JPH02290642A - Manufacture of ceramic core - Google Patents
Manufacture of ceramic coreInfo
- Publication number
- JPH02290642A JPH02290642A JP10897589A JP10897589A JPH02290642A JP H02290642 A JPH02290642 A JP H02290642A JP 10897589 A JP10897589 A JP 10897589A JP 10897589 A JP10897589 A JP 10897589A JP H02290642 A JPH02290642 A JP H02290642A
- Authority
- JP
- Japan
- Prior art keywords
- binder
- weight
- sinterable
- sintering
- core
- 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.)
- Pending
Links
- 239000000919 ceramic Substances 0.000 title claims abstract description 19
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 45
- 239000011230 binding agent Substances 0.000 claims abstract description 34
- 238000002156 mixing Methods 0.000 claims abstract description 22
- 239000000126 substance Substances 0.000 claims description 37
- 239000000203 mixture Substances 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 17
- 238000000859 sublimation Methods 0.000 claims description 5
- 230000008022 sublimation Effects 0.000 claims description 5
- 238000002347 injection Methods 0.000 claims 1
- 239000007924 injection Substances 0.000 claims 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 29
- 238000005245 sintering Methods 0.000 abstract description 23
- 238000005238 degreasing Methods 0.000 abstract description 16
- 239000000377 silicon dioxide Substances 0.000 abstract description 13
- 238000001746 injection moulding Methods 0.000 abstract description 9
- 238000004898 kneading Methods 0.000 abstract description 8
- 238000005266 casting Methods 0.000 abstract description 3
- 238000010297 mechanical methods and process Methods 0.000 abstract description 3
- 230000002776 aggregation Effects 0.000 abstract description 2
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 abstract 1
- 238000004220 aggregation Methods 0.000 abstract 1
- 239000002245 particle Substances 0.000 description 11
- 230000000052 comparative effect Effects 0.000 description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 6
- 238000005422 blasting Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 5
- DOIRQSBPFJWKBE-UHFFFAOYSA-N dibutyl phthalate Chemical compound CCCCOC(=O)C1=CC=CC=C1C(=O)OCCCC DOIRQSBPFJWKBE-UHFFFAOYSA-N 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 229920005992 thermoplastic resin Polymers 0.000 description 4
- 239000001993 wax Substances 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 235000014113 dietary fatty acids Nutrition 0.000 description 3
- 239000000194 fatty acid Substances 0.000 description 3
- 229930195729 fatty acid Natural products 0.000 description 3
- 150000004665 fatty acids Chemical class 0.000 description 3
- 239000008240 homogeneous mixture Substances 0.000 description 3
- 230000014759 maintenance of location Effects 0.000 description 3
- 238000005058 metal casting Methods 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 3
- 239000008188 pellet Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229910052845 zircon Inorganic materials 0.000 description 3
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229920000877 Melamine resin Polymers 0.000 description 2
- 239000006057 Non-nutritive feed additive Substances 0.000 description 2
- 235000021355 Stearic acid Nutrition 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 229920001519 homopolymer Polymers 0.000 description 2
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 description 2
- ZQKXQUJXLSSJCH-UHFFFAOYSA-N melamine cyanurate Chemical compound NC1=NC(N)=NC(N)=N1.O=C1NC(=O)NC(=O)N1 ZQKXQUJXLSSJCH-UHFFFAOYSA-N 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 2
- 239000012188 paraffin wax Substances 0.000 description 2
- 229920001490 poly(butyl methacrylate) polymer Polymers 0.000 description 2
- 235000011121 sodium hydroxide Nutrition 0.000 description 2
- 239000008117 stearic acid Substances 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 1
- 229920002319 Poly(methyl acrylate) Polymers 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- -1 aliphatic ethers Chemical class 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000000748 compression moulding Methods 0.000 description 1
- 239000007822 coupling agent Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 150000002191 fatty alcohols Chemical class 0.000 description 1
- 230000002496 gastric effect Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000005495 investment casting Methods 0.000 description 1
- ZFSLODLOARCGLH-UHFFFAOYSA-N isocyanuric acid Chemical compound OC1=NC(O)=NC(O)=N1 ZFSLODLOARCGLH-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 150000002734 metacrylic acid derivatives Chemical class 0.000 description 1
- 125000000325 methylidene group Chemical group [H]C([H])=* 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 125000005498 phthalate group Chemical class 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920001485 poly(butyl acrylate) polymer Polymers 0.000 description 1
- 229920001483 poly(ethyl methacrylate) polymer Polymers 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 229920000120 polyethyl acrylate Polymers 0.000 description 1
- 229920000193 polymethacrylate Polymers 0.000 description 1
- 239000004926 polymethyl methacrylate Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 229910000077 silane Inorganic materials 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Mold Materials And Core Materials (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明はセラミックス中子の製造方法に関する。さらに
くわしくは、シリカ質よりなる多孔質セラミックス中子
の５０ａ方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a ceramic core. More specifically, the present invention relates to a method 50a of a porous ceramic core made of siliceous material.
