JPH06115927A - Partial boride and amorphous refractory containing the same - Google Patents

Abstract

PURPOSE:To provide a metal functional agent existing in stable state without reacting with water even in a kneaded material of a non-neutral area and capable of sufficiently exhibiting a reinforcing function in an executing body. CONSTITUTION:This monolithic refractory is obtained by containing 0.1-20wt.% partial boride containing one or two or more kinds of Al, Si, Mg and Ca and 5-75wt.% boron or boron oxide. The partial boride is prepared by adding 5-75wt.% boron or boron oxide to a composition containing one of Al, Si, Mg and Ca or obtained by combining two or more kinds of Al, Si, Mg and Ca and melting the mixture and used by pulverizing the resultant mixture into desired size and forming into lump or powder. Thereby, an executing body of dense amorphous refractory excellent in mechanical strength and oxidation resistance is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous refractory material, particularly to a furnace for molten metal such as steel and non-ferrous metal and a furnace for an atmosphere furnace such as a heating furnace, and a hydraulic material suitable for lining a container. Regarding standard refractories.

In addition to general castable refractories that use alumina cement as a binder and low cement type castables that use a dispersant, etc., hydraulic amorphous amorphous refractories that use an inorganic binder such as phosphate or silicate as a binder. Is.

[0003]

2. Description of the Related Art Conventionally, as a refractory material used as a lining material for molten steel processing equipment, JP-B-60-2269, JP-B-61-303, and JP-A-59-107.
As described in JP-A-962, JP-A-61-266345, and the like, in MgO-C-based refractory bricks, phenol resin as a binder and Al, Si, M are used.
The addition and blending of alloys such as g and Ca have been successful in preventing carbon oxidation and improving mechanical strength during hot working.

On the other hand, similar attempts have been made for amorphous refractories, but the hydraulic substance used as a binder is often non-neutral, and in the kneaded product in the non-neutral region, metal is used. Cannot exist in a stable state and becomes a hydroxide due to a reaction with water, so that it is not possible to expect the effect of improving mechanical strength and the effect of preventing oxidation in the hot state as in the case of a standard refractory.

[0005] For example, in castables using alumina cement as a binder, the kneaded material exhibits strong alkalinity, and the added metals are converted into hydroxides by the following hydration reaction so as to have an antioxidant effect and heat resistance. The effect of improving the mechanical strength cannot be obtained.

[0006] _{^{Al + OH - + 2H 2 O}} → Al (OH)
₃ + H ₂ (g) ↑ On the other hand, Japanese Patent Publication No. 59-33549 and Japanese Patent Publication No. 61
As described in JP-A-40622, there is also an example of use as an explosion-preventing agent for a construction body by utilizing an exothermic reaction during hydration of a metal. However, also in this case, the hydrogen gas generated at the same time causes cracks and swelling, and a dense construction body, which is one of the important properties required for an amorphous refractory, cannot be obtained. For this reason, the addition of the metal as a strengthening agent is limited to an extremely small amount, and at the same time, a dense work body is obtained, and at the same time, the mechanical strength is improved and the antioxidant effect during hot in a high temperature range afterwards is achieved. Is difficult.

As a means for preventing the hydration of a metal added for the purpose of satisfying both of these requirements, Japanese Patent Publication No. 63-28874 proposes to add the metal by coating it with a resin.

However, there is an optimum size for resin coating, and in the case of fine powder, uniform coating is not easy and limits the particle size of the metal used. In addition, for irregular refractory materials, 10m
Since a large aggregate such as m and 5 mm is used, the coating is often peeled off due to rubbing with the aggregate during kneading, which is economically and practically problematic.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a metal function capable of exhibiting a strengthening function in a construction body in a stable state without reacting with water even in a kneaded material in a non-neutral region. To provide the agent.

Further, another object is to add a relatively large amount without being restricted by the particle size of the additive when the additive is added to the amorphous refractory, and a means capable of sufficiently exerting the strengthening function by the added metal. To provide.

With this, it is possible to obtain a dense irregular-shaped refractory work body, and at the same time, to improve the mechanical strength during hot and to obtain an antioxidant effect in a high temperature region later.

[0012]

Means for Solving the Problems The first invention of the present application is
A reinforcing agent for an irregular shaped refractory construction body, which comprises a partial boride containing 5 to 75% by weight of boron or boron oxide in one or more of 1, Si, Mg and Ca. is there.

