CN116332662A - A boron-free silicon dry material - Google Patents

Abstract

The invention discloses a boron-free siliceous dry material, which comprises the following raw materials in percentage by weight: 60 to 70 weight percent of silica with the granularity of 8 to 0mm, 5 to 15 weight percent of fused quartz with the granularity of 1 to 0.074mm, 10 to 20 weight percent of silica fine powder with the granularity of less than 0.074mm, 0.5 to 2 weight percent of fluoride with the granularity of less than 0.074mm and 0.5 to 3 weight percent of additive. According to the boron-free siliceous dry material, fluoride powder and an additive are added, so that the dry material can be well sintered under the condition of not adding boric anhydride or boric acid or other boron compounds, and the performance of the boron-containing siliceous dry material is achieved, and the boron-free siliceous dry material has the characteristics of low cost and long service life.

Description

A borosilicate-free dry material

technical field

The invention belongs to the field of refractory materials, and mainly relates to a boron-free silicon dry material.

Background technique

At present, the silicon dry-type materials used in domestic medium-frequency induction furnaces are mostly used as lining materials for cast steel, cast iron or other medium-frequency induction furnaces in non-ferrous fields because of their low price and long service life; the silicon dry-type materials used are mainly boric acid or Boron anhydride or other borates are used as sintering agents, and the main functions of adding boron or boron-containing compounds are as follows: (1) Liquid phase appears at a lower temperature to promote sintering; (2) Control the volume stability of the material to avoid Large cracks reduce the service life of materials; (3) Improve the sintering strength of furnace lining materials.

The role of boron in steel is (1) to improve the hardenability of steel. (2) Improve the high temperature strength of steel and strengthen the role of grain boundaries. However, the introduction of a very small amount of boron into some special steel grades will reduce the plasticity and toughness of the steel, especially the toughness will be greatly reduced. Therefore, when smelting these special steel types, it is necessary to require that the lining material of the induction furnace should not contain boron.

Contents of the invention

The purpose of the present invention is to solve the problem of boron increase in molten steel caused by boron-containing refractory lining material in induction furnace smelting special steel, and reduce the plasticity and toughness of steel, and propose a low-cost, long-life boron-free silicon dry material.

The present invention adopts following technical scheme for accomplishing the above object:

A boron-free silicon dry material, with silica and fused silica as the main raw materials, fluoride fine powder and additives added, the composition and weight percentage of the raw materials used are: silica with a particle size of 8-0mm 60-70wt%, 5-15 wt% of fused silica with a particle size of 1-0.074mm, 10-20wt% of fine silica powder with a particle size of less than 0.074mm, 0.5-2wt% of fluoride with a particle size of less than 0.045mm, and 0.5-3wt% of admixtures; Put it into a forced mixer and mix evenly to make a borosilicate-free dry material.

The chemical composition of the silica is SiO ₂ ≥98%, Al ₂ O ₃ <0.5%, Fe ₂ O ₃ <0.6%, CaO+MgO<0.4%; the chemical composition of the fused silica is SiO ₂ ≥99.8% .

The fluoride is calcium fluoride, magnesium fluoride, barium fluoride, zinc fluoride, strontium fluoride, aluminum fluoride, lanthanum fluoride, zirconium fluoride or one or more composites to promote sintering effect.

The admixture is calcium silicate, zirconium silicate, magnesium silicate, rutile, apatite, iron red and chromite ore, and it plays the role of auxiliary sintering.

Compared with the prior art, the innovation of the borosilicate-free dry material proposed by the present invention lies in:

(1) The dry siliceous material of the present invention does not contain boron or boron-containing compounds, and provides a low-cost, long-life furnace lining material for smelting special steel in intermediate frequency induction furnaces.

(2) The present invention promotes the sintering of silicon dry material by adding fluoride.

(3) The admixture selected in the present invention is to assist in promoting the sintering of the siliceous dry-form material, which can increase the strength of the dry-form material and control the expansion of the dry-form material.

Implementation

The following examples further illustrate the technical solutions of the present invention, but are not intended to limit the protection scope of the present invention.

