JPH027000B2 - - Google Patents
Info
- Publication number
- JPH027000B2 JPH027000B2 JP15776582A JP15776582A JPH027000B2 JP H027000 B2 JPH027000 B2 JP H027000B2 JP 15776582 A JP15776582 A JP 15776582A JP 15776582 A JP15776582 A JP 15776582A JP H027000 B2 JPH027000 B2 JP H027000B2
- Authority
- JP
- Japan
- Prior art keywords
- silicon carbide
- heat
- heat exchanger
- resistant material
- silicon
- 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.)
- Expired
Links
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 29
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 29
- 239000003779 heat-resistant material Substances 0.000 claims description 11
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 8
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 8
- 238000005229 chemical vapour deposition Methods 0.000 claims description 6
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- 239000012530 fluid Substances 0.000 claims 2
- 238000005192 partition Methods 0.000 claims 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims 1
- 239000000463 material Substances 0.000 description 9
- 239000011248 coating agent Substances 0.000 description 7
- 238000000576 coating method Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 5
- 229910010293 ceramic material Inorganic materials 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 229910052878 cordierite Inorganic materials 0.000 description 2
- JSKIRARMQDRGJZ-UHFFFAOYSA-N dimagnesium dioxido-bis[(1-oxido-3-oxo-2,4,6,8,9-pentaoxa-1,3-disila-5,7-dialuminabicyclo[3.3.1]nonan-7-yl)oxy]silane Chemical compound [Mg++].[Mg++].[O-][Si]([O-])(O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2)O[Al]1O[Al]2O[Si](=O)O[Si]([O-])(O1)O2 JSKIRARMQDRGJZ-UHFFFAOYSA-N 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910000856 hastalloy Inorganic materials 0.000 description 1
- 238000005338 heat storage Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910001026 inconel Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F21/00—Constructions of heat-exchange apparatus characterised by the selection of particular materials
- F28F21/04—Constructions of heat-exchange apparatus characterised by the selection of particular materials of ceramic; of concrete; of natural stone
Landscapes
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
Description
本発明は熱交換器の改良にかかるものである。
一般に熱交換器は高熱伝導性を有するものとして
銅、銅合金等が低温（２〜300℃）用として、又、
高温用（1000℃以下）用としてインコネル、ハス
テロイ等の金属材料が使用されている。又、特に
1000℃以上の高温用としては金属の耐熱限界を超
えることから、コージライト、炭化珪素等のセラ
ミツクス材料が知られている。このセラミツクス
材料は、一般には耐熱、耐蝕性にはすぐれている
が、加工性に難点があり複雑な形状には適さな
い。又、熱交換器は高度の信頼性が要求され、し
かも長寿命のものであることが必要であり、これ
らの点で従来のセラミツク材料では満足すべきも
のは得られていなかつた。例えば、コージライト
質のものは低膨脹性であるため耐スポール性には
満足できるにしても、均質性に乏しく実用に耐え
るものは得られていない。
又、炭化珪素質のものは熱伝導性には良好であ
るが、粘土等で焼結したものは熱間荷重に弱く、
又通気性も解決されていない。特に高温において
は酸化されて粒子表面にSiO2の被膜が形成され、
これが順次内部の炭化珪素粒の表面も酸化される
ようになり、この成形体表面と内部との応力の差
が次第に拡大し、ついには破壊に至る等持てる特
性を充分に発揮し得ない状態であつた。
本発明は耐熱性材料基材の特性を充分に生かす
べく、これを改善することによつて従来に見られ
ない熱交換器を開発したもので、耐熱性材料基材
の表面にCVD（化学蒸着）法によつて純度99.95
％以上でFe含有量50PPM以下の炭化珪素被覆を
形成させたものである。即ち、通常セラミツク質
耐熱性材料は気孔の存在を無視し得ず、従つて特
に炭化珪素、炭素、窒化珪素等の非酸化物系材料
の場合には高温において酸化を受け易い。
従つて、本発明においては耐熱性材料の表面に
高純度、高密度の炭化珪素被膜を形成させること
によつて酸素の内部への浸透を抑制しようとする
ものである。
この場合、被膜が容易に酸化されて剥離するよ
うなものでは効果が期待できないから、これを満
足させるためにはCVD（化学蒸着）法によつて純
度を99.95％以上の緻密なものとし、しかも、こ
れが表面から酸化を受けた場合形成されるSiO2
が不純物の存在によつて容易に変質し応力のバラ
ンスを崩してクラツク発生の原因となるため、特
に変質を受け易いFeの含有率を50PPM以下と限
定したものである。
本発明においては基材を被膜との熱膨脹差、安
定性等を勘案すると共に被膜の純度と酸化スピー
ドとの間に密接な関係があることを見出した結果
なされたもので、その結果、従来のセラミツク材
料には見られない長寿命の熱交換器を得たもので
ある。
基材となるべき耐熱性材料は被膜の緻密質炭化
珪素との結合力が強固なもの程好ましいから、炭
化珪素が最適で、その中でも特に炭化珪素の気孔
中に6.5〜35重量％の金属シリコンを含浸せしめ
たもの、炭化珪素が自焼結法によつて嵩密度3.05
ｇ／c.c.以上としたもの、或いは炭化珪素に窒化珪
素を配合又は結合材として含ませたもの等が良
い。
又、被覆される炭化珪素被膜自身に気孔が多数
存在するものは酸化抵抗力が期待できないから、
その気孔率は1.5％以下となるようにCVD工程に
いおいて留意することが必要である。
以下に本発明の実施例につき説明する。熱交換
器用の構成パーツとして金属シリコンの含有割合
10重量％の再結晶炭化珪素体を用意した。これを
CH3SiCl3gas10c.c.／minをH2gasをキヤリヤーgas
として1300℃、20Torrの減圧下で炭化珪素被膜
を形成させた。
表に示すように被膜中のFe分及び気孔率をそ
れぞれ変化させた。これを接着等の加工を行つて
二重管式熱交換器を組立てその評価を行つた。そ
の結果を表に示す。評価は入口温度1200℃の乾燥
空気によつて室温の空気を加熱した場合における
被膜のクラツク発生迄の日数とした。
