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2021

Magnesium aluminate spinel manufacturers take you to fully understand magnesium aluminate spinel

　　Magnesium aluminum spinel manufacturersTake you to fully understand what is magnesium aluminum spinel. Magnesium aluminate spinel has excellent properties, such as high melting point (2135), high hardness (16GPa), low thermal expansion, high corrosion resistance and excellent optical properties. Widely used in refractory materials, humidity sensors, transparent ceramic materials, anode materials, artificial flange materials and catalytic materials. In the field of refractory materials, magnesia-alumina spinel is mainly used for the preparation of magnesia-alumina spinel bricks, periclase-magnesia-alumina spinel bricks, periclase-carbon bricks and corundum-spinel castables, etc.

镁铝尖晶石

Magnesium aluminum spinel manufacturers research shows that additives can promote the formation of magnesium aluminum spinel, promote crystal transformation, reduce the preparation temperature. The additives used in the preparation of magnesium aluminate spinel are mainly rare earth oxides, fluorides, other oxides and composite additives. The addition amount, introduction mode and mechanism of different additives in the synthesis of magnesium are reviewed.

The Role of Oxides in the Synthesis of Magnesium Aluminate Spinel Raw Materials

Rare earth oxides have high melting point, high chemical activity and good corrosion resistance, which have certain influence on the synthesis of magnesium aluminate spinel.

The Role of Fluoride in the Synthesis of Magnesium Aluminate Spinel Raw Materials

Fluoride can promote magnesium to form aluminum spinel. Some experts found that F-doping in the crystal lattice replaced O2-, increased the vacancy concentration and diffusion of cations, and promoted the formation of spinel.Magnesium aluminum spinel manufacturersIt is shown that the addition of LiF decreases the spinel formation temperature and increases the spinel content by forming a liquid phase.

镁铝尖晶石

Synthesis Method of Magnesium Aluminate Spinel

Including electric melting, sintering, precipitation, sol-gel, hydrothermal synthesis, combustion synthesis, solution evaporation and supercritical, etc., of which electric melting, sintering is the main method.

1. Sintering method is to mix raw materials such as aluminum hydroxide and sintered alumina with magnesium carbonate, magnesium hydroxide and other magnesium-containing raw materials according to requirements, finely grind together, press into balls (blanks), and calcine at high temperature in a rotary kiln or shaft kiln above 1750 to synthesize magnesium aluminum spinel.

　　Magnesium aluminum spinel manufacturersThe spinel raw materials synthesized by sintering method contain impurities such as silica, calcium oxide and iron oxide.

2. The synthesis of magnesium aluminum spinel sand by electric fusion method can choose various purity raw materials containing magnesium and aluminum. The content of magnesium oxide in the spinel synthesis raw material is selected between 35% and 50%. Too high or too low MgO content is not conducive to the melting of synthetic sand, because of its high viscosity, the melt is difficult to pour, and the addition of chromium ore is conducive to the melting and pouring of the melt.

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Development of White Corundum in Metallurgical Industry Arc Wheel Dressing

RELATED INFORMATION

What is the difference between fused white corundum, dense corundum and brown corundum in refractory applications

2024-04-20

Fused white corundum, dense corundum (tabular corundum), brown corundum. These three are all aluminum raw materials. Fused white corundum is calcined alumina or industrial alumina as raw material, high temperature melting in the electric arc furnace, white, block material, crystal for the strip and rhombus, and often the skeleton of the crystal. Because the raw material is very pure, no chemical reaction occurs in the electric furnace operation, but the temperature of the molten liquid, the cooling rate, etc. have a great influence on the structure of the block. Fused white corundum, dense corundum (tabular corundum), brown corundum. These three are all aluminum raw materials. Aluminum content Dense corundum and white corundum reached 99%, brown corundum aluminum content: 95%. Price, dense corundum higher than white corundum White corundum is higher than brown corundum. So in the application of refractory materials, dense corundum is better than white corundum, brown corundum ranked third

Properties of Magnesium Aluminate Spinel

2024-04-20

Magnesium aluminate spinel is widely used in steel-making refractories due to its special properties of slag corrosion resistance, good thermal shock resistance and high strength at high temperature. High quality pre-fit The preparation of spinel provides a new raw material for the production of amorphous and shaped high purity refractories. The two main methods for the synthesis of spinel are sintering and electrofusion. Most spinel materials are made from high-purity synthetic alumina and chemical grade magnesia, That is, sintering in a shaft kiln and electromelting in an electric arc furnace. The advantage of sintering magnesium aluminate spinel is that the process is a continuous ceramization process, controlling the feed in the kiln. Velocity and uniform temperature distribution, resulting in a very uniform crystal size of 30-80 μm and low porosity (<3%) of the product. Electromelting production of magnesium aluminum spinel is a representative intermittent operation, large casting blocks need to extend the cooling time, the cooling of the casting block leads to microstructure. Uneven, due to faster cooling, the outer spinel crystals are smaller than the inner ones, and the low melting point impurities are concentrated in the center. Therefore, it is necessary Spinel raw materials are sorted and homogenized. Another advantage of using high-purity raw materials to produce aluminum magnesium spinel is the low impurity content in the aluminum magnesium spinel aggregate (MgO A1203>99%), especially SiO2 The low content makes it have good high temperature performance. Alumina-based aluminum magnesium spinel has no good performance as synthetic alumina-based aluminum magnesium spinel and can only be used Corrosion resistance and high temperature strength requirements are not high parts.

Magnesium aluminate spinel manufacturers take you to fully understand magnesium aluminate spinel

2021-05-19

Magnesium aluminate spinel has excellent properties, such as high melting point (2135), high hardness (16GPa), low thermal expansion, high corrosion resistance and excellent optical properties. Widely used in refractory materials, humidity sensors, transparent ceramic materials, anode materials, artificial flange materials and catalytic materials.

Introduction of magnesium aluminate spinel

2020-10-11

Bauxite-based sintered magnesium aluminate spinel uses high-quality bauxite with Al2O3 content of more than 76% and high-quality light burned magnesium powder with MgO content of more than 95%. In an ultra-high temperature tunnel kiln, it is sintered at a high temperature above 1800°C. Bauxite-based sintered magnesium aluminate spinel uses high-quality bauxite with Al2O3 content of more than 76% and high-quality light burned magnesium powder with MgO content of more than 95%. The chemical process is sintered at a high temperature above 1800°C in an ultra-high temperature tunnel kiln, with high volume density, high mineral phase content, good grain development and structure. Uniform, stable quality. Magnesium aluminate spinel has good corrosion resistance, corrosion, peeling ability, good slag resistance, abrasion resistance, thermal shock stability Good, high temperature resistance and other performance characteristics. It is the production of refractory products such as magnesium aluminum spinel bricks, ladle lining bricks, ladle castables and other refractory products for the high-temperature zone of cement rotary kilns. Ideal raw materials. Magnesium aluminate spinel is widely used in refractory materials, iron and steel smelting, cement rotary kiln and glass industrial kiln It has good erosion resistance, abrasion resistance and good thermal shock stability. Its main purpose: one is to replace the magnesium chrome sand manufacturing magnesium aluminum spinel brick Used in cement rotary kiln, not only to avoid chromium pollution, but also has good resistance to spalling; the second is used to make ladle castable, greatly improving the steel plate Lining resistance to erosion. It is widely used in steel-making refractory materials. Preparation of high-quality pre-synthesized spinel for amorphous and shaped high-purity refractories The production of new raw materials

Sanmenxia Shuntai fused corundum Co., Ltd.