JPS62241873A - Immersion protective pipe for molten metal - Google Patents
Immersion protective pipe for molten metalInfo
- Publication number
- JPS62241873A JPS62241873A JP61084382A JP8438286A JPS62241873A JP S62241873 A JPS62241873 A JP S62241873A JP 61084382 A JP61084382 A JP 61084382A JP 8438286 A JP8438286 A JP 8438286A JP S62241873 A JPS62241873 A JP S62241873A
- Authority
- JP
- Japan
- Prior art keywords
- molten metal
- silicon carbide
- silicon
- immersion
- protective pipe
- 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
- 229910052751 metal Inorganic materials 0.000 title claims description 14
- 239000002184 metal Substances 0.000 title claims description 14
- 238000007654 immersion Methods 0.000 title claims description 9
- 230000001681 protective effect Effects 0.000 title description 13
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 26
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 26
- 238000002844 melting Methods 0.000 claims description 12
- 230000008018 melting Effects 0.000 claims description 11
- 238000005245 sintering Methods 0.000 claims description 11
- 210000002808 connective tissue Anatomy 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 11
- 229910052782 aluminium Inorganic materials 0.000 description 10
- 239000011148 porous material Substances 0.000 description 9
- 229910052710 silicon Inorganic materials 0.000 description 8
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 239000010703 silicon Substances 0.000 description 7
- 239000011247 coating layer Substances 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 6
- 238000005260 corrosion Methods 0.000 description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 229910018540 Si C Inorganic materials 0.000 description 2
- 229910052581 Si3N4 Inorganic materials 0.000 description 2
- 238000009529 body temperature measurement Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910052814 silicon oxide Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 241000257465 Echinoidea Species 0.000 description 1
- 101710096655 Probable acetoacetate decarboxylase 1 Proteins 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000002612 dispersion medium Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000004447 silicone coating Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
Landscapes
- Measuring Temperature Or Quantity Of Heat (AREA)
- Ceramic Products (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
- Furnace Details (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
産業上の１
この発明は、アルミニウム（ＡＱ）、鉛（Ｐｂ ）等の
溶融金属を溶解または保持するための炉に浸漬して使用
ずる浸漬ヒータ保護管や測温用保護管等の保護管に関す
るものである。[Detailed Description of the Invention] Industrial 1 This invention relates to an immersion heater protection tube that is used by being immersed in a furnace for melting or holding molten metals such as aluminum (AQ) and lead (Pb), and for temperature measurement. This relates to protection tubes such as protection tubes.
従」ヒ久弦」Ｌ
従来、この種の保護管をアルミニウム溶解保持炉に使用
して、たとえばヒータ、測温用熱電対、ガス吹込み管等
を溶湯中に浸漬していた。Conventionally, this type of protection tube was used in an aluminum melting and holding furnace to immerse, for example, a heater, a thermocouple for temperature measurement, a gas injection pipe, etc. into the molten metal.
近年、これらの保護管として、鋳鉄製に代わって炭化珪
素質のものが使用ざれるようになってきた。炭化珪素成
形体の気孔に金属珪素を含浸させたものや、あるいは再
結晶炭化珪素体表面にコーテング層を設けたもの等が提
案されている。In recent years, silicon carbide protective tubes have been used instead of cast iron for these protective tubes. It has been proposed that the pores of a silicon carbide molded body are impregnated with metallic silicon, or that a coating layer is provided on the surface of a recrystallized silicon carbide body.
蒐 ゛しよーと゜る１】、、
従来の炭化珪ｊＩ質保護管は、いずれも溶解アルミニウ
ムによって浸蝕され、長時間の使用に耐えることがでぎ
なかった。All conventional silicon carbide protection tubes were corroded by molten aluminum and could not withstand long-term use.
