JPH04317458A - Magnesia-chromia refractory - Google Patents
Magnesia-chromia refractoryInfo
- Publication number
- JPH04317458A JPH04317458A JP3085463A JP8546391A JPH04317458A JP H04317458 A JPH04317458 A JP H04317458A JP 3085463 A JP3085463 A JP 3085463A JP 8546391 A JP8546391 A JP 8546391A JP H04317458 A JPH04317458 A JP H04317458A
- Authority
- JP
- Japan
- Prior art keywords
- flux
- sio2
- cao
- refractories
- magnesia
- 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.)
- Granted
Links
- 230000004907 flux Effects 0.000 claims abstract description 39
- 238000002844 melting Methods 0.000 claims description 15
- 230000008018 melting Effects 0.000 claims description 15
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 33
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 abstract description 32
- 239000011819 refractory material Substances 0.000 abstract description 20
- 229910052681 coesite Inorganic materials 0.000 abstract description 18
- 229910052906 cristobalite Inorganic materials 0.000 abstract description 18
- 239000000377 silicon dioxide Substances 0.000 abstract description 18
- 229910052682 stishovite Inorganic materials 0.000 abstract description 18
- 229910052905 tridymite Inorganic materials 0.000 abstract description 18
- 235000012239 silicon dioxide Nutrition 0.000 abstract description 15
- 238000010304 firing Methods 0.000 abstract description 10
- 238000005260 corrosion Methods 0.000 abstract description 8
- 230000007797 corrosion Effects 0.000 abstract description 8
- 239000012535 impurity Substances 0.000 abstract description 6
- 239000000126 substance Substances 0.000 abstract description 5
- 239000007858 starting material Substances 0.000 abstract 2
- 239000000395 magnesium oxide Substances 0.000 description 15
- 239000002994 raw material Substances 0.000 description 15
- 239000000203 mixture Substances 0.000 description 12
- 238000007670 refining Methods 0.000 description 7
- 229910000831 Steel Inorganic materials 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000010959 steel Substances 0.000 description 5
- 230000003628 erosive effect Effects 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 229910052804 chromium Inorganic materials 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 229910052596 spinel Inorganic materials 0.000 description 3
- 239000011029 spinel Substances 0.000 description 3
- 229910002974 CaO–SiO2 Inorganic materials 0.000 description 2
- 229910017970 MgO-SiO2 Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000010587 phase diagram Methods 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 229910019830 Cr2 O3 Inorganic materials 0.000 description 1
- 229910017344 Fe2 O3 Inorganic materials 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 description 1
- 238000013003 hot bending Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、金属精錬用の容器等に
使用される耐火物に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to refractories used in metal refining containers and the like.
【０００２】0002
【従来の技術】マグネシア・クロミア耐火物（以下、マ
グクロ耐火物という）は、金属精錬用耐火物として優れ
た特性を有する耐火物であり、特にＤＨ，ＶＯＤなどの
溶鋼の二次精錬関係には欠かすことの出来ない材質であ
る。近年に至っては、高純度鋼、高品質ステンレス鋼や
その他の特殊鋼種溶製に伴って、従来の耐火物では耐用
が限界に達しており、材料技術に対する要求が高まって
いる。[Prior Art] Magnesia-chromia refractories (hereinafter referred to as magnesia refractories) are refractories with excellent properties as refractories for metal refining, and are particularly suitable for secondary refining of molten steel such as DH and VOD. It is an indispensable material. In recent years, with the production of high-purity steel, high-quality stainless steel, and other special steel types, conventional refractories have reached their service life limits, and demands for material technology are increasing.
【０００３】マグクロ耐火物に関しては、長い歴史と種
々の材料改革、特に全体の組成や配合技術、添加物効果
例えば金属，合金や炭化物の添加などが行われてきた。
ところが、このような方法では炉材コストが高くなるば
かりでなく、材料開発に限界を生じ、特に近年の１７０
０℃以上の厳しい精錬条件下では限界に達してくる。そ
の結果炉体寿命も１／２程度まで低下しているケースが
多く見られる。[0003] Maguro refractories have a long history and various material innovations, particularly in terms of overall composition, compounding technology, and additive effects such as the addition of metals, alloys, and carbides. However, this method not only increases the cost of furnace materials, but also limits material development, especially in recent years.