Example

Silica 8～0mm 70%,

Fused quartz 1～0.074mm 12%,

Silica powder 0.053mm 13.2%,

Calcium fluoride 0.045mm 0.8%,

Magnesium fluoride 0.045mm 1.2%,

Zirconium silicate 0.013mm 1.6%,

Apatite 0.045mm 1.2%.

The boron-free silicon dry material produced according to the above ratio was taken out, and a part of the sample was taken out to make a (φ100*100)mm cylindrical sample. After burning in an electric furnace at 1600°C for 3 hours, the line change was measured to be 8.12%.

Example

Silica 8～0mm 70%,

Fused silica 1～0.074mm 15%,

Silica powder 0.053mm 11.1%,

Zinc fluoride 0.045mm 1%,

Barium fluoride 0.045mm 1%,

Calcium silicate 0.045mm 1.2%,

Iron red 0.013mm 0.7%.

The boron-free silicon dry material produced according to the above ratio was taken out, and a part of the sample was taken out to make a (φ100*100) mm cylindrical sample. After burning in an electric furnace at 1600°C for 3 hours, the line change was measured to be 6.79%.

Example

Silica 8～0mm 67%,

Fused silica 1～0.074mm 13%,

Silica powder 0.053mm 15.5%,

Barium fluoride 0.045mm 1.5%,

Zirconium silicate 0.013mm 2%,

Rutile 0.045mm 1%.

The boron-free silicon dry material produced according to the above ratio was taken out, and a part of the sample was taken out to make a (φ100*100) mm cylindrical sample. After burning in an electric furnace at 1600°C for 3 hours, the line change was measured to be 7.78%.

Example

Silica 8～0mm 70%,

Fused silica 1～0.074mm 10%,

Silica powder 0.053mm 16.5%,

Lanthanum fluoride 0.045mm 1.3%,

Aluminum fluoride 0.045mm 0.7%,

Chromite 0.045mm 1.5%.

The boron-free silicon dry material produced according to the above ratio was taken out, and a part of the sample was taken out to make a (φ100*100) mm cylindrical sample. After burning in an electric furnace at 1600°C for 3 hours, the line change was measured to be 6.21%.

Example

Silica 8～0mm 62%,

Fused silica 1～0.074mm 14%,

Silica powder 0.053mm 19.8%,

Zirconium fluoride 0.045mm 1.7%,

Apatite 0.045mm 1.5%,

Rutile 0.045mm 1%.

The boron-free silicon dry material produced according to the above ratio was taken out, and a part of the sample was taken out to make a (φ100*100) mm cylindrical sample. After burning in an electric furnace at 1600 ° C for 3 hours, the line change was measured to be 8.28%.

Claims (4)

1. A boron-free siliceous dry material is characterized in that: silica and fused quartz are taken as main raw materials, fluoride fine powder and an additive are added, and the adopted raw materials comprise the following components in percentage by weight: 60 to 70 weight percent of silica with the granularity of 8 to 0mm, 5 to 15 weight percent of fused quartz with the granularity of 1 to 0.074mm, 10 to 20 weight percent of silica fine powder with the granularity of less than 0.074mm, 0.5 to 2 weight percent of fluoride with the granularity of less than 0.045mm and 0.5 to 3 weight percent of additive; the raw materials are sequentially put into a forced mixer to be mixed uniformly, and the boron-free siliceous dry material can be prepared.

2. The boron-free siliceous dry mix of claim 1, wherein: the chemical component of the silica in the raw materials is SiO ₂ ≥98%，Al ₂ O ₃ ＜0.5%，Fe ₂ O ₃ Less than 0.6 percent, caO+MgO less than 0.4 percent; the chemical composition of the fused silica is SiO ₂ ≥99.8%。

3. The boron-free siliceous dry mix of claim 1, wherein: the fluoride is one or more of calcium fluoride, magnesium fluoride, barium fluoride, zinc fluoride, strontium fluoride, aluminum fluoride, lanthanum fluoride and zirconium fluoride.

4. The boron-free siliceous dry mix of claim 1, wherein: the additive is one or more of calcium silicate, zirconium silicate, magnesium silicate, rutile, apatite, iron oxide red and chromite.