炭化珪素成形体は珪化体であっても１５・〜３０％の気
孔を右し、製造条件にＪ二っで気孔率が大きく変動する
ため、各種の気孔率をしったものが存在するが、いずれ
にしても炭化珪素成形体の気孔に溶融アルミニウムが入
り易く、そのため、これがマイク［１クラツクの発生や
溶損等の原因となっていた。Even if a silicon carbide molded body is a silicided body, it has 15% to 30% of porosity, and the porosity varies greatly depending on the manufacturing conditions, so there are products with various porosity, but However, molten aluminum easily enters the pores of the silicon carbide molded body, which causes microphone cracks and melting damage.
このような気孔を減少させるために前述のように成形体
の気孔をシリコンで埋めることら試みられたが、その場
合は、溶融アルミニウムがシリコンと合金化し、低融点
物質を生成するため、製品の長寿命化にはつながらなか
った。In order to reduce these pores, attempts have been made to fill the pores in the molded body with silicon as described above, but in that case, the molten aluminum alloys with silicon and produces a low melting point substance, which causes problems in the product. It did not lead to a longer lifespan.
また、炭化珪素体の表面にコーテングを施して表面の気
孔をこれらのコーテング材で充填したものも提案された
が、コーテング材と炭化珪素基材との熱膨張差等によっ
て容易にコーテング層が剥落してしまう欠点があった。Also, it has been proposed that the surface of the silicon carbide body is coated and the pores on the surface are filled with these coating materials, but the coating layer easily peels off due to the difference in thermal expansion between the coating material and the silicon carbide base material. There was a drawback to it.
また、コーテング層が溶融アルミニウムと反応して脱落
してしまい、コーテング層の本来の機能が満足できる程
度に発揮されなかった。Further, the coating layer reacted with molten aluminum and fell off, so that the original function of the coating layer could not be exhibited to a satisfactory degree.
また、炭化珪素成形体はその製造上の特質から″ｆ１ｔ
１１珪素あるいは酸化珪素が残存しや１く、場合によっ
ては残存率がＳｉ ０２ ＋Ｓｉとして１５％にものぼ
ることがある。このＪ：うに遊離珪素あるいは酸化珪素
が多量に存在すると、浸蝕や剥離、反応等を受けやすい
という問題があった。In addition, due to its manufacturing characteristics, silicon carbide molded bodies are
11 silicon or silicon oxide is unlikely to remain, and in some cases the residual rate may reach as high as 15% as Si 02 +Si. When a large amount of free silicon or silicon oxide is present in this J: sea urchin, there is a problem that it is susceptible to corrosion, peeling, reaction, etc.
ＩＬ！ＬＩＬ左
この発明は前述のような従来技術の諸欠点を解消して、
耐用寿命を長くすることのできる溶融金属用浸漬保護管
を提供することを目的としている。IL! This invention solves the drawbacks of the prior art as mentioned above,
The object is to provide a molten metal immersion protection tube that can have a long service life.
１１悲１１
前述の目的を達成するために、この発明は低融点金属を
溶解または保持するための炉に用いる保護管において、
炭化珪素および八９．２０３から成る焼結助剤による結
合組織を有することを特徴とする溶融金属用浸漬保護管
を要旨としている。11 Tragedy 11 In order to achieve the above object, the present invention provides a protective tube for use in a furnace for melting or holding low melting point metals,
The gist of this invention is an immersion protection tube for molten metal characterized by having a connective structure made of silicon carbide and a sintering aid made of 89.203.
、 Ｊを °ａするた の−
この発明ににる溶融金属用浸漬保護管においては、炭化
珪素およびＡ ＋１２０３から成る焼結助剤による結合
組織を有する。Ａ Ｑｚ Ｏ３は好ましくは５〜２０％
である。The immersion protection tube for molten metal according to the present invention has a connective tissue formed by a sintering aid made of silicon carbide and A+1203. A Qz O3 is preferably 5-20%
It is.
