JPS6065771A - Carbon fiber-containing refractories - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical outline] The present invention is applicable to a furnace 1 for making pig iron or steel, such as a blast furnace, a pig iron mixer, a gutter, a converter, an electric furnace, a DH furnace, an RH furnace, a ladle, a tundish, etc. This invention relates to carposi-containing refractory materials used for refractory furnace materials, nozzles, etc.

[Background technology]

Carposi-containing refractory materials have been known for a long time, and carbo-y is widely used because it does not mix well with molten metal and has the effect of preventing the refractory material from being significantly damaged by molten metal. Then, this fireproofing material hardening resin bisitor is mixed, and after molding this mixture, for example, phenol resin is used as a thermosetting resin. When using this t20.0
An unfired refractory material made by hardening the phenolic resin by heating it to a temperature of about ℃? I'm trying to get it. When this unfired refractory material is used as a furnace material or nozzle in an actual machine, the molten metal comes into contact with the refractory material, and the refractory material is fired at the high temperature of the molten metal, carbonizing the carbon component of phenol III. Refractory material by carboshiboside? It is a strong bond. Of course, the above unfired ml
Fire? It is also possible to make a fired refractory material product by firing it at a high temperature and use it in this state. Although this refractory material has the above-mentioned excellent properties due to the carbon content, it has a major problem that can be said to be fatal. In other words, when the carbon component of the phenol resin is carbonized by firing with the molten metal, a part of the carbon component and other components become H, O, G.
o2. If the refractory undergoes a large volumetric contraction as a result of CO, etc., f'L is emitted from the refractory, resulting in a gap in the joint of the refractory, which may cause molten metal to leak, resulting in an accident. There was a risk that this could cause an outbreak.

The present invention has been made in view of the above points, and provides a carposi fiber-containing refractory material that can reduce volumetric shrinkage during firing, has excellent thermal shock resistance, and has excellent bending strength. The purpose is to provide

[-Disclosure of the invention]

Carbon #1 kept in this invention! Fiber-containing refractory materials have the following properties:
The present invention is characterized in that it is made by blending a thermosetting resin binder in which carbon fibers are dispersed and mixed into a fire-resistant aggregate containing J.

As the refractory aggregate, it is preferable to use carposi as its main component or to use alumina as another main component.

Of course, in addition to alumina, magnesia is used as a fire-resistant aggregate.
It is also possible to use materials such as matanesia earth resin and SiC. The blending ratio of refractory aggregate and Carposi 7 is 70 by weight.
-99: About 30-1 is preferable. The carposi can be natural or artificial, such as scaly graphite or earthy graphite? Carbon black, electrode scrap, pitch coke, smokeless carbon, etc. can be used in the form of carbon black, electrode scrap, pitch coke, and smokeless carbon. It has the effect of preventing this. As for the alumina in the fire-resistant aggregate, Hato 03 (11' containing 70% by weight or more?) is preferably used, and of course the particle size is appropriately adjusted before use. Alumina is effective in improving fire resistance. In addition to the above-mentioned carposis and fire-resistant aggregates, metals such as aluminum metal, zinc metal, and silicon gold, or SiC, Si, N, BN% B, etc., can be used to improve oxidation resistance.
It is also possible to incorporate nitride carbides such as , C, etc.

What are the various commercially available carposi fibers to be blended in the present invention? Although it can be used.

As for its dimensions, the outer diameter is 10~30μ, and the thickness is 0°2~
Preferably, it has a value of about 40 MIn. That is, the outer diameter is 10
If it is less than 30μ, it is difficult to defibrate carposi fibers and it is difficult to obtain a reinforcing effect. If it exceeds the diameter, the diameter will be too large and the dispersibility into the resin will be poor. Also, the length is 0.2
If the WR is less than WR, the reinforcing effect of the h-bon fiber is insufficient, resulting in prevention of volumetric contraction and thermal shock.

It is difficult to demonstrate the effect of improving bending strength.

If the length exceeds 40wn, the dispersibility into the resin will deteriorate. In addition, aspect ratio (fiber length/fiber diameter)
is preferably 30 or more. The blending amount of carbon fiber is variously set depending on the required VC, but it is 0.1 to 15 parts by weight per 100 parts by weight of both carbon and fire-resistant aggregate.
It is preferable to have a weight ratio of about 2%. If it is less than 0.1% by weight, the reinforcing effect of the carposi fibers will be insufficient, and if it exceeds 15% by weight, the strut height will increase and uniform dispersion will become difficult.

Then, a molding material for a fireproof material is prepared by blending carbon fibers and a thermosetting resin vigitator with the fireproof aggregate blended with carposi. Although the thermosetting resin is not limited in any way, phenolic resins such as relyl or novolatile resins are commonly used. The blending amount of thermosetting resin binder is not particularly limited, but aggregate component 10
It is preferably about 2 to 15 parts by weight based on 0 parts by weight. If it is less than 2 parts by weight, the paint effect cannot be fully exhibited and the strength of the refractory material will be low; if it exceeds 15 parts by weight, the amount of components released during firing will increase, causing large volumetric shrinkage and being disadvantageous in terms of cost. It is what it is. Here, various methods can be considered for blending the carbon fibers. For example, it is possible to mix fire-resistant aggregate and thermosetting aggregate with oxidizable 10 MII and 30 sun, and directly insert carposi fiber into 3 △ 10 s. There is a problem in that carbon fibers are very difficult to disperse. Therefore, in the present invention, carbon fibers are completely mixed in a thermosetting resin binder in advance, and the carbon fibers are wetted with a thermosetting resin binder. By putting it into a thirty-six-foot tank and kneading it with fire-resistant aggregate,
Carposi fiber in the wet seat? This ensures uniform dispersion and mixing with the refractory aggregate.