The second invention of the present application is an amorphous refractory obtained by containing 0.1 to 20% by weight of the reinforcing agent composed of the partial boride.

The partial boride used in the present invention is Al, S.
A boron compound is prepared by adding 5 to 75% by weight of boron or boron oxide to a composition in which one or more of i, Mg, and Ca are combined, and then melting the composition to obtain a desired size. It is crushed into pieces and used in the form of lumps or powder.

Depending on the addition ratio of boron or boron oxide, a boride is formed, a large amount of metal remains, or an oxide is partially contained.

In the present invention, these are collectively referred to as partial borides.

[0017]

The present inventor has made the metal a partial boride,
We obtained the finding that hydration of metals can be prevented. The action of this partial boride is considered to prevent the boron ion, which is eluted from the partial boride in a very small amount, from hydrating the metal, but the details of the mechanism are not clear.

In order to prevent the hydration of the residual metal, it is necessary that the content of boron or boron oxide is 5% by weight or more. On the contrary, if it exceeds 75% by weight, boron alone remains. Boron simple substance is a typical light element, which is a very active substance as compared with other metals, causes explosive oxidation, and is extremely dangerous for use in the atmosphere. Therefore, the amount of boron or boron oxide in the partial boride is limited to the range of 5 to 75% by weight in terms of boron.

Further, the amount of boron or boron oxide is 5 to 75.
Even if the content is in the range of wt%, if a metal other than boron is left in excess, a very small amount of the residual metal may hydrate, but this is intentionally used to impart an explosion-proof function. This is also considered as an application example of the present invention.

[0020]

【Example】

Example 1 Table 1 shows an example applied to the low cement type castable of the present invention.

[0021]

[Table 1] As the castable, in each case, the compounding amount shown in Table 1 was 8% by weight of the externally added water, and this was kneaded to prepare 40 × 40 × 160 mm, which was almost JIS-R2553. A prototype sample was prepared according to the above. As the characteristics of the sample, the apparent porosity after firing at 1000 ° C. and the hot bending strength at 1400 ° C. are shown as the denseness of the sample.

As shown in Examples 1 to 3 of the table, both strength and compactness are compatible when the optimum range of partial boride is 0.1 to 20% by weight. In Comparative Example 2, since the boron component became excessive, the boron oxide-based low-melting material was formed, so that the bending strength was reduced during hot working. Comparative Examples 4 and 5 are examples in which Al powder was directly added as a metal, but if the amount is small, there is no strength improving effect, and if the amount is large, it becomes very porous due to the generation of hydrogen gas during hydration, and as a result, the strength is also remarkably high. Fell.

Example 2 Table 2 shows the effect of improving the oxidation resistance when applied to an alumina-carbonaceous castable refractory as a general castable refractory containing carbon powder.

[0024]

[Table 2] The trial production procedure is the same as that of the low cement type castable in Table 1 except that the amount of added water at the time of kneading is as large as 11% by weight. The oxidation resistance was measured by measuring the thickness of the decarburized layer obtained by cutting the center of the sample of 50φ × 50 mm after firing at 1000 ° C. for 3 hours. The smaller this value is, the better the oxidation resistance is.

The present invention, as shown in the comparison of Examples 5, 7 and 8, controls the amount of boron or boron oxide in the range of 5 to 75% by weight according to the purpose, and the metal to be combined therewith. Depending on the species, the rate of improvement in hot mechanical strength and oxidation resistance can be controlled.

[0026]

The present invention has the following effects.

(1) It is possible to freely add a metal having a strengthening function to an amorphous refractory.

(2) As a result, a dense irregular shaped refractory work body having excellent mechanical strength and oxidation resistance can be obtained.

(3) In addition to castable refractories, if it is hydraulic, it may include spray material, stamp material, and cast blocks that have been cast in advance to form stylized blocks such as weirs and other refractory structures. , A technology with a wide range of applications.

Claims (2)

[Claims] 1. A partial boride containing 5 to 75% by weight of boron or boron oxide in a composition in which one or more of Al, Si, Mg and Ca are combined. 2. A partial boride containing 0.1 to 20 parts by weight of boron or boron oxide in a composition in which one or more kinds of Al, Si, Mg, and Ca are combined.
A non-constant refractory material characterized by containing wt%.