It reaches its limit under severe refining conditions at temperatures above 0°C. As a result, there are many cases where the life of the furnace body is reduced to about 1/2.
【０００４】0004
【発明が解決しようとする課題】マグクロ耐火物は、元
来マグネシアにクロム鉱石を添加、またはこれらを電気
溶融した原料が使用される。この原料を通常の方法で製
造した場合、焼成後の組織を観察すると、耐火物を構成
する粒子の間にフラックスと呼ばれる不純物成分が析出
している。このフラックスは耐火原料中に存在する成分
であるが、一般的には原料の主要成分と異なり、また、
融点もかなり低いものと考えられてきた。したがって、
マグクロ耐火物の耐食性や熱間の諸物性を向上させるに
は、高純度化する目的でこれらの成分をできるだけ少な
くするためにクロム鉱石の産地を限定したり、マグネシ
アのグレードを向上させるなどの手段を余儀無くされて
いた。[Problems to be Solved by the Invention] Maguro refractories are originally made from magnesia with chromium ore added thereto, or by electrically melting these. When this raw material is manufactured by a normal method, when observing the structure after firing, an impurity component called flux is precipitated between the particles that make up the refractory. This flux is a component that exists in refractory raw materials, but it is generally different from the main components of the raw materials, and
It has also been thought that the melting point is quite low. therefore,
In order to improve the corrosion resistance and hot physical properties of magnesia refractories, it is necessary to limit the production area of chromium ore and improve the grade of magnesia in order to reduce these components as much as possible for the purpose of high purity. was forced to do so.
【０００５】本発明は、マグクロ耐火物の組織中に存在
するフラックスの成分調整を行うことによってより高品
質な耐火物を製造することを目的とする。The object of the present invention is to produce higher quality refractories by adjusting the composition of flux present in the structure of maguro refractories.
【０００６】[0006]
【課題を解決するための手段】本発明者は、マグクロ耐
火物の諸特性が、フラックスの成分調整とその量を厳密
に制御する事によって著しく向上することを突き止めて
本発明を完成させた。すなわち、本発明のマグネシア・
クロミア耐火物は、ＭｇＯ−ＳｉＯ２ −ＣａＯ系を主
成分とするフラックスを含有し、かつそのフラックスの
融点が１７００℃以上であることを特徴とする。[Means for Solving the Problems] The present inventors have completed the present invention by discovering that various properties of maguro refractories can be significantly improved by adjusting the composition of flux and strictly controlling its amount. That is, the magnesia of the present invention
Chromia refractories are characterized in that they contain a flux whose main component is MgO-SiO2-CaO, and the melting point of the flux is 1700°C or higher.
【０００７】[0007]
【作用】マグクロ耐火物の耐食性や熱間での諸物性を向
上させるには、耐火物の焼成中に粒子間に析出してくる
フラックス成分を制御することが重要である。この制御
されたフラックス成分は、マグクロ耐火物の主に耐食性
と熱間強度の向上に有効な役割を果たす。[Operation] In order to improve the corrosion resistance and various hot physical properties of maguro refractories, it is important to control the flux components that precipitate between particles during firing of the refractories. This controlled flux component plays an effective role in mainly improving the corrosion resistance and hot strength of the maguro refractory.
【０００８】通常耐火物を製造する場合は、原料から導
入される不純物を制御することなくそのまま粉砕、成形
し焼成するが、この場合、耐火性の低いフラックスが生
成し、耐火物の元来の特性を著しく低下させてしまう。
これを防止するために高純度の原料を使用することも考
えられるが、経済性の点から得策とは言えない。[0008] Normally, when producing refractories, impurities introduced from the raw materials are crushed, molded, and fired without controlling them. The characteristics will be significantly deteriorated. Although it is conceivable to use highly purified raw materials to prevent this, it is not considered a good idea from an economic point of view.
