of the used sample pieces are the same as those in Examples 1 to 9. As described above, in the case of the pore former method (conventional example 1), it is clear that the required gas permeability can be secured, but the bending strength becomes extremely small. On the other hand, in the case of the sintering method (conventional example 2), it is clear that the required permeability is ensured, but the gas permeability is extremely small.
このように、本実施形態に係る多孔質セラミックスの製造方法によれば、粒子ｋ…の大きさが０．１〜１．０〔ｍｍ〕の範囲となる圧粉体材料Ｐｐを利用して多孔質セラミックスＣを製造するようにしたため、ガスセンサ１のセンサ用フィルタ３における所要のガス透過率及び所要の機械的強度（曲げ強さ）の双方を十分に確保できるという所望の効果を享受できる。特に、造粒体材料Ｐｏにおける粒子の大きさを、６０〜１２０〔μｍ〕の範囲に選定し、また、一次加圧力Ｆｆを、７０〜１３０〔ＭＰａ〕に選定するとともに、一次加熱温度Ｔｆを、９００〜１２００〔℃〕に選定し、さらに、二次加圧力Ｆｓを、８〜３０〔ＭＰａ〕に選定するとともに、二次加熱温度Ｔｓを、１２００〜１６００〔℃〕に選定したため、上記効果を十分に引出すことができる最適な多孔質セラミックスＣを得ることができる。 As described above, according to the method for manufacturing a porous ceramic according to the present embodiment, the porous material is porous using the green compact material Pp in which the size of the particles k is 0.1 to 1.0 [mm]. Since the quality ceramic C is manufactured, it is possible to enjoy the desired effect that both the required gas permeability and the required mechanical strength (bending strength) in the sensor filter 3 of the gas sensor 1 can be sufficiently secured. In particular, the particle size in the granulated material Po is selected in the range of 60 to 120 [μm], the primary pressure Ff is selected in the range of 70 to 130 [MPa], and the primary heating temperature Tf is set to , 900 to 1200 [° C.], the secondary pressure Fs is selected to 8 to 30 [MPa], and the secondary heating temperature Ts is selected to 1200 to 1600 [° C.] It is possible to obtain an optimal porous ceramics C that can sufficiently draw out.
以上、最良の実施形態について詳細に説明したが、本発明は、このような実施形態に限定されるものではなく、細部の構成，形状，素材，数量，数値等において、本発明の要旨を逸脱しない範囲で、任意に変更，追加，削除することができる。例えば、セラミックス粉末原料としてアルミナ粉末を例示したが、ジルコニア粉末等の一般的なセラミックス材料を含む他の各種セラミックス材料（粉末原料）を用いることができる。また、添加剤も、例示の添加剤をはじめ、調合するセラミックス粉末原料に応じた各種添加剤を用いることができる。さらに、一次成形及び二次成形も必要に応じて例示以外の各種成形法を用いることができる。 Although the best embodiment has been described in detail above, the present invention is not limited to such an embodiment, and departs from the gist of the present invention in the detailed configuration, shape, material, quantity, numerical value, and the like. It can be changed, added, or deleted as long as it is not. For example, although alumina powder is exemplified as the ceramic powder raw material, other various ceramic materials (powder raw materials) including general ceramic materials such as zirconia powder can be used. Moreover, various additives according to the ceramic powder raw material to mix | blend can be used also for an additive including the illustrated additive. Furthermore, primary molding and secondary molding can also use various molding methods other than those illustrated as necessary.
本発明に係る多孔質セラミックスの製造方法は、ガスセンサ１のセンサ素子２…を覆うセンサ用フィルタ３に用いて最適である。この場合、ガスには、水素ガス，都市ガス，ＬＰガス，排気ガス等の各種ガスを適用できる。また、フィルタ作用が要求される同様の各種用途、即ち、流体を通過するも一定の大きさ以上の異物の通過を阻止する各種フィルタ類や同種の類似部材に利用することができる。 The method for producing porous ceramics according to the present invention is optimal for use in the sensor filter 3 that covers the sensor elements 2 of the gas sensor 1. In this case, various gases such as hydrogen gas, city gas, LP gas, and exhaust gas can be applied to the gas. Further, it can be used in various similar applications requiring a filter action, that is, various filters that pass a fluid but block the passage of foreign matters of a certain size or similar members.
