JPS59135273A - Adhesive for refractory and bonding method - Google Patents

Abstract

PURPOSE:To provide an adhesive having excellent corrosion resistance, high- temperature strength, etc. and suitable for use in bonding refractories mainly composed of MgO to each other, by blending MgO refractory powder, metallic aluminum powder and metallic silicon powder with a phenolic resin. CONSTITUTION:5-30pts.wt. MgO refractory powder having a particle size of 200 mesh or below, 5-30pts.wt. metallic aluminum powder having a particle size of 200 mesh or below and 1-10pts.wt. metallic silicon powder having a particle size of 200 mesh or below are blended with 100pts.wt. phenolic resin to obtain the desired adhesive for refractories. This adhesive is applied to surfaces between refractories mainly composed of MgO to join them to each other and heat-treated to cure the phenolic resin, whereby they are bonded to each other. When the adhesive is heated at a high temp., metallic aluminum is reacted with MgO to form spinel having excellent corrosion resistance, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to refractories, particularly to refractory adhesives and adhesive methods containing MgO as a main component.

Mg0-C! (Magnesia-carbon) refractories have been widely used in converters and ladles in recent years, but depending on the shape, it is difficult to form them in one piece, and it is necessary to manufacture them by laminating bricks of appropriate size. A situation has arisen. Furthermore, even in ordinary furnace construction, it is often necessary to bond refractories together.

In such cases, refractory mortars are generally used, or they often do not have sufficient adhesive strength at room or high temperatures. Furthermore, in special cases, such as when bonding refractories with well-polished surfaces, the use of mohayatar is undesirable in terms of dimensional accuracy because the layer thickness □ tends to increase. There is. 1. For Komu, sake, fire - glue and shi: But,
: Various products are commercially available or have been proposed, but the main ones are those based on 8 1.02 quality, which develops strength at both temperatures by turning into glass after heating, and at high temperatures.

For example, at temperatures above 1500'C'', the strength is not high, and the corrosion resistance is also insufficient. desired.

The present invention was discovered as a result of various studies from this point of view, and is essentially based on phenolic resin, in which Mg'6 refractory powder, metal aluminum (A1), and metal silicon (Sl) are added. ) The adhesive and bonding method in which each powder is present are summarized in □. □The present invention may be an adhesive in which each component is mixed in advance in different proportions, or one or two of each component may be prepared in advance.
Prepare a combination of the above as necessary, and use it on the spot when constructing a furnace or when gluing refractories together.
It may also be applied sequentially between the refractories and bonded together.

Hereinafter, in order to make it easier to understand, the explanation will be given using a pre-mixed adhesive as an example.

□, a preferred embodiment of the present invention is a phenonyl resin 10
The formula for 0 parts by weight (the same applies hereinafter) is as follows.

Metallic aluminum 5 to 30 parts Metallic silicon 1yIQ part MgO-based powder 5 to 30 parts In the present invention, phenolic resin% A1. The reasons for the use of Si and MgO powders and their preferred proportions are as follows.

○Phenol resin is the basis of □ this adhesive, and it is cured by the bonding process (about 2 oO ℃ is sufficient) and gives room temperature strength. □ After being exposed to high temperatures, It is necessary that as much carbon as possible remains as possible, and the phenol resin used in ordinary MgO-0 bricks is sufficient.

“○Metal aluminum is oxidized to form 3A120H at temperatures above about 600℃, and further reacts with MgO components at high temperatures of about 1400℃ and above to form spinel (Mgo・A120H).
12O+ ), which contributes to the strong adhesion of refractories to each other, and this spinel-forming bond is caused by the presence of M, Go powder, and the refractory in the adhesive, in which ego is the main component. If so, these MgO components are brought about by which reaction.

2 In addition, these alumina and spinel formations are accompanied by volumetric expansion, which has the effect of densifying the joint surface1.
．． The refractory is C (carbon) material, for example, Mg C)-C
! If it is a refractory, use the same polarity 1 as E S1, which will be described later, and powder*. It is also possible to further promote the effect of preventing carbon from becoming liquefied from the adhesive surface. .

The A1 powder to be used has a high purity and a fine density, and is preferably 790% or more and 200/2 or less for a normal human body.

If the amount of A1 used is too high, there will be a large amount of A'l+,..., Qa remaining, and even if there is more than that, it will not contribute to the development of strength and will be unnecessary. If the amount is too small, the strength at high temperatures may not be sufficient, so the above-mentioned blending ratio is appropriate for A1.

○ Metallic silicon contributes to improving adhesive strength, although it is not as good as A1, and also helps refractories improve Mg, which is the objective of the present invention.
, to prevent the oxidation of carbon remaining on the adhesive surface from carbon or phenol resin in the case of O-0%, especially at high temperatures, and to suppress the water utilization reaction of A1 carbide, etc. It is believed that this is what brought about the fire.

