JPH03232762A - Magnesia-containig refractory - Google Patents
Magnesia-containig refractoryInfo
- Publication number
- JPH03232762A JPH03232762A JP2028436A JP2843690A JPH03232762A JP H03232762 A JPH03232762 A JP H03232762A JP 2028436 A JP2028436 A JP 2028436A JP 2843690 A JP2843690 A JP 2843690A JP H03232762 A JPH03232762 A JP H03232762A
- Authority
- JP
- Japan
- Prior art keywords
- magnesia
- refractory
- zircon
- slag
- fired
- 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
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 85
- 239000000395 magnesium oxide Substances 0.000 claims abstract description 42
- 229910052845 zircon Inorganic materials 0.000 claims abstract description 23
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 claims abstract description 23
- 239000002245 particle Substances 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 7
- 238000000465 moulding Methods 0.000 claims abstract description 6
- 238000010304 firing Methods 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 2
- 239000011230 binding agent Substances 0.000 abstract description 2
- 239000012535 impurity Substances 0.000 abstract description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N ZrO2 Inorganic materials O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 18
- 239000002893 slag Substances 0.000 description 14
- 239000011819 refractory material Substances 0.000 description 11
- 238000000034 method Methods 0.000 description 7
- 230000007797 corrosion Effects 0.000 description 6
- 238000005260 corrosion Methods 0.000 description 6
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 230000003628 erosive effect Effects 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 229910052839 forsterite Inorganic materials 0.000 description 4
- HCWCAKKEBCNQJP-UHFFFAOYSA-N magnesium orthosilicate Chemical compound [Mg+2].[Mg+2].[O-][Si]([O-])([O-])[O-] HCWCAKKEBCNQJP-UHFFFAOYSA-N 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 239000011449 brick Substances 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000011451 fired brick Substances 0.000 description 3
- 230000008595 infiltration Effects 0.000 description 3
- 238000001764 infiltration Methods 0.000 description 3
- 239000013535 sea water Substances 0.000 description 3
- 238000005245 sintering Methods 0.000 description 3
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000000292 calcium oxide Substances 0.000 description 2
- 235000012255 calcium oxide Nutrition 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000010459 dolomite Substances 0.000 description 2
- 229910000514 dolomite Inorganic materials 0.000 description 2
- 238000005187 foaming Methods 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 229910052596 spinel Inorganic materials 0.000 description 2
- 239000011029 spinel Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 235000014380 magnesium carbonate Nutrition 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000011823 monolithic refractory Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Compositions Of Oxide Ceramics (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、例えば取鍋、転炉、電気炉、真空脱ガス装置
などの特に塩基度の高いスラブの生成を伴なう溶融金属
用容器あるいは流通路の内張り耐火物として用いられる
マグネシア含有耐火物に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to vessels for molten metal with the production of slabs of particularly high basicity, such as ladles, converters, electric furnaces, vacuum degassers, etc. Or it relates to a magnesia-containing refractory used as a refractory lining for flow passages.
（従来技術）
マグネシア（ＭｇＯ）は融点が高く、高塩基度のスラグ
に対して高い耐食性を示す。このため、マグネシアをｉ
原料とした耐火物が鉄鋼製造プロセスの中で広く使用さ
れている。(Prior Art) Magnesia (MgO) has a high melting point and exhibits high corrosion resistance against highly basic slag. For this reason, magnesia is
Refractories as raw materials are widely used in the steel manufacturing process.
マグネシア質焼成耐火物に使用されるマグネシア原料と
しては、天然のマグネサイトを熱処理して焼結させた天
然マグネシア、海水から採取したマグネシアを焼結させ
た海水マグネシア、これを電気炉で一旦溶解した電融マ
グネシアなどがある。The magnesia raw materials used for magnesia-based fired refractories include natural magnesia, which is made by heat-treating and sintering natural magnesite, seawater magnesia, which is made by sintering magnesia collected from seawater, and seawater magnesia, which is melted once in an electric furnace. Examples include fused magnesia.
これらの原料を適当な粒度に調整して必要に応じて他の
耐火粒子を配合し、混線・成形・焼成することでマグネ
シア質耐火物を得ている。（参考技術特開昭６０−２５
１１６８号公報）
（発明が解決しようとする課題）
しかし、マグネシアを含有する焼成耐火物にはスラグが
侵入しやすく、これが原因となって耐火物の溶損、剥離
が進行しやすい。従来、スラグの侵入を押えるために、
粒度構成やプレス成形圧力などを改善することで耐火物
のｌｌｌ１密化が試みられている。しかし、スラグの侵
入がマグネシア含有焼成耐火物の損耗に与える影響は依
然として大きい。Magnesia-based refractories are obtained by adjusting these raw materials to appropriate particle sizes, blending other refractory particles as necessary, and cross-wiring, molding, and firing. (Reference technology JP-A-60-25
(Publication No. 1168) (Problems to be Solved by the Invention) However, slag easily enters the fired refractory containing magnesia, and this tends to cause the refractory to melt and peel. Conventionally, in order to prevent slag from entering,
Attempts have been made to increase the density of refractories by improving the particle size structure, press molding pressure, etc. However, the influence of slag penetration on the wear and tear of magnesia-containing fired refractories is still large.