このように炭化珪素およびＡ Ｑ２０３から成る焼結助
剤による結合組織にするための理由を説明する。The reason for creating a connective structure using the sintering aid made of silicon carbide and AQ203 will be explained.
従来技術の問題点は要するに炭化珪素成形体の気孔が１
５〜３０％も存在するため、それらの気孔に溶融金属が
入りや１°く、クラックや溶損等の原因となっていたと
ころにある。The problem with the conventional technology is that the silicon carbide molded body has only 1 pore.
Since 5 to 30% of the molten metal is present, the molten metal easily enters the pores, causing cracks and melting damage.
このような気孔を金属シリコンヤ）コーテング等により
埋めていたが、溶融アルミニウムとシリコンが合金化し
、低融点物質を生成したり、熱膨張差によりコーティン
グ層が剥離したりして、長寿命化が実現できなかった。These pores were filled with metal silicone coatings, etc., but molten aluminum and silicon alloyed to form a low melting point substance, and the coating layer peeled off due to the difference in thermal expansion, resulting in a longer life. could not.
この発明はこのような実情に鑑みて成されたものであり
、炭化珪素にＡ Ｑ２０３から成る焼結助剤を加えて緻
密な炭化珪素質いわゆる自焼結炭化珪素体とし、それを
溶融金属の溶解あるいは保持のための炉に用いる各種保
護管に適用したものである。This invention was made in view of the above circumstances, and is made by adding a sintering aid consisting of AQ203 to silicon carbide to make a dense silicon carbide material, so-called self-sintering silicon carbide body, and then converting it into a molten metal. It is applied to various protective tubes used in furnaces for melting or holding.
この種の保護管を炭化珪素およびＡ Ｑ２０３から成る
焼結助剤による自焼結体とすることにより、緻密な結合
組織が得られ、見掛は気孔率を１％程度におさえること
ができ、従来のように３ｉを含浸したり、コーテング層
を設けなくても、炭化珪素質保護管の耐熱性や耐蝕性等
の特性を大幅に向上することができる。By making this type of protective tube a self-sintered body using a sintering aid made of silicon carbide and AQ203, a dense connective structure can be obtained, and the apparent porosity can be suppressed to about 1%. The heat resistance, corrosion resistance, and other characteristics of the silicon carbide protection tube can be greatly improved without impregnating it with 3i or providing a coating layer as in the conventional case.
また、保護管を自焼結体とすることにより、浸蝕や剥離
等を受けやすい５ｉＯｚと３＋の介在しない結合組織を
得ることができる。Furthermore, by making the protective tube a self-sintered body, a connective tissue free of 5iOz and 3+, which are susceptible to corrosion and peeling, can be obtained.
このようにして、この発明に３１；る溶融全屈用浸漬保
護管は従来技術に比較して非常に長寿命としうるしので
ある。In this way, the melting full-bending immersion protective tube according to the present invention can have a much longer lifespan than those of the prior art.
Ａ Ｑ２０３を５〜２０％にする理由について説明する
と、Ａ Ｑ２０ ：ｓが５％Ｊ：りも小さいと、焼結助
剤としての効果が小さく、焼結が十分進行せず緻密性に
劣る。逆にＡ ＋１２０３が２０％よりも大であると、
高温における強度の劣化、もしくは熱衝撃抵抗性が極度
に低下する。The reason for setting AQ203 to 5 to 20% is as follows: If AQ20:s is smaller than 5%J:, the effect as a sintering aid is small, sintering does not proceed sufficiently, and the density is poor. Conversely, if A +1203 is greater than 20%,
Deterioration of strength or extremely low thermal shock resistance at high temperatures.