【従来の技術］
精密鋳造用セラミックス中子の特性として、ワックス模
型製造時の強度に耐え、かつ金属鋳造時の寸法精度およ
び耐熱性にすぐれていることが要求されており、現在非
品質シリカを主成分とするセラミックス焼結体が用いら
れている。このようなセラミックス中子は非品質シリカ
を主成分とし、熱硬化性樹脂や熱可塑性樹脂などをバイ
ンダーとして用い、射出成形法や圧縮成形法によってグ
リーン体を成形し、脱脂・焼結させることによって製造
されている。たとえば、特開昭６３−２４８７７５号公
報明細書に示されているように、パラフィンワックス、
ステアリン酸金属塩および脂肪酸よりなるバインダーと
非品質シリカおよびジルコンよりなるセラミックスを射
出成形してなるグリーン体を脱脂・焼結し、セラミック
ス中子を製造する方法が提案されている。[Conventional technology] Ceramic cores for precision casting are required to withstand strength during wax model manufacturing, and have excellent dimensional accuracy and heat resistance during metal casting.Currently, non-quality silica is used. A ceramic sintered body is used as the main component. This kind of ceramic core is made of non-quality silica as a main component, using thermosetting resin or thermoplastic resin as a binder, molding a green body by injection molding or compression molding, degreasing and sintering. Manufactured. For example, as shown in JP-A-63-248775, paraffin wax,
A method has been proposed for manufacturing a ceramic core by degreasing and sintering a green body made by injection molding a binder made of a metal stearate and a fatty acid and a ceramic made of non-quality silica and zircon.
しかしながら、このような内部が緻密な中子を用いた場
合、金属を鋳造した後、中子を除去するためには苛性ソ
ーダ水溶液を用いる方法が一般的であった。苛性ソーダ
水溶液を用いた場合、スラヅジが発生したり、廃液の処
理などで問題があった。このようなことから、セラミッ
クス中子を除去する方法として、加熱後振動を加えるな
どの方法が提案されている（特開昭５２− １５２８２
１号）が、中子が緻密なために充分な効果を期待するこ
とができなかった。However, when such a core with a dense interior is used, a common method of removing the core after casting the metal is to use an aqueous solution of caustic soda. When a caustic soda aqueous solution was used, there were problems such as generation of sludge and treatment of waste liquid. For this reason, methods such as applying vibration after heating have been proposed as a method for removing the ceramic core (Japanese Patent Laid-Open No. 52-15282).
No. 1), but because the core was dense, sufficient effects could not be expected.
［発明が解決しようとする課題１
これらのことから、複雑な形状を有し、ワックス型製造
時の強度に耐え、金属鋳造後の中子の除去を加熱・振動
やショットブラストなどの機械的方法で容易に行うこと
が可能なセラミックス中子を得ることはいまだに解決さ
れていない。[Problem to be solved by the invention 1] For these reasons, it is necessary to have a complex shape, withstand the strength during wax mold manufacturing, and to remove the core after metal casting using mechanical methods such as heating, vibration, or shot blasting. Obtaining a ceramic core that can be easily performed in the process has not yet been solved.
以上のことから、本発明は、これらの欠点がなく、すな
わち複雑な形状を有し、かつ金属鋳造後の中子除去が加
熱・振動やショットブラストなどの機械的方法で除去す
ることができるセラミックス中子の製造方法を提案する
ことを目的とするものである。Based on the above, the present invention has been developed to create ceramics that do not have these drawbacks, have a complex shape, and whose core can be removed by mechanical methods such as heating, vibration, or shot blasting after metal casting. The purpose is to propose a method for manufacturing cores.
［課題を解決するための手段および作用］本発明にした
がえば、これらの課題は、（Ａ）焼結性シリカ質、（Ｂ
）昇華温度が１５０℃以上である昇華性物質およびＦＣ
＋バインダーとからなる焼結性物質含有混合物を射出成
形させ、得られる成形体を脱脂・焼結させることによる
セラミックス中子の製造方法であり、該混合物中のバイ
ンダーの混合割合は５．０〜４０重１％であり、かつ焼
結性シリカ質および昇華性物質の合計量中に占める昇華
性物質の割合は１０〜７０重量％であるが、全混合物中
の焼結性シリカ質の混合割合は少な《とも５０重量％で
あることを特徴とするセラミックス中子の製造方法、に
よって解決することができる。以下、本発明を具体的に
説明する。[Means and effects for solving the problems] According to the present invention, these problems are solved by (A) sinterable siliceous material, (B
) Sublimable substances and FCs whose sublimation temperature is 150°C or higher
This is a method for manufacturing a ceramic core by injection molding a mixture containing a sinterable substance consisting of a binder and a binder, and degreasing and sintering the obtained molded body, and the mixing ratio of the binder in the mixture is 5.0 to 5.0. 40% by weight and 1% by weight, and the proportion of the sublimable substance in the total amount of the sinterable siliceous substance and the sublimable substance is 10 to 70% by weight, but the mixing proportion of the sinterable siliceous substance in the total mixture can be solved by a method for producing a ceramic core characterized in that the content is at least 50% by weight. The present invention will be explained in detail below.