マグネシアを含有する焼成耐火物へのスラグの侵入を抑
制するためには、耐火物を緻密化する方法と、マグネシ
ア粒界部分にスラグの侵入を食い止める物質を入れてお
く方法がある。緻密化は、前述の通り従来から試みられ
ているが、まだ充分といえるところまでは成功していな
い。スラグの侵入を食い止める物質としてはまず考えら
れるのが、スラグに濡れにくい黒鉛や、炭化物、硼化物
。In order to suppress the intrusion of slag into fired refractories containing magnesia, there are two methods: densifying the refractory and adding a substance to the magnesia grain boundaries to prevent slag from entering. As mentioned above, attempts have been made to achieve densification, but they have not yet succeeded to a sufficient degree. The first substances that can be considered to prevent slag from entering are graphite, carbides, and borides, which are difficult to get wet with slag.
窒化物などがある。これらの物質はスラグと濡れ難いた
めスラグをはじき、その侵入を食い止める。There are nitrides, etc. These substances are difficult to wet with slag, so they repel slag and prevent its intrusion.
しかし、これらの物質はいずれも焼成工程あるいは使用
中に酸化しやすく、製造あるいは使用上での困難があり
、実用域に至っていない。However, all of these materials are easily oxidized during the firing process or during use, and are difficult to manufacture or use, so they have not been put into practical use.
スラグ侵入を抑制する効果のある物質として他に考えら
れるのは、侵入スラグの粘性を上昇させてスラブの流動
性を低下させ、侵入の進展を抑制する物質である。この
種の効果を発揮するものとしては、Ｃｒ２Ｏ３，ＺｒＯ
２などがあげられる。Ｃｒ２Ｏ３に関しては、マグクロ
煉瓦の形で実用化されている。Another possible substance that is effective in suppressing slag intrusion is a substance that increases the viscosity of the invading slag and reduces the fluidity of the slab, thereby suppressing the progress of intrusion. Examples of substances that exhibit this type of effect are Cr2O3, ZrO
2 etc. can be mentioned. Regarding Cr2O3, it has been put to practical use in the form of maguro bricks.
しかし、Ｃｒ２Ｏ３がスラグの主成分の一つであるＣａ
Ｏと反応しやすい性質があるため、耐食性に限界がある
。これに対してＺｒ０２（ジルコニア）は耐食性に優れ
ており、有望である。しかし、マグネシアとジルコニア
は両方とも融点が高く、焼成工程で焼結が進行しないた
め、耐火物は緻密化しに＜＜。However, Cr2O3 is one of the main components of slag.
Since it has the property of easily reacting with O, there is a limit to its corrosion resistance. On the other hand, Zr02 (zirconia) has excellent corrosion resistance and is promising. However, magnesia and zirconia both have high melting points, and sintering does not proceed during the firing process, so the refractory does not become densified.
この点でスラブ侵入に対して不利である。また、ジルコ
ニアは比較的高価であるため、これを耐火物に混合する
と耐火物の価格が上昇し、経済的に不利である。In this respect, it is disadvantageous against slab penetration. Furthermore, since zirconia is relatively expensive, mixing it with refractories increases the price of the refractories, which is economically disadvantageous.
本発明は、これらの問題を解決すべく研究を重ねた結果
、緻密なマグネシア−ジルコニア質焼成耐火物を、価格
の上昇をあまり伴なうことなく得ることができる方法を
提供するものである。As a result of repeated research aimed at solving these problems, the present invention provides a method for obtaining a dense magnesia-zirconia fired refractory without significantly increasing the price.
（課題を解決するための手段）
本発明の第１の発明は、マグネシアとジルコンを混合、
成型して焼成したことを特徴とするマグネシア含有耐火
物であり、又第２の発明は、この第１の発明のマグネシ
ア含有物耐火物と他の耐火粒子を混合、成型して焼成し
たことを特徴とする。(Means for Solving the Problems) The first invention of the present invention is to mix magnesia and zircon,
A second invention is a magnesia-containing refractory characterized by being molded and fired, and a second invention is a magnesia-containing refractory characterized by mixing the magnesia-containing refractory of the first invention and other refractory particles, molding, and firing. Features.
マグネシア含有耐火物である。It is a refractory containing magnesia.