【０００９】本発明においては、通常のマグクロ耐火物
の製造の場合と同様に、マグネシアやクロム鉱石などを
原料とするか、これらを電気溶融したものを原料とする
。しかし、焼成中に生成するフラックスが焼成後の耐火
物の特性を支配することから、原料調整または混合段階
で予め生成するフラックスの成分調整を行う。[0009] In the present invention, as in the case of manufacturing ordinary maguro refractories, magnesia, chromium ore, etc. are used as raw materials, or the raw materials obtained by electrically melting these are used as raw materials. However, since the flux produced during firing controls the properties of the refractory after firing, the components of the flux produced are adjusted in advance during the raw material adjustment or mixing stage.
【００１０】フラックスはその化学成分が主にＭｇＯ，
ＳｉＯ２ ，ＣａＯから構成されている。二次スピネル
成分が溶け込んでいる場合は、Ｃｒ２ Ｏ３ ，Ａｌ２
Ｏ３ ，Ｆｅ２ Ｏ３ が少量入っている。耐火原料
中の不純物に関して、ＳｉＯ２がＣａＯに比べ比較的多
い場合はＭｇＯ−ＳｉＯ２ を主成分とするフラックス
が生成し、逆の場合はＣａＯ−ＳｉＯ２ を主成分とす
るフラックスが生成しやすい。ここで、原料中の不純物
は全量がフラックスになるわけではなく、ＣａＯやＳｉ
Ｏ２ の一部はマグネシアに取り込まれ、その残部が前
述した組成を主成分としてマグネシアの粒子間に析出す
る。このマグネシアの粒子間に析出したものをフラック
スという。[0010] The chemical components of flux are mainly MgO,
It is composed of SiO2 and CaO. If secondary spinel components are dissolved, Cr2 O3, Al2
Contains small amounts of O3 and Fe2 O3. Regarding impurities in the refractory raw material, if SiO2 is relatively large compared to CaO, a flux containing MgO--SiO2 as the main component is likely to be produced, and in the opposite case, a flux containing CaO--SiO2 as the main component is likely to be produced. Here, not all of the impurities in the raw material become flux, but CaO and Si
A portion of O2 is taken into magnesia, and the remainder precipitates between magnesia particles, with the above-mentioned composition as the main component. The substance that precipitates between the magnesia particles is called flux.
【００１１】フラックスの組成と量の制御は、使用する
原料の化学成分を分析しておき、焼成後の耐火物中に存
在するフラックスの化学分析をＸ線やＥＤＸ（エネルギ
ー分散型Ｘ線マイクロアナライザー）などの装置を使用
して再度行う。両者の差異からフラックスしとて寄与す
る不純物量を推定し、フラックスがＭｇＯ−ＳｉＯ２
−ＣａＯ系を主成分とし、その融点が１７００℃以上と
なる組成および量的条件を満たすように、ＳｉＯ２ ま
たはＣａＯを原料に添加することによってフラックスの
成分調整を行う。[0011] The composition and amount of flux can be controlled by analyzing the chemical components of the raw materials used, and by using X-rays or EDX (energy dispersive ) or similar device and try again. The amount of impurities contributing to the flux is estimated from the difference between the two, and the flux is MgO-SiO2.
The composition of the flux is adjusted by adding SiO2 or CaO to the raw material so that it has a -CaO system as its main component and satisfies the compositional and quantitative conditions such that its melting point is 1700° C. or higher.
【００１２】本発明において、フラックスの融点は、フ
ラックスを構成する主成分であるＣａＯ，ＭｇＯ，Ｓｉ
Ｏ２ の三元系状態図から推定される融点を指す。この
融点を１７００℃以上とした理由は、近年の溶鋼の二次
精錬炉は１７００℃以上の操業が多く、耐用性のある耐
火物とするにはフラックスの融点もその温度近傍以上と
する必要性があるからである。組成面に関しても、Ｍｇ
Ｏ−ＳｉＯ２ またはＣａＯ−ＳｉＯ２ を主成分とす
るフラックスに関して、前者はＣａＯを、後者はＭｇＯ
を３０重量％以下含むフラックスを比較的容易に生成す
る。さらにＭｇＯ−ＳｉＯ２ 及びＣａＯ−ＳｉＯ２
を主成分とする系においては、フラックスの融点を１７
００℃以上とするために、ＭｇＯ／ＳｉＯ２ のモル比
を１．４０〜６．００の範囲に、ＣａＯ／ＳｉＯ２ の
モル比を１．４５〜６．１０の範囲に設定するのが望ま
しい。このフラックスの量については、多すぎた場合は
耐食性の低下を招き、少なすぎる場合には焼成段階で生
成する二次スピネルの生成を著しく低下させる恐れがあ
るため、フラックスの合量が５〜０．５％の範囲が望ま
しい。In the present invention, the melting point of the flux is determined by the melting point of CaO, MgO, and Si, which are the main components of the flux.
