JPS58204866A - Manufacture of carbon-oxide 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 The present invention relates to a method for producing a carbon-oxide type-1 material suitable for continuous casting refractories, converter interior refractories, and the like.

Oxides and refractories are widely used in the steel manufacturing field as refractories with excellent spall resistance and erosion resistance due to the presence of VC, a carbon component. However, it has not yet been perfected, and due to recent harsher usage conditions, there is still much room for improvement in its spall resistance and self-erosion resistance.

The present invention adds technical improvements to further improve the above characteristics of these carbon-oxide refractories.

Conventionally, pitch and phenolic resin have been known as binders for this refractory material. This binder is almost always used alone, and even when both are used together, the purpose is simply to improve the workability of the phenol resin, that is, to enable kneading at room temperature.

Therefore, as a result of repeated experiments to improve the performance of pitch and phenol resin as binders for carbon-oxide type 11 fire materials, the present inventors limited the pitch and phenolic resin to those with a constant @t-%, and When both were used in combination, it was possible to form a strong and dense carbosiboside in the tissue of a large fish.

That is, the HBS component of the present invention is 40% or more, and the QI component is 20% or more.
% or less pitch and number average molecular ffi (Mn) 1000
This is a method for producing a carbon-oxide yarn of 11 sizes, characterized in that the following phenol resin is coated with a binder having a weight ratio of 0.2 to 5 for the phenol resin.

Figure 1 and Figure 5 are part of the experimental results that led to the present invention.

In this experiment, we varied the materials and combination ratio of pitch and phenolic resin used as binders, and investigated the resulting changes in the properties of the refractory.

The target refractories were all made by kneading 30 wt% graphite and 7 Qwt% alumina with 10 wt% binder (outer layer), forming them at 1000 h/cm'' using a rubber lathe, and then reducing and firing them at 1000°C. It is something.

Figure 1 shows that the pitch and type of phenolic resin are constant,
This shows the relationship between the interest rate and the frequency of bending. When the ratio of pitch/phenolic resin is in a range other than 0.2 to 5, no improvement in bending strength is observed and the bending strength is no different from that when pitch or phenolic resin is used alone.

In the IA2 diagram, the ratio of pitch and phenolic resin is set to 1, and the relationship between changes in the BS component and QI acid component in the pitch component and bending strength is investigated. If the BS component of the pitch is 40% or less and the QI acid component is 20% or more, the bending strength of the fireworks is insufficient.

In addition, BS component and Q component are Beshizeshi irI solvent component (BS) using Beshizeshi as a bath agent, which is the most commonly used method for solvent fractionation of pitches, and Tenorishine solvent component (QI) using Shinorishi as a solvent. ).

On the other hand, as shown in FIG. 3, phenolic resins with a number average molecular Ill (Mn) of 1000 or less exhibit good bonding strength and strength.

The reason why a good strength improvement effect can be obtained by using pitch and phenolic resin in combination, and by setting the material and combination ratio within a specific VC range, is thought to be due to the following reasons. It will be done.

In other words, when using Jituchi Monomi as a binder,
A flow structure is formed as shown in FIG. 4, and cracks occur inside the vigitor during firing or use of the shipman Qlt+, and the fracture toughness of the carboxy bond structure decreases, resulting in a decrease in the strength as a carbon-oxide furnace material. On the other hand, when a single phenol resin is used as a vigitator, it becomes a glass-like structure as shown in Figure 5, and cracks occur during firing, but once cracks occur due to external force, the structure becomes uniform and the structure becomes transparent. The strength of the carbon-oxide 17-'It decreases due to the cracking of the conductive resistance.

On the other hand, in the present invention, pitch and phenol resin are used together, and the ratio and type of both are limited to a specific ratio as described above, so that the carbonized structure of the binder can be improved to t11. #
The fracture toughness and V-crack propagation resistance of carfosiphoside were improved, and the strength of carbon-oxide T material was improved.