同時に基材として自焼結炭化珪素（嵩密度3.10
ｇ／c.c.）、再結晶炭化珪素（気孔率20％）、窒化珪
素結合炭化珪素（窒化珪素30％）を使用し、同様
にCVD処理してFe分30PPM含有の炭化珪素被膜
（気孔率１％以下）を形成させて寿命を測定した。
その結果を表に並べて示す。
The present invention relates to improvements in heat exchangers.
In general, heat exchangers are made of copper, copper alloys, etc., which have high thermal conductivity, and are used for low temperatures (2 to 300 degrees Celsius).
Metal materials such as Inconel and Hastelloy are used for high temperature applications (below 1000°C). Also, especially
Ceramic materials such as cordierite and silicon carbide are known for use at high temperatures of 1000°C or higher, as they exceed the heat resistance limit of metals. This ceramic material generally has excellent heat resistance and corrosion resistance, but has difficulty in processing and is not suitable for complex shapes. Furthermore, heat exchangers are required to have a high degree of reliability and to have a long life, and conventional ceramic materials have not been satisfactory in these respects. For example, cordierite materials have low expansion properties and may be satisfactory in terms of spall resistance, but they lack homogeneity and have not been found to be of practical use. In addition, silicon carbide materials have good thermal conductivity, but materials sintered with clay etc. are weak against hot loads.
Also, breathability has not been resolved. Especially at high temperatures, it is oxidized and a SiO 2 film is formed on the particle surface.
This gradually causes the surface of the silicon carbide grains inside to become oxidized, and the difference in stress between the surface and the inside of the molded product gradually increases, eventually leading to breakage, which is a state in which it is no longer able to fully demonstrate its properties. It was hot. In order to make full use of the characteristics of the heat-resistant material base material, the present invention has developed a heat exchanger that has not been seen before by improving the characteristics of the heat-resistant material base material. ) Purity 99.95 by method
% or more and a silicon carbide coating with an Fe content of 50 PPM or less is formed. That is, the presence of pores in ceramic heat-resistant materials cannot be ignored, and therefore, non-oxide materials such as silicon carbide, carbon, and silicon nitride are susceptible to oxidation at high temperatures. Therefore, the present invention attempts to suppress the penetration of oxygen into the interior by forming a highly pure, high-density silicon carbide film on the surface of a heat-resistant material. In this case, the effect cannot be expected if the coating is easily oxidized and peeled off, so in order to satisfy this requirement, it must be made dense with a purity of 99.95% or more using the CVD (chemical vapor deposition) method. , SiO2 formed when this is oxidized from the surface
The content of Fe, which is particularly susceptible to deterioration, is limited to 50 PPM or less because it is easily altered by the presence of impurities, disrupting the stress balance and causing cracks. The present invention was achieved by considering the difference in thermal expansion between the base material and the coating, stability, etc., and finding that there is a close relationship between the purity of the coating and the oxidation speed. This provides a long-life heat exchanger that is not found in ceramic materials. The heat-resistant material that should be the base material is preferably one that has a stronger bonding force with the dense silicon carbide of the coating, so silicon carbide is most suitable, and among them, 6.5 to 35% by weight of metallic silicon in the pores of silicon carbide is preferable. Silicon carbide is impregnated with bulk density 3.05 by self-sintering method.
g/cc or more, or silicon carbide mixed with silicon nitride or contained as a binder, etc. are preferable. In addition, if the silicon carbide coating itself has many pores, oxidation resistance cannot be expected.