本発明における焼結性物質含有混合物は本質的に焼結性
シリカ質、昇華性物質およびバインダーからなる。The sinterable material-containing mixture in the present invention essentially consists of a sinterable siliceous material, a sublimable material, and a binder.
（Ａｌ焼結性シリカ質
本発明において使われる焼結性シリカ質は本質的にシリ
カよりなり、アルミナ、ジルコニア、ムライト、ジルコ
ン（ジルコニア・シリカ）などを一種または二種以上含
有するものである。該焼結性シリカ質中のシリカの含有
量はＳｉＯｚとして少な《とも６０重量％である。焼結
性シリカ質中のシリカの含有徹が６０重量％未満の場合
では、金属鋳造のさい、中子にクラックが発生し易いた
めに好ましくない。該焼結性シリカ質の平均粒径は０．
１〜５００４ｇ＋であり、０．１〜２００ μｍが好ま
しく、特にｏ．＋−ｉｏｏμＩが好適である。焼結性シ
リカ質の平均粒径が０．１ｕｍ未満の場合では、混合物
を製造するさいに混線時において分散が困難である。一
方、５００μｍを超えると、中子成形体を焼結するさい
に保形性がよくない。(Al Sinterable Siliceous Material The sinterable siliceous material used in the present invention essentially consists of silica, and contains one or more kinds of alumina, zirconia, mullite, zircon (zirconia/silica), etc. The content of silica in the sinterable siliceous material is at least 60% by weight as SiOz.If the silica content in the sinterable siliceous material is less than 60% by weight, it is This is not preferable because cracks are likely to occur in the particles.The average particle size of the sinterable siliceous material is 0.
1 to 5004 g+, preferably 0.1 to 200 μm, particularly o. +-iooμI is preferred. If the average particle size of the sinterable siliceous substance is less than 0.1 um, it is difficult to disperse the mixture during crosstalk during production of a mixture. On the other hand, if it exceeds 500 μm, shape retention is poor when sintering the core molded body.
（ロ）昇華性物質
また、本発明において用いられる昇華性物質の融点は１
５０℃以上であり、 １６０℃以上が望まし《、とりわ
け１７０℃以上が好適である。昇華温度が１５０℃未満
の胃華性物質を用いると、焼結性物質と混練したり、後
記の射出成形を行うさいに内部にボイドが発生するなど
の問題がある。また、昇償澗度の上限は一般には８［）
０℃である。昇華冫品度が８００℃を超えた昇華性物質
を用いると、焼結不能になるために好まし《ない。好適
な昇華性物質としては、メラミン、シアヌール酸、メラ
ミンシアヌレートなどをあげることができる。(b) Sublimable substance The melting point of the sublimable substance used in the present invention is 1
The temperature is 50°C or higher, preferably 160°C or higher, and particularly preferably 170°C or higher. If a gastric material with a sublimation temperature of less than 150° C. is used, there are problems such as voids occurring inside the material when it is kneaded with a sinterable material or during injection molding as described below. In addition, the upper limit of the rate of increase is generally 8 [)
It is 0°C. It is not preferable to use a sublimable substance with a sublimation grade of over 800° C. because sintering becomes impossible. Suitable sublimable substances include melamine, cyanuric acid, melamine cyanurate, and the like.
該昇華性物質の平均粒径は、通常０．５〜１００μｍで
あり、０．５〜８０μｍが好ましい。平均粒径が０．５
ｕａ＋未満の昇華性物質を使用すると、混練が困難であ
る。一方、 １００μｍを超えた昇華性物質を使うと、
脱脂焼結時の保形性が低下すると共に焼結体の密度が低
下するために好まし《ない。The average particle size of the sublimable substance is usually 0.5 to 100 μm, preferably 0.5 to 80 μm. Average particle size is 0.5
If a sublimable substance with less than ua+ is used, kneading will be difficult. On the other hand, if a sublimable substance with a diameter exceeding 100 μm is used,
This is not preferable because the shape retention during degreasing and sintering decreases and the density of the sintered body decreases.