本発明による耐火物の焼成時の製造方法と反応過程につ
いて、マグネシアとジルコン（ＺｒＯ２・５ｉｎ２）の
混合物の場合で説明する。マグネシアとジルコンとバイ
ンダーを混練して成型し、乾燥後、焼成炉で焼成する。The manufacturing method and reaction process during firing of the refractory according to the present invention will be explained using a mixture of magnesia and zircon (ZrO2.5in2). Magnesia, zircon, and a binder are kneaded and molded, dried, and fired in a kiln.
焼成温度は１６００℃程度以上とする。焼成過程でジル
コンはジルコニア（ＺｒＯ２）とシリカ（ＳｉＯ□）に
解離し、生成したシリカはマグネシアの一部と反応し、
フォルステライト（２Ｍｇｏ−８ｉＯ□）を生成する。The firing temperature is approximately 1600°C or higher. During the firing process, zircon dissociates into zirconia (ZrO2) and silica (SiO□), and the generated silica reacts with a portion of magnesia.
Forsterite (2Mgo-8iO□) is produced.
すなわち、マグネシアとジルコンの混合物を焼成するこ
とで、マグネシアとジルコニアとフォルステライトが生
成する。これを冷却しても、マグネシアとジルコニアと
フォルステライトは安定に共存し、この鉱物組合せの焼
成煉瓦が完成する。なお、ジルコンの重量比が７０％を
超えると、全てのマグネシアが反応して消失してしまい
、フォルステライトとジルコニアとジルコンからなる焼
成体ができ、マグネシア効果が大巾に低下し、耐食性が
低下する。 このため、ジルコンの添加量は最大でも７
０重量％までとする必要があり、ジルコン添加効果を顕
著に得るためには、ジルコンの添加量は３重量％以上は
必要である。マグネシア効果を充分に確保し、ジルコン
添加効果を効果的に得るためにはジルコンの添加量は５
〜３０重量％とすることがより好ましい。That is, by firing a mixture of magnesia and zircon, magnesia, zirconia, and forsterite are generated. Even after cooling, magnesia, zirconia, and forsterite coexist stably, and a fired brick with this mineral combination is completed. If the weight ratio of zircon exceeds 70%, all the magnesia will react and disappear, creating a fired body consisting of forsterite, zirconia, and zircon, which will greatly reduce the magnesia effect and reduce corrosion resistance. do. For this reason, the amount of zircon added is at most 7
The amount of zircon needs to be up to 0% by weight, and in order to significantly obtain the effect of adding zircon, the amount of zircon added must be 3% by weight or more. In order to sufficiently secure the magnesia effect and effectively obtain the zircon addition effect, the amount of zircon added is 5.
It is more preferable to set the content to 30% by weight.
マグネシアとジルコンの混合物の前記の反応に伴って、
焼成中の煉瓦組織内に液相が生成し、粒子どうしの焼結
を助は焼成体は緻密化する。With the above reaction of the mixture of magnesia and zircon,
A liquid phase is generated within the structure of the brick during firing, which helps the particles to sinter together, making the fired body denser.
以上、マグネシアとジルコンの混合物の場合について説
明したが、これに他の耐火粒子が加わった耐火物の場合
も、同様の機構で反応が起こる。Although the case of a mixture of magnesia and zircon has been described above, a reaction occurs in a similar mechanism in the case of a refractory in which other refractory particles are added.
使用原料については、マグネシアに関しては純度９５％
程度以上、ジルコンについては不純物成分１０％程度以
下の、いずれも通常使用されている品質のもので差し支
えない。また、他の耐火粒子としては、スピネル、アル
ミナ、クロム鉱、マグクロクリンカー、カルシア、ドロ
マイトなどをあげることができる。なお、還元焼成を行
うのであれば、黒鉛、炭化物、硼化物、窒化物なども使
用可能である。これらの耐火粒子及びその配合量はスラ
グの塩基度等を考慮して適宜選定する。Regarding the raw materials used, the purity of magnesia is 95%.
For zircon, the impurity content is about 10% or less, and any quality that is commonly used may be used. In addition, other refractory particles include spinel, alumina, chromite, maguroclinker, calcia, dolomite, and the like. Note that if reduction firing is performed, graphite, carbide, boride, nitride, etc. can also be used. These refractory particles and their blending amount are appropriately selected in consideration of the basicity of the slag, etc.