Next, the molding material prepared as described above is put into a mold and press-molded, and this is dried and hardened under heating conditions of, for example, about 200°C to form an unfired refractory material. obtain. this? ! - Real! Molten metal VC is used for festival pig iron and steel making.
High illumination of molten metal when brought into contact! (about 1600℃) fireproof material? By firing.

h- by carbonizing the carbon component of the thermosetting resin in the fireproof material.
Fired refractory resin to act as a ponbond? It's something you get.

The refractory brick TIc obtained as described above has a force of -
Bo: JkJ1. Shrinkage of bricks during firing due to the reinforcing effect of fiber dispersion? It is possible to improve thermal shock resistance and bending strength,
Moreover, the carbon fibers are of the same quality as the carposi existing in the matrix part of Ren J5, and are compatible with Garashiga, making it possible to effectively exert the above-mentioned reinforcing effect. A void? It is possible to prevent large melt loss due to molten metal without causing any risk of damage. The carbon fibers in the casing have little resistance to molten metal, so in combination with carposi as an aggregate, it is possible to further reduce erosion caused by molten metal.

This is illustrated by the rT embodiment of the present invention.

Example 1> Alumina (particle size 3-1 ttva is 206@%1 particle size 1
~0 threshold is 60% by weight) 80 parts by weight, 20 parts by weight of sea bream graphite, 8 parts by weight of reel type phenolic resin and 1 part by weight of outer diameter
0.5 parts by weight of carposi fibers with a thickness of 5 μm and a thigh low were blended, and the mixture was kneaded for 30 minutes. Here, the sole-type phenol (the sealant and the carposi fiber were mixed and kneaded in advance, and this mixture was blended in step 7).

Next, the mixture was molded by pressing at a pressure of 1000/Crl, and then heated and dried at 11200° C. for 24 hours to obtain a refractory.

<Example 2> A refractory material was obtained in the same manner as in Example 1 except that 5 parts by weight of carbon fiber was used.

<Example 5> Carbon fiber? A refractory material was obtained in the same manner as in Example 1 except that 10 parts by weight was used.

<Example 4> Macnesia (20% by weight of particles with a particle size of 3 to 1 mm, 6% by weight of particles with a particle size of 1 to 1 mm) was used instead of alumina.
, refractory material as in Example 1? Obtained.

Comparative Example 1> A refractory material was obtained in the same manner as in Example 1 except that the carposi fiber was not used.

Comparative Example 2 The same procedure as in the example was carried out except that alumina and scale graphite were mixed with all of the 7 fibers and kneaded for 5 minutes, and in the first stage, a reel type phenol resin was further blended and kneaded for 3olI+. A refractory material was obtained in the same manner.

Obtained as above fc Examples 1 to 4 and Comparative Example 1.2
The refractory material was subjected to heat treatment at 1000° C. in a casing with gradually increasing temperature, and the weight loss and volume loss were measured. The results are shown in the attached drawings. In addition, in the Taraf in Figure 1, the solid line indicates weight loss, and the dotted line indicates volume reduction? The upper example is shown in Figure 1, the second example is shown in Figure 2, the example convex is shown in Figure 5, and the actual example is shown in Figure 1.
The regular meeting is shown in Figure Φ, Comparative Example 1 is shown in Figure 5, Comparative Example 2 is shown in Figure 6.
Shown in the figure. According to the results, Examples 1 to 4 and Comparative Examples 1.2 all have almost the same weight and fiber, but Examples 1 to 4, which have a fine carposi bond, do not have the same weight. Comparative Example 1. It was confirmed that the volume reduction was smaller than that of Comparative Example 2, in which the carposi fiber was blended without being mixed with the pinter in advance.

The following table shows the results of thermal shock resistance tests and bending strength tests performed on the refractory materials of Examples 1 to 4 and Comparative Examples 1 and 2. In addition, the thermal shock resistance test was conducted by repeating heating at 1500°C for 15 minutes, 1T, and water for 15 minutes, and measuring the cycle until cracks appeared in the refractory material. From the results shown in the table above, it was found that carposi fibers were The ones of Examples 1 to 4 that were blended, those of Comparative Example 1 that were not blended, and the carbon fibers were pre-baked! It is confirmed that the thermal shock resistance and bending strength are superior to that of Comparative Example 2, which was used without being mixed with 2-.

〔Effect of the invention〕

As described above, according to the present invention, the fireproof material can be completely reinforced by dispersing and blending the h-bon fibers,
Volumetric shrinkage when refractory material is fired? It is possible to reduce the amount of heat and improve the thermal shock resistance and bending strength of the refractory material. The fibers are thermosetting (because they are dispersed and mixed in the thermosetting resin).

Carbon fibers are uniformly dispersed in the refractory material, and the above effects can be more effectively exhibited.

[Brief explanation of drawings]

Figures 1 to 0 show the temperature, body st reduction, and weight t of refractory materials.
It is a rough figure showing the relationship with tM low. Figure 1 (6C) Figure 2 ('C) Figure 5 ('C) Figure 16 ('C)

Claims (1)

[Claims] (1) Is it made by blending a thermosetting resin bisitor in which carbon fibers are dispersed and mixed into a fire-resistant aggregate containing carposi? Features of carbon fiber-containing fireproof material