１ ガスセンサ
２ センサ素子
３ センサ用フィルタ
Ｃ 多孔質セラミックス
Ｃａ 成形圧粉体
Ｍｆ 一次成形体
Ｍｓ 二次成形体
Ｐｏ 造粒体材料
Ｐｐ 圧粉体材料
Ｓａ 第一材料製造工程
Ｓｂ 第二材料製造工程
Ｓｃ 主成形工程
Ａ 金型キャビティ
Ｆｆ 一次加圧力
Ｆｓ 二次加圧力
Ｔｆ 一次加熱温度
Ｔｓ 二次加熱温度
ｋ… 圧粉体材料の粒子
DESCRIPTION OF SYMBOLS 1 Gas sensor 2 Sensor element 3 Sensor filter C Porous ceramic Ca Molding green compact Mf Primary compact Ms Secondary compact Po Po Granule material Pp Compact material Sa First material manufacturing process Sb Second material manufacturing process Sc Main molding process A Mold cavity Ff Primary pressure Fs Secondary pressure Tf Primary heating temperature Ts Secondary heating temperature k ... Particles of green compact material
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2007292736A (en) * | 2006-03-27 | 2007-11-08 | Citizen Fine Tech Co Ltd | Porous cover and its manufacturing method |
| JP2011520740A (en) * | 2007-12-20 | 2011-07-21 | ザ、リージェンツ、オブ、ザ、ユニバーシティ、オブ、カリフォルニア | Sintered porous structure and manufacturing method thereof |
| JP2012517600A (en) * | 2009-02-12 | 2012-08-02 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング | Sensor element of gas sensor and method of operating the same |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6131369A (en) * | 1984-07-20 | 1986-02-13 | 三菱レイヨン株式会社 | Porous body and its manufacturing method |
| JPS62278177A (en) * | 1986-05-28 | 1987-12-03 | 東京窯業株式会社 | Manufacture of porous ceramics |
| JPS62283882A (en) * | 1986-05-29 | 1987-12-09 | 東京窯業株式会社 | Manufacture of porous ceramics |
| JPH038780A (en) * | 1989-02-22 | 1991-01-16 | Showa Denko Kk | Sintered fine particle of ceramics and production thereof |
| JPH06183858A (en) * | 1992-12-16 | 1994-07-05 | Sanshu Ceramic Kk | Production of porous sintered material |
| JPH1072270A (en) * | 1996-06-26 | 1998-03-17 | Tsukishima Kikai Co Ltd | Production of paving material excellent in water retentivity |
-
2005
- 2005-04-28 JP JP2005132713A patent/JP4713214B2/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6131369A (en) * | 1984-07-20 | 1986-02-13 | 三菱レイヨン株式会社 | Porous body and its manufacturing method |
| JPS62278177A (en) * | 1986-05-28 | 1987-12-03 | 東京窯業株式会社 | Manufacture of porous ceramics |
| JPS62283882A (en) * | 1986-05-29 | 1987-12-09 | 東京窯業株式会社 | Manufacture of porous ceramics |
| JPH038780A (en) * | 1989-02-22 | 1991-01-16 | Showa Denko Kk | Sintered fine particle of ceramics and production thereof |
| JPH06183858A (en) * | 1992-12-16 | 1994-07-05 | Sanshu Ceramic Kk | Production of porous sintered material |
| JPH1072270A (en) * | 1996-06-26 | 1998-03-17 | Tsukishima Kikai Co Ltd | Production of paving material excellent in water retentivity |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007292736A (en) * | 2006-03-27 | 2007-11-08 | Citizen Fine Tech Co Ltd | Porous cover and its manufacturing method |
| JP2011520740A (en) * | 2007-12-20 | 2011-07-21 | ザ、リージェンツ、オブ、ザ、ユニバーシティ、オブ、カリフォルニア | Sintered porous structure and manufacturing method thereof |
| JP2012517600A (en) * | 2009-02-12 | 2012-08-02 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング | Sensor element of gas sensor and method of operating the same |
| US8833141B2 (en) | 2009-02-12 | 2014-09-16 | Robert Bosch Gmbh | Sensor element of a gas sensor and method for operating the same |
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