Refers to the melting point estimated from the ternary phase diagram of O2. The reason why this melting point was set at 1,700°C or higher is that in recent years, many secondary molten steel refining furnaces are operated at temperatures of 1,700°C or higher, and in order to make a durable refractory, the melting point of the flux must also be around that temperature or higher. This is because there is. Regarding the composition, Mg
Regarding fluxes whose main components are O-SiO2 or CaO-SiO2, the former contains CaO, and the latter contains MgO.
It is relatively easy to produce a flux containing 30% by weight or less of Furthermore, MgO-SiO2 and CaO-SiO2
In a system whose main component is
In order to maintain the temperature at 00 DEG C. or higher, it is desirable to set the MgO/SiO2 molar ratio in the range of 1.40 to 6.00 and the CaO/SiO2 molar ratio in the range of 1.45 to 6.10. Regarding the amount of this flux, if it is too large, it will lead to a decrease in corrosion resistance, and if it is too small, there is a possibility that the formation of secondary spinel generated in the firing step will be significantly reduced. A range of .5% is desirable.
【００１３】[0013]
【実施例】以下、実施例により本発明を詳細に説明する
。ここでは表１に示す組成の電融マグクロクリンカーを
ベースとし、適量のＣａＯ及びＳｉＯ２ を添加するこ
とによって焼成後に生成するフラックスの組成を変えて
いる。また、試料の作成は通常の耐火物の製造方法に従
っており、焼成温度は１８５０℃とした。[Examples] The present invention will be explained in detail below with reference to Examples. Here, an electrofused maguro clinker having the composition shown in Table 1 is used as a base, and the composition of the flux produced after firing is changed by adding appropriate amounts of CaO and SiO2. In addition, the samples were prepared in accordance with a normal refractory manufacturing method, and the firing temperature was 1850°C.
【００１４】表２に実施例としてフラックス組成を制御
した８種類の試料の組成と特性を示す。ここで生成した
フラックスは、焼成後の試料をＥＤＸで分析した。表中
にはＭｇＯ／ＳｉＯ２ またはＣａＯ／ＳｉＯ２ 比（
モル比）を示す。また、その下欄にはＣａＯ−ＭｇＯ−
ＳｉＯ２ 三元状態図から推定されるフラックスの融点
を示した。特性に関しては１５００℃における熱間の曲
げ強度及びスラグ浸漬法を用いた浸食実験の結果を示し
た。ここで示す溶損指数は、実施例６の溶損量を１００
としたときの各試料の値を指数で表している。実施例１
〜８の試料は、いずれもフラックスの融点が１７００℃
以上であり、熱間強度は１００ｋｇ／ｃｍ２ 以上、溶
損指数も１００以下の耐食性に優れた値を示している。Table 2 shows the compositions and characteristics of eight types of samples in which the flux composition was controlled as an example. The flux produced here was analyzed by EDX on a sample after firing. In the table, MgO/SiO2 or CaO/SiO2 ratio (
molar ratio). In addition, in the column below, CaO-MgO-
The melting point of the flux estimated from the SiO2 ternary phase diagram is shown. Regarding the properties, the hot bending strength at 1500°C and the results of an erosion experiment using the slag immersion method are shown. The erosion index shown here is the erosion amount of Example 6 by 100.
The value of each sample is expressed as an index. Example 1
The melting point of the flux for all samples ~8 is 1700℃
Thus, the hot strength is 100 kg/cm2 or more, and the erosion index is 100 or less, indicating excellent corrosion resistance.