支ＬＬ
比表面積１５ｍ２／ｇの焼結用ＳｉＣ微粉８ｓ Ｉ ｍ
ａｎと、焼結助剤としてＡ１１２０３１２重量部を混
合し、水を分散媒としてスリップを製造した。このよう
なスリップに解Ｆ！踊としてＮａ ２ Ｓｉ ０３を外
重量部で０．３％だけ混合した。このような混合物を成
型して脱型したのち、２２３０℃の不活性雰囲気下で焼
結した。それにより密度３．１＝１の焼結体を得た。そ
の焼結体の寸法は外径５５ｍｍ、内径５Ｑｍｍ、長さ５
ＱＱｍｍであった。Support LL SiC fine powder for sintering with a specific surface area of 15 m2/g 8s I m
An and 312 parts by weight of A1120312 as a sintering aid were mixed, and a slip was manufactured using water as a dispersion medium. The solution to such slips is F! As a substitute, Na 2 Si 03 was mixed in an amount of 0.3% by weight. After molding and demolding such a mixture, it was sintered at 2230° C. in an inert atmosphere. As a result, a sintered body with a density of 3.1=1 was obtained. The dimensions of the sintered body are outer diameter 55mm, inner diameter 5Qmm, and length 5.
It was QQmm.
この焼結体の機械的強度は３００ＭＰａであった。また
、本発明による保護管と比較するために、従来より浸漬
ヒータ用保護管として広く使用されているＳｔ ３ Ｎ
４ ＢｏｎｄｅｄＳｉＣおよび再結晶質ＳｉＣの保護管
を使用して、寿命試験を行った。これらの耐用日数は表
１に示すと−３つである。表１に示した耐用日数はアル
ミニウムが炉の内壁に侵入してくるまでの日数である。The mechanical strength of this sintered body was 300 MPa. In addition, in order to compare with the protection tube according to the present invention, St 3 N, which has been widely used as a protection tube for immersion heaters, was used.
4 Life tests were conducted using Bonded SiC and recrystallized SiC protection tubes. Their service life is -3 as shown in Table 1. The service life shown in Table 1 is the number of days until aluminum invades the inner wall of the furnace.
しかも、表１に示す数字は、それぞれ５本の保護管を使
って実験した時の平均耐用日数である。Moreover, the numbers shown in Table 1 are the average service life when an experiment was conducted using five protection tubes.
なお、寿命試験の条件についていえば、アルミニウムの
温度を７００℃とし、アルミニウムの種類はＡＤＣ−１
２（アルミニウム８９％とシリコン１１％）であり、保
護管の内部にＳｉＣヒータを配置した。Regarding the conditions of the life test, the temperature of the aluminum was 700℃, and the type of aluminum was ADC-1.
2 (89% aluminum and 11% silicon), and a SiC heater was placed inside the protective tube.
表１から明らかなＪ：うに、この発明による保護管は従
来品に比較して非常に優れた耐蝕効果を奏した。It is clear from Table 1 that the protective tube according to the present invention exhibited an extremely superior corrosion resistance effect compared to conventional products.
また、ＳｉＣ質の基材に対するＡｌｌの浸蝕は次のよう
なメカニズムで進行することが確認された。つまり、Ｓ
ｉＣもしくはＳｉ３Ｎ４は８００℃程度から酸化現象が
発生し、次のような反応が生じる。Further, it was confirmed that the corrosion of All on the SiC base material progresses by the following mechanism. In other words, S
An oxidation phenomenon occurs in iC or Si3N4 at about 800° C., and the following reaction occurs.
Ｓｉ Ｃ＋２０２→Ｓｉ ０２ ＋ＣＯ２Ｓｉ ３ Ｎ
４ ＋３０２→３Ｓｉ ０２ ＋２Ｎ２このようにＳｉ
ＣもしくはＳｉ ３ Ｎ４白休はΔｑに対して耐蝕性も
悪く、濡れ特性も優れている。しかしながら、それらの
表面に生成したＳｉＯ２はＡＱに対し非常に活性である
ことが確認された。つまり、次の反応が急速に進行する
ことが判明したのである。Si C+202→Si 02 +CO2Si 3 N
4 +302→3Si 02 +2N2 Like this Si
C or Si 3 N4 has poor corrosion resistance and excellent wetting properties with respect to Δq. However, it was confirmed that the SiO2 generated on their surfaces is very active against AQ. In other words, it was found that the following reaction proceeded rapidly.