It is necessary to take care in the CVD process so that the porosity is 1.5% or less. Examples of the present invention will be described below. Content percentage of metallic silicon as a component for heat exchangers
A 10% by weight recrystallized silicon carbide body was prepared. this
CH 3 SiCl 3 gas10c.c./min H 2 gas carrier gas
A silicon carbide film was formed at 1300°C under a reduced pressure of 20 Torr. As shown in the table, the Fe content and porosity in the coating were varied. This was processed by bonding and other processes to assemble a double tube heat exchanger and its evaluation was performed. The results are shown in the table. The evaluation was based on the number of days until cracks occurred in the film when air at room temperature was heated by dry air with an inlet temperature of 1200°C. At the same time, self-sintered silicon carbide (bulk density 3.10
g/cc), recrystallized silicon carbide (porosity 20%), silicon nitride bonded silicon carbide (silicon nitride 30%), and similarly CVD treated to form a silicon carbide film containing 30 PPM Fe (porosity 1%). The following) were formed and the lifespan was measured.
The results are shown in a table.
【表】
表から明らかなようにCVD膜を形成しなかつ
たものが最も寿命が短く、Fe80PPMのもの、或
いは膜の気孔率1.6％のものも他の条件のものに
比較して相対的に短い寿命であつた。多孔質再結
晶炭化珪素体にSiを6.5〜35重量％含浸させるこ
とはガス不透過性にするために必要なことであ
り、この範囲を逸脱するとガスリークが生ずるば
かりでなく強度が低下し好ましくない。又、自焼
結炭化珪素体はＢ等の焼結助剤を極微量添加して
炭化珪素のみを焼結するものであり、嵩比重3.05
ｇ／c.c.以下のものでは強度が低下し、更に特性に
バラツキが生ずるようになる。炭化珪素は結合剤
として金属シリコンを使用してこれを窒素ガス雰
囲気中で焼成することによつて窒化珪素に転化さ
せ、この生成窒化珪素によつて結合強度を発現さ
せる材料も本発明に適用することが可能である。
しかしながらその範囲は窒化珪素が65重量％迄
で、これ以上では熱膨脹が小さくなり炭化珪素被
膜のそれとズレが生ずるようになり、クラツクが
発生しやすくなる。
本発明によつて期待できる効果は単純な形状で
ある二重管式のみならず、一般に知られている多
管式のものでもよく、又、自動車のガスタービン
エンジンの蓄熱式、伝熱式の形式にとわれること
なく応用が可能であり、更に熱交換器全部に適用
する場合だけでなく、必要最少限の部分のみに適
用することも可能である。[Table] As is clear from the table, the lifespan is the shortest for those that do not form a CVD film, and the lifespan for Fe80PPM or films with a porosity of 1.6% is also relatively short compared to those under other conditions. It was at the end of its lifespan. It is necessary to impregnate the porous recrystallized silicon carbide body with 6.5 to 35% by weight of Si in order to make it gas impermeable, and deviation from this range is not preferable because it not only causes gas leaks but also reduces strength. . In addition, the self-sintering silicon carbide body is made by adding a very small amount of sintering aid such as B to sinter only silicon carbide, and has a bulk specific gravity of 3.05.
If it is less than g/cc, the strength will decrease and further variations will occur in the properties. Silicon carbide is a material that uses metallic silicon as a binder and is converted into silicon nitride by firing it in a nitrogen gas atmosphere, and that develops bonding strength by the generated silicon nitride. Is possible.
However, the range is up to 65% by weight of silicon nitride, and if it exceeds this, the thermal expansion will become small and misalignment with that of the silicon carbide film will occur, making cracks more likely to occur. The effects that can be expected from the present invention are not limited to the simple double-tube type, but also to the generally known multi-tube type, as well as the heat storage type and heat transfer type of automobile gas turbine engines. It can be applied to any type of heat exchanger, and can be applied not only to the entire heat exchanger, but also to only the minimum necessary portion.