【００１５】表３に比較例として５種類の試料を示す。
比較例１〜４ははＭｇＯ／ＳｉＯ２ またはＣａＯ／Ｓ
ｉＯ２ 比が小さく、したがって生成するフラックスの
融点も低く、熱間強度及び耐食性で著しい低下を生じて
いるのが判る。また、比較例５は高純度原料を添加し、
フラックスの含有量を低くしたものであり、フラックス
の融点は高いがその量が非常に少ないため、焼成時に二
次スピネルの生成が阻害され、実施例１に比べて著しく
特性が低下しているのが判る。Table 3 shows five types of samples as comparative examples. Comparative Examples 1 to 4 are MgO/SiO2 or CaO/S
It can be seen that the iO2 ratio is low and therefore the melting point of the produced flux is low, resulting in a significant decrease in hot strength and corrosion resistance. In addition, in Comparative Example 5, high purity raw materials were added,
This is because the flux content is low, and although the melting point of the flux is high, the amount is very small, so the formation of secondary spinel is inhibited during firing, and the properties are significantly deteriorated compared to Example 1. I understand.
【００１６】[0016]
【表１】[Table 1]
【００１７】[0017]
【表２】[Table 2]
【００１８】[0018]
【表３】[Table 3]
【００１９】[0019]
【発明の効果】本発明により極めて耐食性が高く、また
熱間強度も高いマグクロ耐火物の製造が簡便な方法で達
成できる。本発明はマグクロ耐火物の特性を飛躍的に高
めることが可能で、原料として安価なＣａＯやＳｉＯ２
を添加しフラックスの成分調整を行うだけなので経済
的にも非常に魅力のあるものである。According to the present invention, a maguro refractory having extremely high corrosion resistance and high hot strength can be produced by a simple method. The present invention can dramatically improve the properties of maguro refractories, and uses inexpensive CaO and SiO2 as raw materials.
It is economically very attractive as it only requires adding and adjusting the flux composition.
【００２０】また、鉄鋼精錬分野においては今後高級鋼
種の要求が高まることが予想されることから、操業の高
温化を伴う二次精錬用炉の寿命を低下させること無く安
定した耐用を示すことが期待できる。[0020] In addition, in the steel refining field, it is expected that the demand for high-grade steel will increase in the future, so it is necessary to demonstrate stable durability without reducing the life of secondary refining furnaces, which involve high-temperature operation. You can expect it.
Claims (1)
分とするフラックスを含有し、かつそのフラックスの融
点が１７００℃以上であることを特徴とするマグネシア
・クロミア耐火物。1. A magnesia-chromia refractory characterized by containing a flux mainly composed of MgO-SiO2-CaO system and having a melting point of 1700°C or higher.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3085463A JP3009067B2 (en) | 1991-04-17 | 1991-04-17 | Magnesia-Chromia refractories |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3085463A JP3009067B2 (en) | 1991-04-17 | 1991-04-17 | Magnesia-Chromia refractories |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04317458A true JPH04317458A (en) | 1992-11-09 |
| JP3009067B2 JP3009067B2 (en) | 2000-02-14 |
Family
ID=13859584
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3085463A Expired - Lifetime JP3009067B2 (en) | 1991-04-17 | 1991-04-17 | Magnesia-Chromia refractories |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3009067B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100417712B1 (en) * | 1998-12-29 | 2004-03-26 | 주식회사 포스코 | Steel Filling Material |
| JP2011179793A (en) * | 2010-03-03 | 2011-09-15 | Mitsubishi Materials Corp | Magnesia-chrome refractory, copper smelting furnace, and continuous copper metallurgy furnace |
-
1991
- 1991-04-17 JP JP3085463A patent/JP3009067B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100417712B1 (en) * | 1998-12-29 | 2004-03-26 | 주식회사 포스코 | Steel Filling Material |
| JP2011179793A (en) * | 2010-03-03 | 2011-09-15 | Mitsubishi Materials Corp | Magnesia-chrome refractory, copper smelting furnace, and continuous copper metallurgy furnace |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3009067B2 (en) | 2000-02-14 |
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