（Ｃ） バインダー
さらに、バインダーとして使用可能な樹脂としては、メ
チレン系重合体、スチレン系重合体、ブロビレン系重合
体、エチレンー酢酸ビニル共重合体、アルキル（一般に
は、炭素数 ６個以下）メタアクリレートを主成分（５
（ｌ重量％以上）とする重合体（たとえば、ポリメチル
メタクリレート、ポリエチルメタクリレート、ポリブチ
ルメタクリレート）およびアルキル（通常炭素数 ６個
以下）アクリレートを主成分（５０重量％以上）とする
重合体（たとえば、ポリメチルアクリレート、ポリエチ
ルアクリレート、ポリブチルアクリレート）があげられ
る。以上において、“系重合体”とは該モノマーの単独
重合体および該モノマーを主成分（少なくとも５０重量
％）とし、他のモノマーの単独重合体を意味する。これ
らのバインダーの数平均分子量［蒸気圧浸透法（ ｖａ
ｐｏｒｐｒｅｓｓｕｒｅ ｏｓｍｏｍｅｔｅｒ法）によ
って測定］は通常２０００ないし５０万であり、４００
０以上のものが好ましい。これらのバンダーはセラミッ
クス材料と混合して焼結物質を製造する分野において広
く使われているものである。(C) Binder Further, resins that can be used as binders include methylene polymers, styrene polymers, brobylene polymers, ethylene-vinyl acetate copolymers, and alkyl (generally having 6 or less carbon atoms) methacrylates. is the main component (5
(1% by weight or more) (for example, polymethyl methacrylate, polyethyl methacrylate, polybutyl methacrylate) and polymers whose main component (50% by weight or more) is alkyl (usually 6 or less carbon atoms) acrylate ( Examples include polymethyl acrylate, polyethyl acrylate, polybutyl acrylate). In the above, the term "system polymer" refers to a homopolymer of the monomer and a homopolymer containing the monomer as a main component (at least 50% by weight) and other monomers. The number average molecular weight of these binders [vapor pressure osmosis (VA)
[measured by porpressure osmometer method] is usually 2,000 to 500,000, and 400,000 to 500,000
It is preferably 0 or more. These banders are widely used in the field of producing sintered materials by mixing with ceramic materials.
（Ｄｌ混合割合
本発明の焼結性物質含有混合物において、焼結性シリカ
質と昇華性物質との合計量中に占める昇華性物質の混合
割合は１０〜７０重量％であり、１０〜６５重量％が望
ましく、とりわけ１０〜６０重量％が好適である。焼結
性シリカ質と昇華性物質との合計量中に占める昇華性物
質の混合割合がＩＯ重量％未満では、加熱・振動やショ
ッ１・ブラストで中子が破壊されない。一方、７０重量
％を超えるならば、焼結が困難になるとともに、ワック
ス型製作時に中子が破壊されてしまう。(Dl mixing ratio In the sinterable material-containing mixture of the present invention, the mixing ratio of the sublimable material in the total amount of the sinterable siliceous material and the sublimable material is 10 to 70% by weight, and is 10 to 65% by weight. %, particularly preferably 10 to 60% by weight.If the mixing ratio of the sublimable material in the total amount of the sinterable siliceous material and the sublimable material is less than IO% by weight, heating, vibration or shock - The core will not be destroyed by blasting. On the other hand, if it exceeds 70% by weight, sintering will be difficult and the core will be destroyed during wax mold production.
また、焼結性物質含有混合物中に占めるバインダーの混
合割合は５〜４０重屑％であり、１０〜４０重晴％が望
ましく、とりわけ１０〜３０重量％が好適である。焼結
性物質含有混合物に占めるバインダの混合割合が５重量
％未満では、混合物の混線性、成形性および分散性が悪
いばかりでなく，均＝−な混合物を製造することが困難
であり、たとえ均一な混合物が得られたとしても、良好
なグリーン体を得ることができない。一方、４０市量部
を超えると，グリーン体物質（強度、保形性）はよいが
、脱バインダー後の密度が低く、さらに焼結しにくい。The mixing ratio of the binder in the sinterable substance-containing mixture is 5 to 40% by weight, preferably 10 to 40% by weight, and particularly preferably 10 to 30% by weight. If the proportion of the binder in the sinterable substance-containing mixture is less than 5% by weight, the mixture will not only have poor crosstalk, formability, and dispersibility, but will also have difficulty producing a homogeneous mixture. Even if a homogeneous mixture is obtained, a good green body cannot be obtained. On the other hand, if it exceeds 40 parts by weight, the green body material (strength, shape retention) is good, but the density after removing the binder is low and it is difficult to sinter.
該焼結性物質含有混合物中の焼結性シリカ獅質の混合割
合は少な《とも５０重量％であり、５５重π％以上が望
まし《、とりわけ６０重量％が好適である。該焼結性物
質含有混合物中の焼結性シリカ質閣の混合割合が５０重
量％未満では、焼結が困難になるとともに、脱脂・焼結
時に有害な変形が発生する。The mixing ratio of the sinterable silica in the mixture containing the sinterable substance is at least 50% by weight, preferably 55% by weight or more, and particularly preferably 60% by weight. If the mixing ratio of sinterable silica in the sinterable material-containing mixture is less than 50% by weight, sintering becomes difficult and harmful deformation occurs during degreasing and sintering.
ｆＥＩ Ｕ合物の′ｌＡ造
本発明の焼結性物質含有混合物を製造するには、以上の
焼結性シリカ質、胃前性物質およびバインダーを均一に
混合すればよい。混合方法としては、全混合成分を同時
に混合してもよ《、また、混合成分のうちの一部をあら
かじめ混合して得られる混合物に残りの混合成分を混合
させてもよい（たとえば、焼結性シリカ質と昇華性物質
とを混合して得られる混合物にバインダーを混合する）
。Preparation of fEI U Composite In order to produce the sinterable material-containing mixture of the present invention, the above-described sinterable siliceous material, pregastric material, and binder may be uniformly mixed. As for the mixing method, all the mixed components may be mixed at the same time, or some of the mixed components may be mixed in advance and the remaining mixed components may be mixed into a mixture obtained (for example, by sintering). A binder is mixed into the mixture obtained by mixing a siliceous substance and a sublimable substance.)