Claims (1)
熱する方式の熱交換器において、該隔壁の少なく
とも一部が純度99.95％以上でかつFe含有量
50PPM以下のCVD法により形成させた炭化珪素
によつて被覆された耐熱性材料から成つているこ
とを特徴とする炭化珪素質熱交換器。 ２ 被覆された炭化珪素の気孔率が1.5％以下で
あることを特徴とする特許請求の範囲第１項記載
の熱交換器。 ３ 耐熱性材料が炭化珪素質であることを特徴と
する特許請求の範囲第１項または第２項記載の熱
交換器。 ４ 耐熱性材料が金属シリコンを6.5〜35重量％
含むことを特徴とする特許請求の範囲第３項記載
の熱交換器。 ５ 耐熱性材料が嵩密度3.05ｇ／c.c.以上の炭化珪
素焼結体からなることを特徴とする特許請求の範
囲第３項記載の熱交換器。 ６ 耐熱性材料が気孔率９〜35％の炭化珪素成形
体からなることを特徴とする特許請求の範囲第３
項記載の熱交換器。 ７ 耐熱性材料が65重量％までの窒化珪素を含む
ことを特徴とする特許請求の範囲第３項記載の熱
交換器。[Scope of Claims] 1. A heat exchanger that heats a low-temperature fluid with a high-temperature fluid through a partition wall, in which at least a portion of the partition wall has a purity of 99.95% or more and contains Fe.
1. A silicon carbide heat exchanger, characterized in that it is made of a heat-resistant material coated with silicon carbide formed by a CVD method of 50 PPM or less. 2. The heat exchanger according to claim 1, wherein the coated silicon carbide has a porosity of 1.5% or less. 3. The heat exchanger according to claim 1 or 2, wherein the heat-resistant material is silicon carbide. 4 Heat-resistant material contains 6.5 to 35% by weight of metallic silicon
A heat exchanger according to claim 3, characterized in that the heat exchanger comprises: 5. The heat exchanger according to claim 3, wherein the heat-resistant material is made of a silicon carbide sintered body having a bulk density of 3.05 g/cc or more. 6 Claim 3, wherein the heat-resistant material is made of a silicon carbide molded body with a porosity of 9 to 35%.
Heat exchanger as described in section. 7. Heat exchanger according to claim 3, characterized in that the heat-resistant material contains up to 65% by weight of silicon nitride.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15776582A JPS5946494A (en) | 1982-09-10 | 1982-09-10 | Heat exchanger of silicon carbide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15776582A JPS5946494A (en) | 1982-09-10 | 1982-09-10 | Heat exchanger of silicon carbide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5946494A JPS5946494A (en) | 1984-03-15 |
| JPH027000B2 true JPH027000B2 (en) | 1990-02-14 |
Family
ID=15656819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15776582A Granted JPS5946494A (en) | 1982-09-10 | 1982-09-10 | Heat exchanger of silicon carbide |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5946494A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100877574B1 (en) * | 2006-12-08 | 2009-01-08 | 한국원자력연구원 | High temperature, high pressure and corrosion resistant process heat exchangers for nuclear hydrogen production |
| JP2009019786A (en) * | 2007-07-10 | 2009-01-29 | Kobe Steel Ltd | Exhaust gas treatment apparatus and method for rotary hearth type reduction furnace |
| JP5819838B2 (en) * | 2010-09-29 | 2015-11-24 | 日本碍子株式会社 | Heat exchange member |
-
1982
- 1982-09-10 JP JP15776582A patent/JPS5946494A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5946494A (en) | 1984-03-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3548914B2 (en) | Method for producing catalyst carrier | |
| JPS6047225B2 (en) | Manufacturing method for densified silicon products | |
| US5300322A (en) | Molybdenum enhanced low-temperature deposition of crystalline silicon nitride | |
| JP3296495B2 (en) | Hydrogen torch | |
| JPH027000B2 (en) | ||
| JPH0624636B2 (en) | Catalyst carrier and method for producing the same | |
| JP4299155B2 (en) | Oxidation-resistant coating method for carbon / carbon composite materials | |
| US6007883A (en) | Hydrogen torch | |
| US4107392A (en) | High temperature abrasion-resistant material and method of producing same | |
| JPWO2015025951A1 (en) | Porous ceramics and method for producing the same | |
| US4485143A (en) | Silicon carbide material for low-melting point fusion metal | |
| JPH026999B2 (en) | ||
| JPH026998B2 (en) | ||
| JP2000351679A (en) | Method for producing porous silicon carbide body and porous silicon carbide body | |
| EP1452488A1 (en) | Method of producing silicon carbide ceramics from plant precursors | |
| JPH01258715A (en) | Silicon carbide honeycomb filter and its production | |
| JPH03221442A (en) | Corrosion resistant oxidation resistant material | |
| US3956193A (en) | Conductivity of silicon nitride | |
| US20250243952A1 (en) | Tubing for high-temperature systems | |
| JP3108362B2 (en) | High-strength inorganic fiber molded body | |
| JPS6046980A (en) | Inorganic porous body structure | |
| JPS60118685A (en) | Manufacture of silicon nitride-coated graphitic refractories | |
| JPH0776131B2 (en) | Silicon nitride sintered member | |
| JPS6360000B2 (en) | ||
| JPS583999B2 (en) | Method for manufacturing composite material consisting of ceramics and metal |