４ＡＱ ＋３Ｓｉ ０２→２Ａ（１２０３＋３ｓｉした
がって、保護管の耐用日数は保護管の基材の耐酸化性に
依存するという事実が明らかとなったのである。4AQ +3Si 02→2A (1203+3si) Therefore, it has become clear that the service life of the protective tube depends on the oxidation resistance of the base material of the protective tube.
なお、この発明による保護管は密度が高く、内部の比表
面積が極度に小さく（つまり閉じた気孔が多い）、耐酸
化特性が優れているため、前述のように低融点金属保持
炉用の浸漬ヒータ保護管として最適のものである。The protective tube according to the present invention has a high density, has an extremely small internal specific surface area (that is, has many closed pores), and has excellent oxidation resistance. It is ideal as a heater protection tube.
代理人 弁理士 田辺 徹 ′、 ｌ：・１１ パ、、、、／ 表 材質 Ｓｉ ３ Ｎ４結合ＳｉＣ 再結晶質ＳｉＣ 本発明（ＡＱ２ｇ３） ｎ −５の平均耐用 （Ａｌｔが内壁まで侵 耐用日数 日数 入してくる口数）Agent: Patent Attorney Toru Tanabe l:・11 Pa,,,,/ table Material Si3N4 bonded SiC Recrystallized SiC The present invention (AQ2g3) Average service life of n-5 (Alt invades the inner wall) Service life number of days number of incoming units)
Claims (2)
る保護管において、炭化珪素およびＡｌ＿２Ｏ＿３から
成る焼結助剤による結合組織を有することを特徴とする
溶融金属用浸漬保護管。(1) A immersion protection tube for molten metal, which is used in a furnace for melting or holding a low-melting metal, and is characterized by having a connective tissue formed by a sintering aid consisting of silicon carbide and Al_2O_3.
の範囲１項に記載された溶融金属用浸 漬保護管。(2) The immersion protection tube for molten metal according to claim 1, wherein Al_2O_3 is 5 to 20% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61084382A JPS62241873A (en) | 1986-04-14 | 1986-04-14 | Immersion protective pipe for molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61084382A JPS62241873A (en) | 1986-04-14 | 1986-04-14 | Immersion protective pipe for molten metal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62241873A true JPS62241873A (en) | 1987-10-22 |
Family
ID=13829001
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61084382A Pending JPS62241873A (en) | 1986-04-14 | 1986-04-14 | Immersion protective pipe for molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62241873A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015093814A (en) * | 2013-11-13 | 2015-05-18 | コバレントマテリアル株式会社 | Protective tube material for metal melting furnace, protective tube for metal melting furnace and manufacturing method therefor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5696779A (en) * | 1979-12-28 | 1981-08-05 | Toshiba Ceramics Co | Member for low melting point metal melt keeping furnace |
| JPS5742577A (en) * | 1980-08-29 | 1982-03-10 | Asahi Glass Co Ltd | Silicon carbide ceramic sintered body and manufacture |
-
1986
- 1986-04-14 JP JP61084382A patent/JPS62241873A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5696779A (en) * | 1979-12-28 | 1981-08-05 | Toshiba Ceramics Co | Member for low melting point metal melt keeping furnace |
| JPS5742577A (en) * | 1980-08-29 | 1982-03-10 | Asahi Glass Co Ltd | Silicon carbide ceramic sintered body and manufacture |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2015093814A (en) * | 2013-11-13 | 2015-05-18 | コバレントマテリアル株式会社 | Protective tube material for metal melting furnace, protective tube for metal melting furnace and manufacturing method therefor |
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