.
さらに、必要に応じて，脂肪酸アミド、脂肪酸またはそ
のエステル、脂肪族アルコール、フタル酸エステル、脂
肪族エーテル、バラフィンワックス、シラン系またはチ
タネート系カップリング剤などのハロゲンを含有しない
加工助剤を添加することができる。このさい、加工助剤
の添加量は焼結性シリカ質１００ｆｆｉｆｆｉ部に対し
て多くとも２０市量部であり、特に１０重川部以下が好
ましい。Furthermore, if necessary, halogen-free processing aids such as fatty acid amides, fatty acids or their esters, fatty alcohols, phthalates, aliphatic ethers, paraffin wax, silane-based or titanate-based coupling agents are added. can do. At this time, the amount of the processing aid added is at most 20 parts by weight per 100 parts of the sinterable siliceous material, and preferably 10 parts by weight or less.
混合方法としては熱可塑性樹脂の分野において［９に使
われているヘンシェルミキサーのごとき混合機を用いて
ドライブレンドさせても製造することができるし、バン
バリーミキサー、ニダー、ロールミルおよびスクリュー
式押出機のごとき混合機を使用して溶融混練させても得
ることができる。このさい、あらかじめドライブレンド
し、得られる混合物を溶融混練させることによって均一
状の混合物を得ることができる。この場合、一般には溶
融混練させた後ペレット状物に成形し、後記の射出成形
に供する。As a mixing method, it can be produced by dry blending using a mixer such as the Henschel mixer used in the thermoplastic resin field [9], or by dry blending using a mixer such as the Henschel mixer used in the thermoplastic resin field [9], or by dry blending using a mixer such as the Henschel mixer used in the thermoplastic resin field [9], or by dry blending using a mixer such as the Henschel mixer used in It can also be obtained by melting and kneading using a mixer such as the following. At this time, a homogeneous mixture can be obtained by dry blending in advance and melt-kneading the resulting mixture. In this case, the mixture is generally melt-kneaded and then molded into pellets, which are then subjected to injection molding as described below.
ｆＦ）射出成形
このようにして得られる焼結性物質含有混合物は合成樹
脂の分野において通常実施されている射出成形法によっ
て各種の形状を有する中子用成形体に賦形される。なお
、前記の溶融混練する場合でも、成形する場合でも、使
用されるバインダーの軟化点以上の温度であるが、焼結
性シリカ質の界范温度よりも低い温度範囲で実施する必
要がある。これらのことから、溶融混練およびｑ＝ｔ出
成形は１００〜２５０℃の温度範囲で実施すればよい。fF) Injection molding The mixture containing the sinterable substance thus obtained is shaped into molded bodies for cores having various shapes by an injection molding method commonly practiced in the field of synthetic resins. In addition, both in the case of melt-kneading and in the case of molding, it is necessary to carry out the process at a temperature that is higher than the softening point of the binder used, but lower than the critical temperature of the sinterable siliceous material. For these reasons, melt kneading and q=t extrusion molding may be carried out in a temperature range of 100 to 250°C.
得られる中子用成形体の厚さは一般には０．２〜２００
ｍｍであり、 ０． ５ 〜１５０ｎ＋ｍが好まし《
、特に１．０〜１５０ ｍｍが好適である。この成形体
の厚さが２００ｍｍを超えるならば、後記の脱脂、焼結
を行なった場合、成形体の表面にフクレが発生したり、
クラックが発生する。該成形体の形状は特に限定するも
のでないが、その代表例として扱状、棒状、箱状、バイ
ブ状、円筒状などがあり、その他の複雑な形状を有する
ものでもよい。The thickness of the obtained molded body for core is generally 0.2 to 200 mm.
mm and 0. 5 to 150n+m is preferable《
, particularly preferably 1.0 to 150 mm. If the thickness of this molded body exceeds 200 mm, blisters may occur on the surface of the molded body when degreasing and sintering described below are performed.
Cracks occur. The shape of the molded body is not particularly limited, but representative examples thereof include a handle shape, a rod shape, a box shape, a vibrator shape, a cylindrical shape, etc., and other complicated shapes may be used.
このようにして得られた中子用成形体は後記の脱脂およ
び焼結に供せられる。The core molded body thus obtained is subjected to degreasing and sintering described later.