ところで、単純にマグネシアとジルコンを混合した不定
形耐火物が存在するが、これを１６００℃以上の温度域
で使用すると、急激な温度上昇によってジルコンが分解
し、その際に発泡現象が起こり、耐火物組織が不安定に
なり、耐火物の強度が著しく低下する。これと比較して
本発明による耐火物の場合は、−旦温度上昇が比較的緩
らかな焼成工程を経ているため、使用中に発泡現象は生
じず、組織変化あるいは著しい強度低下も起こらず、安
定的に使用できる。By the way, there is a monolithic refractory that is simply a mixture of magnesia and zircon, but when this is used in a temperature range of 1,600°C or higher, the zircon decomposes due to the rapid temperature rise, and a foaming phenomenon occurs at that time, causing the fire resistance to deteriorate. The material structure becomes unstable and the strength of the refractory material decreases significantly. In comparison, in the case of the refractory according to the present invention, the temperature rise is relatively slow during the firing process, so no foaming phenomenon occurs during use, and no structural change or significant decrease in strength occurs. Can be used stably.
（実施例）
マグネシア、ジルコン、スピネル、クロム鉱、マグクロ
クリンカー、カルシア、ドロマイトなどを第１表のよう
に配合して混合、焼成して焼成煉瓦を試作した。第１表
にこの焼成煉瓦の性質を示す。(Example) Magnesia, zircon, spinel, chromite, maguro clinker, calcia, dolomite, etc. were blended as shown in Table 1, mixed, and fired to make a trial fired brick. Table 1 shows the properties of this fired brick.
本侵食試験後、各試料の最大溶損部の減寸量を測定し、
比較品である試料８（通常のマグネシア煉瓦）の減寸量
を１００として基準化した。溶損指数が少ない方が耐食
性が高いことを示す。After the main erosion test, the amount of reduction in the maximum erosion area of each sample was measured,
The reduction in size of Sample 8 (ordinary magnesia brick), which is a comparative product, was standardized as 100. A lower corrosion index indicates higher corrosion resistance.
水車各試料の最大溶損部分でスラブ浸潤深さ（変質層の
厚さ）を測定し、溶損指数の場合と同様に比較品である
試料８の浸潤深さを１００として基準化した。The slab infiltration depth (thickness of the altered layer) was measured at the maximum erosion damage part of each sample of the water turbine, and as in the case of the erosion index, the infiltration depth of sample 8, which is a comparative product, was standardized as 100.
侵食試験実験条件
方 法 誘導炉による内張侵食試験
温度 １６００℃
時 間 ２時間
スラグ Ｃ／Ｓ：１．５ Ａ Ｄ、 ２０３＝］５％
５００ｇ Ｘ ４回鋼 ＳＳ４１
本発明の実施例である試料１〜７の焼成煉瓦の耐食性は
比較例である試料９〜１３の耐火物に比し１０〜２０％
程度改善されている。また、スラブ浸潤指数に関しても
１５％程度改善されている。Erosion test experimental conditions Method: Lining erosion test using induction furnace Temperature: 1600°C Time: 2 hours Slag C/S: 1.5 A D, 203=]5%
500g
It has been improved to some extent. Furthermore, the slab infiltration index was also improved by about 15%.
（発明の効果）
本発明は耐火物価格をほとんど上昇させることなく、
また耐火物製造プロセスの変更も殆どなしにマグネシア
含有焼成耐火物の耐用性を大きく改善することができる
。(Effects of the Invention) The present invention can greatly improve the durability of magnesia-containing fired refractories without increasing the price of refractories or changing the refractory manufacturing process.
Claims (2)
マグネシア含有耐火物(1) Magnesia-containing refractory made by mixing and molding magnesia and zircon and firing
て焼成したマグネシア含有耐火物(2) Magnesia-containing refractory made by mixing and molding magnesia, zircon, and refractory particles and firing the mixture
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2028436A JPH03232762A (en) | 1990-02-09 | 1990-02-09 | Magnesia-containig refractory |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2028436A JPH03232762A (en) | 1990-02-09 | 1990-02-09 | Magnesia-containig refractory |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03232762A true JPH03232762A (en) | 1991-10-16 |
Family
ID=12248619
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2028436A Pending JPH03232762A (en) | 1990-02-09 | 1990-02-09 | Magnesia-containig refractory |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03232762A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013005253A1 (en) * | 2011-07-06 | 2013-01-10 | ロザイ工業株式会社 | Magnesia-based refractory material |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5171312A (en) * | 1974-12-19 | 1976-06-21 | Tokyo Yogyo Kk | |
| JPS6011263A (en) * | 1983-06-24 | 1985-01-21 | 黒崎窯業株式会社 | Low heat conductivity basic refractories |
-
1990
- 1990-02-09 JP JP2028436A patent/JPH03232762A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5171312A (en) * | 1974-12-19 | 1976-06-21 | Tokyo Yogyo Kk | |
| JPS6011263A (en) * | 1983-06-24 | 1985-01-21 | 黒崎窯業株式会社 | Low heat conductivity basic refractories |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013005253A1 (en) * | 2011-07-06 | 2013-01-10 | ロザイ工業株式会社 | Magnesia-based refractory material |
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