Like A1, the S1 powder to be used is highly pure and finely powdered, preferably 9.0% or more and 200 mesh or less for a normal person.

If the amount of Sl used is too large, the corrosion resistance will be impaired, while if it is too small, the oxidation resistance and A
1. The prevention of water use by carbide becomes insufficient. , etc. Therefore, the above-mentioned mixing ratio is appropriate. . - It is of course possible to replace the A1 and Si powders used in the present invention with alloys of these, for example, those containing Al=Elil in common, within the range of their usage ratios.

○Mgo-based refractory powder reacts with metal aluminum to form Mgo-based refractory powder.
This is necessary in order to improve adhesive strength and provide corrosion resistance to the bonded surface by producing gO″A]1Osi′.

Mg0Ji to use! j powder is of high purity and fine powder,
Commonly known as 'MgO, it is desirable that the content is 95% or more and 200 meshes or less.

If the amount of MgO powder used is too large, the gap between the refractories to be bonded will widen due to the thermal expansion of MgO, and the adhesive strength will decrease.On the other hand, if the amount of MgO powder is too low, the gap between the refractories will be reduced. (MgO.A, 1zOa) is insufficient to fill the □, so the above-mentioned blending ratio is appropriate for MgO.

It should be noted that it is better to use Ai, SL, or Go quality powder, or the powder as mentioned above, because it is suitable for non-inventive adhesives and adhesives, and the gaps between the figures are less than 01τ. It is a desirable appearance. .

, the adhesive of the present invention has 1. These phenolic resins, A'l
, Si and i; MgO pickled rice powder essentially consists of
Other ingredients can be blended as long as they do not impair the purpose, but it is desirable that they be as small as possible, and usually they are limited to about 10 parts per 100 parts of phenol resin! ,
It is better to do so.

The adhesive of the present invention can be applied to the refractory surface by an appropriate method such as coating or spraying, and after joining the refractories together, heat treatment is performed to harden the phenolic resin, thereby making it possible to maintain contact at room temperature. do.

By using the adhesive of the present invention in this manner, even after the refractory is exposed to high temperatures under the conditions of use, it is possible to maintain the above-mentioned corrosion resistance and create an adhesive state with high trench strength. Ru.

In view of the purpose of the adhesive of the present invention, the refractory material is M
Although it is most suitable for adhering refractories containing gO as a main component, especially refractories made of MgO refractories and carbon, it can also be applied to adhesion of other refractories depending on the purpose.

As the refractory containing MgO as a main component, ordinary basic refractories containing MgO such as maknesia, makuro, chromag, dolomite, mag'dolo, and spinel (Mgo.AlzOs) are suitable.

The invention will be further explained below using a practical example.

EXAMPLE The formulation of the adhesive is as follows. (Parts by weight) These adhesives were made into a rectangular parallelepiped shape consisting of 35 x 35 x 140 ran.
When applying to the 35X35W surface of a large G0-C material, the adhesive gap is approximately 0.1 trrm), and after lightly butting and bonding, the temperature is increased from room temperature to 130℃ at a rate of 1℃/b.
Hold for minutes, 2℃/min from 130'C to 18.0℃
The temperature was raised at 180"C and held for 2 hours to heat-treat and harden the resin.

The adhesive strength (1
) and these refractories were heated at 800°C (I
The adhesive strength at room temperature was measured after being held at 400'C (m) for 5 hours, respectively, and the results were as follows. (KL1/crri) Example 2 The degree of adhesion of each sample, which was dried in the same manner as in Example 1 and then baked at 1200°C for 1 hour under an oxidizing atmosphere in an electric furnace, was determined by the following formula. A2. Ta.

Comparative Examples], 4 and 5 were separated during removal from the furnace, and Comparative Examples 2 and 3 were separated by twisting the two refractories by hand, but the ones to which the adhesive of the present invention was applied were only separated by twisting strongly. Met.

Among the sub-agents: 1) Akira Fukudai Akito Hagiwara Ryo

Claims (1)

[Scope of Claims] (1> An adhesive for Kingol resin thread refractories in which MgO refractory powder, metallic aluminum powder, and metallic silicon powder are present). (2) Claim 1, in which the amount of MgO refractory powder is 5 to 30 parts, the metal aluminum powder is 5 to 30 parts, and the metal silicon powder is 1 to 10 parts by weight, based on 100 parts of phenolic resin. Adhesives listed in section. (The adhesive according to claim 1 or 2, in which the 81 MgO refractory powder has a density of 200 mesh or less. (→ Claim 1 or 2, in which the A1 powder has a density of 200 mesh or less.) (5> 81 powder is 200 mesh or less. The adhesive according to claim 1 or 2. (6) The large resistant material between refractories containing IJgO as a main component. A refractory mainly composed of MgO, which is characterized by applying Mg, O-based refractory powder, metal aluminum, and metal silicon in a phenolic resin to the surface and bonding the refractories to each other. How to glue things together.