ｆＧ］脱脂
得られた中子用成形体は室温より雰囲気の温度を上昇さ
せ、本質的にバインダーおよび昇華性物質がな《なるま
で脱脂を実施する。このさい、脱脂の最高温度は通常２
００”Ｃ以上である。一般に、中子用成形体の厚さが厚
い程、最高温度が高い温度まで脱脂する必要がある。ま
た、温度の上昇速度は通常１時ｕ■当りｌ−１ｆ１０℃
（好ましくは、１〜８０℃）である。上昇速度は成形体
の厚さが薄い場合では、速い速度で上昇させてもよいが
、厚い場合では、成形体にフクレなどの変形が発生する
。この脱脂工程は１気圧下で行なってもよ《、減圧下ま
たは加圧下で実施してもよい。さらに、アルミナのごと
く酸化物を焼結性物質として使用する場合、空気中で行
なってもよいが、窒化珪素、炭化珪素のごとき非酸化物
を用いる場合、窒素、アルゴンなどの不活性ガスの雰囲
気中で行なうことが好ましい。fG] Degreasing The obtained core molded body is degreased by raising the temperature of the atmosphere above room temperature until the binder and sublimable substance are essentially eliminated. At this time, the maximum temperature for degreasing is usually 2
00"C or higher. In general, the thicker the core molding, the higher the maximum temperature it is necessary to degrease. Also, the rate of temperature rise is usually 1-1f10°C per hour u.
(preferably 1 to 80°C). If the molded product is thin, the rising speed may be increased quickly, but if the molded product is thick, deformation such as blistering may occur in the molded product. This degreasing step may be carried out under 1 atm, reduced pressure or increased pressure. Furthermore, when using an oxide such as alumina as the sinterable substance, the sintering process may be carried out in air, but when using a non-oxide such as silicon nitride or silicon carbide, an atmosphere of an inert gas such as nitrogen or argon is used. It is preferable to do it inside.
この脱脂は成形体が比較的に薄い場合、成形体中に可成
りのバインダーおよび昇華性物質が残存してもよいが、
比較的に厚い場合では、成形体中にバインダーおよび昇
華性物質が本質的になくなるまで脱脂する必要がある。This degreasing may leave a considerable amount of binder and sublimable substances in the molded product if the molded product is relatively thin.
In relatively thick cases, it may be necessary to degrease the molded body until it is essentially free of binder and sublimable material.
前者の場合でも、成形体中に残存するバインダーおよび
昇華性物質の含有量は５重量％以下である。Even in the former case, the content of the binder and sublimable substance remaining in the molded article is 5% by weight or less.
（旧焼結
このようにして脱脂された中子用成形体は一般に行なわ
れている方法に従って焼結される。焼結はシリカ質に添
加されている他の焼結性物質の量と種類によって異なる
が、一般には９００〜１，４００℃の温度範囲で行なわ
れる。(Former sintering) The core molded body thus degreased is sintered according to a commonly practiced method. Sintering depends on the amount and type of other sinterable substances added to the siliceous material. Generally, the temperature range is 900 to 1,400°C.
［実施例および比較例］
以下、実施例によって本発明をさらに《わし《説明する
。[Examples and Comparative Examples] The present invention will be further explained below with reference to Examples.
なお、実施例および比較例において、気孔径は．ＪＩＳ
Ｒ−２２０５にしたがって測定した。In addition, in the examples and comparative examples, the pore diameter is . JIS
Measured according to R-2205.
脱脂は電気炉（内容ｆｌ ２，０００ ｃｃ）を使っ
て窒素の雰囲気下で２０℃／時間で４５時間かけて５０
０℃まで昇濡させた。また、焼結は上記と同じ電気炉を
用い、大気圧下で９０℃／時間で昇温させた。Degreasing was performed using an electric furnace (content fl 2,000 cc) under a nitrogen atmosphere at 20°C/hour for 45 hours.
The temperature was raised to 0°C. Further, the sintering was performed using the same electric furnace as above, and the temperature was raised at a rate of 90° C./hour under atmospheric pressure.
実施例および比較例において使用した焼結性シリカ質、
昇華性物質およびバインダーの種類および物性を下記に
示す。Sinterable siliceous material used in Examples and Comparative Examples,
The types and physical properties of the sublimable substance and binder are shown below.
［（Ａ）焼結性シリカ質］
焼・粘性シリカ質として、平均粒径が１８μＩであり，
非晶質シリカ６５重量％、かつ平均粒径がｌμＩであり
、しかもアルミナ５重量％および平均粒径がｌロμｍで
あるジルコニア３０重１％よりなる混合物〔以下「シリ
カ質（ａ）」と云う１ならびに上記非晶性シリカ８０重
喰％および平均粒径が５μｍであるジルコン２０重量％
よりなる混合物［以下［シリカ質（ｂ）」と云う］を使
った。[(A) Sinterable siliceous material] As a sintered and viscous siliceous material, the average particle size is 18 μI,
A mixture consisting of 65% by weight of amorphous silica and 1% by weight of amorphous silica with an average particle size of lμI, 5% by weight of alumina and 30% by weight of zirconia with an average particle size of lμm [hereinafter referred to as "siliceous material (a)"] 1 and 80% by weight of the amorphous silica and 20% by weight of zircon with an average particle size of 5 μm.
A mixture [hereinafter referred to as [siliceous substance (b)]] was used.