Furthermore, since the material exhibiting ttJ' is an aggregate of l'-positive grains as shown in Figure 6, it can be expected to have excellent properties against erosion.

The carbon material used in the present invention may be one having a volatile content of 5% or less, such as scaly graphite, carbon coke, and raw graphite. On the other hand, the oxide is not limited to the above-mentioned alumina, but any of the conventionally known acidic, neutral, and basic refractory metal oxides can be used.

Moreover, the af! of the present invention! As long as it does not impair i-training,
A small amount of non-oxide type B4C, BN%SiC%Si3N4, etc. may be added.

Examples are shown below.

The table below shows alumina and magnesia as oxides, taraphite grains as carbon phase, various phenolic resins and pitch as binders, kneading and molding (100
0''@'on2), and after reduction firing (1000° C. x 3 hours), the results of measuring each physical property according to JIS are shown.

The refractories obtained in the above manner exhibit higher sporishing resistance and corrosion resistance than comparable conventional products, and are used as refractories for continuous casting and converter lining materials, which are subject to particularly severe usage conditions such as thermal shock from molten steel and melting damage. It is useful as a long-life furnace material.

[Brief explanation of the drawing]

Figure 1 is a graph showing the relationship between filler/phenol resin ratio and bending strength. Figure 2 is a graph showing the relationship between the BS component and QI acid component, and the song strength. wJ3 Figure 14 Graph showing the relationship between number average molecular wrinkles of phenol resin and bending strength. w, Figure 4, Figure 5, and Figure 6 are four (4) lines in the drawings, and the microscope after carbonization is 4 lines, and the magnification is 300 times. so io
so b. Supplementary note 11) Showa nL+ 〆月/θ11 1・f'l': Force closed application entry 4 Deputy! , l111II Higashi Seito Rdai 111-ku Marunouchi 2 I'
1 + No. 6, 2, Marunouchi, Shigesu Hill, 33°, sleeves, oath, specification of the application, to-H, and the matter was closed. The 11th market (・ζ [1111 Suhorusha]) in the 7th page of ``Clothing'' in ``Ki 1'' is written as ``Tai Subo 1 Shi・1 Sat: 3)''. 2. In the 1st column of the 7th message "table", write "1 岨 Bath 14 sex" if It'-. . 3 wa 0,7 Page corner 艷 Bottom 1 cho [2] Phenol resin and pitch ratio Vi So w ratio (1
:l). ” The next sentence is faint. join. r3) tsoo°C x 15 minutes → Cycle red 50 x 50 x 0am where transfer was observed in water cooling 4) Resistance to magnesial steel, 1
Value after soaking at 600°C
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1116 No. 2 To Marunouchi Tsumesu Hill 330 Name (366
71 Teru Taniyama i, male 5, Ura+L-iFr7 force 1111 11 call+11ζ7 f, and moon J'/ ++ draw
11., 1 What are the F Ht matters in the specification and drawings of this application? 41IJ■-
・ 2 (t″t. Note 1, 8th fi 14-1611 1 Fig. 4, Fig. 5, ...300 (i ii de Aisaki, l 1 No. 41'Xl, Figures 5 and 6 show the structure of Sabadai after carbonization. of/
1. Figure 5 shows the crow structure in the case of Phenol Resik*H8 - Small - 4-0 Figure 6 shows heathering! As shown in the following, the effect of using a combination of hitch and phenol resin is ``1-o''. 2. 1 in the drawing? Figure 4'' 1 Figure 5'' 1 Figure 6'' are shown separately <N] 1't-4':', ), -. Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] A pitch with a BS component of 40% or more and a QI component of 20% or less,
A carbon-moldide-based refractory characterized in that a phenolic resin having a number average molecular weight of 1 (Mn) 1000 or less is combined with a binder having a pitch/phenol resin ratio of 0.2 to 5 to 1-L+. Production method.