［（Ｂ）昇華性物質〕
また、昇華性物質として、平均粒径が２．３ａｍであり
、かつ昇壱温度が３５０℃であるメラミンシアヌレート
（以下「化合物（ｌ）」と云う）および平均粒径が１．
８μｍであり、かつ昇＠温度が２２０℃であるメラミン
（以下「化合物（２）」と云う）を用いた。[(B) Sublimable substance] In addition, as a sublimable substance, melamine cyanurate (hereinafter referred to as "compound (l)") having an average particle size of 2.3 am and a sublimation temperature of 350 ° C. The particle size is 1.
Melamine (hereinafter referred to as "compound (2)") having a thickness of 8 μm and a temperature rise of 220° C. was used.
［（Ｃ）バインダー］
さらに、バインダーとして、平均分子量が約２０万であ
るボリメタアクリル酸ブチルｌ００重量部に１５重量部
のジブチルフタレートおよび３０重遣部のステアリン酸
を添加したバインダー（以下「バインダー（Ａ）」と云
う）および該ボリメタアクリル酸ブチル５０重看部、平
均分子量が２万であるアモルファスボリブロビレン５０
重量部にジブチルフタレートＩＯ市量部およびステアリ
ン酸１５重量部を添加したバインダー（以下「バインダ
ー（Ｂ）」と云う）を使用した。[(C) Binder] Further, as a binder, a binder (hereinafter referred to as "binder") is prepared by adding 15 parts by weight of dibutyl phthalate and 30 parts by weight of stearic acid to 100 parts by weight of butyl polymethacrylate having an average molecular weight of about 200,000. (A)") and 50 parts of polybutyl methacrylate, and 50 parts of amorphous polybrobylene having an average molecular weight of 20,000.
A binder (hereinafter referred to as "binder (B)") containing 15 parts by weight of dibutyl phthalate IO and 15 parts by weight of stearic acid was used.
実施例１〜６、比較例１〜４
第１表に種類および焼結性シリカ質とＷ’Ｊ性物質との
合計量中に占める配合割合が示されている焼結性シリカ
質ならびに第１表に種類が示されている昇華性物質なら
びに第１表に種類および焼結性シリカ質、昇華性物質お
よびバインダーとの合計量中に占める配合割合が示され
るバインダーをあらかじめヘンシェルミキサーを使って
それぞれ２分間ドライブレンドを行なった。得られた各
混合物をベント付二軸押出ＩＩ（径 ３５ｍｍ）を用い
て１５０℃の温度において混練しながらペレットを製造
した。それぞれのペレットを射出成形機（樹脂温度 １
５０℃）を使用して両端部の外径が８ｍ＋＋＋、中央部
の外径が１５ｍｏ＋％内径が４ｍｍ、長さが５Ｏｎ＋ｍ
のバイブ状の中子を作成した。得られた各中子用成形体
を脱脂炉を使って前記の条件で脱脂・焼結を行ない、セ
ラミックス中子を製造した。得られた各多孔質中子の外
観および気孔率を第１表に示す。また、これらの中子を
用いて外径が４０＋ｍｎの耐熱鋼棒状体をワックス型で
製造し、鋳造した。得られた鋳造体に約１ｍｍのショッ
トを吹きつけ、中子の除去状態を観察した。全実施例で
得られた中子の外観はすべて良好であり、ショットブラ
スト後の中子の除去状態では、完全に除去することがで
きた。しかし、比較例ｌでは、中子にクラックが発生し
、鋳造テストを実施しなかった。また、比較例２では、
中子の外観は良好であったが、ショットブラスト後の中
子の除去が不完全であった。なお、比較例３では混線が
不可能であった。Examples 1 to 6, Comparative Examples 1 to 4 Sinterable siliceous materials and first The sublimable substances whose types are shown in the table and the binders whose types and proportions in the total amount of sinterable silica, sublimable substances and binder are shown in Table 1 are prepared in advance using a Henschel mixer. Dry blending was performed for 2 minutes. Pellets were produced by kneading each of the obtained mixtures at a temperature of 150° C. using a vented twin-screw extruder II (diameter: 35 mm). Place each pellet into an injection molding machine (resin temperature 1
50℃), the outer diameter at both ends is 8m+++, the outer diameter at the center is 15mo+%, the inner diameter is 4mm, and the length is 5On+m.
A vibrator-shaped core was created. Each of the obtained core molded bodies was degreased and sintered using a degreasing furnace under the above conditions to produce a ceramic core. Table 1 shows the appearance and porosity of each porous core obtained. Further, using these cores, a heat-resistant steel rod-shaped body having an outer diameter of 40+mm was produced in a wax mold and cast. A shot of approximately 1 mm was sprayed onto the obtained cast body, and the state of removal of the core was observed. The appearance of the cores obtained in all Examples was good, and the cores could be completely removed after shot blasting. However, in Comparative Example 1, cracks occurred in the core, and no casting test was conducted. In addition, in Comparative Example 2,
Although the appearance of the core was good, removal of the core after shot blasting was incomplete. Note that in Comparative Example 3, crosstalk was impossible.
さらに、比較例４では、脱脂時において中子用成形体が
変形した。Furthermore, in Comparative Example 4, the core molded body was deformed during degreasing.
（以下余白）
〔発明の効果〕
本発明方法によって得られるセラミックス中子は、その
混合物および成形体の製造ならびに焼結後の特性を含め
て下記のごとき効果を発揮する。(The following is a blank space) [Effects of the Invention] The ceramic core obtained by the method of the present invention exhibits the following effects, including the properties after production of the mixture and molded body and sintering.
ｆｉｌ １練性がすぐれ、かつ二次凝集などの発生がな
い。fil 1 Excellent kneading properties and no secondary agglomeration.
（２）流動特性が良好なために複雑な形状を有する中子
についても賦形が容易である。(2) Since the flow characteristics are good, it is easy to shape even a core having a complicated shape.
（３）気孔率の制［卸が容易であり、ショットブラスト
による中子の破壊除去を制御することができる。(3) Control of porosity [Easy to disassemble, and destruction and removal of the core by shot blasting can be controlled.
本発明方法によるセラミックス中子は以上のごとき効果
を発揮するために多方面にわたって利用することができ
る。代表的な用途を下記に示す。The ceramic core produced by the method of the present invention can be used in a wide variety of ways to achieve the above-mentioned effects. Typical uses are shown below.
（ｌ）自動車用部品 （２）家庭用電気ｍ器用部品 ｛３｝その他の各種工業用部品(l) Automotive parts (2) Household electrical equipment parts {3} Other various industrial parts
Claims (1)
である昇華性物質および（Ｃ）バインダーとからなる焼
結性物質含有混合物を射出成形させ、得られる成形体を
脱脂・焼結させることによるセラミックス中子の製造方
法であり、該混合物中のバインダーの混合割合は５．０
〜４０重量％であり、かつ焼結性シリカ質および昇華性
物質の合計量中に占める昇華性物質の割合は１０〜７０
重量％であるが、全混合物中の焼結性シリカ質の混合割
合は少なくとも５０重量％であることを特徴とするセラ
ミックス中子の製造方法。A sinterable substance-containing mixture consisting of (A) a sinterable siliceous substance, (B) a sublimable substance with a sublimation temperature of 150°C or higher, and (C) a binder is injection molded, and the resulting molded body is degreased and sintered. This is a method for manufacturing a ceramic core by binding, and the mixing ratio of the binder in the mixture is 5.0.
~40% by weight, and the proportion of the sublimable substance in the total amount of the sinterable siliceous substance and the sublimable substance is 10 to 70%.
% by weight, and the mixing ratio of sinterable siliceous material in the total mixture is at least 50% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10897589A JPH02290642A (en) | 1989-04-27 | 1989-04-27 | Manufacture of ceramic core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10897589A JPH02290642A (en) | 1989-04-27 | 1989-04-27 | Manufacture of ceramic core |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02290642A true JPH02290642A (en) | 1990-11-30 |
Family
ID=14498399
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10897589A Pending JPH02290642A (en) | 1989-04-27 | 1989-04-27 | Manufacture of ceramic core |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02290642A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011104657A (en) * | 1998-11-20 | 2011-06-02 | Rolls-Royce Corp | Apparatus for casting mold |
| JP2011230982A (en) * | 2010-04-30 | 2011-11-17 | Noritake Co Ltd | Injection molding material for manufacturing porous ceramic, injection molding method, and method of manufacturing the porous ceramic |
| JP2011256077A (en) * | 2010-06-09 | 2011-12-22 | Noritake Co Ltd | Ceramic composite for porous ceramic production, injection molding material, method of molding molding material for porous ceramic production and method of producing porous ceramic |
| JP2012161805A (en) * | 2011-02-04 | 2012-08-30 | Hitachi Metals Ltd | Ceramic core and method for manufacturing the same |
| JP2014529567A (en) * | 2011-08-25 | 2014-11-13 | 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Ｒｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Ceramic composition |
-
1989
- 1989-04-27 JP JP10897589A patent/JPH02290642A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011104657A (en) * | 1998-11-20 | 2011-06-02 | Rolls-Royce Corp | Apparatus for casting mold |
| JP2011230982A (en) * | 2010-04-30 | 2011-11-17 | Noritake Co Ltd | Injection molding material for manufacturing porous ceramic, injection molding method, and method of manufacturing the porous ceramic |
| JP2011256077A (en) * | 2010-06-09 | 2011-12-22 | Noritake Co Ltd | Ceramic composite for porous ceramic production, injection molding material, method of molding molding material for porous ceramic production and method of producing porous ceramic |
| JP2012161805A (en) * | 2011-02-04 | 2012-08-30 | Hitachi Metals Ltd | Ceramic core and method for manufacturing the same |
| JP2014529567A (en) * | 2011-08-25 | 2014-11-13 | 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Ｒｏｂｅｒｔ Ｂｏｓｃｈ Ｇｍｂｈ | Ceramic composition |
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