Magnesia chrome brick is a refractory product composed of magnesium oxide (MgO) and chromium oxide (Cr2O3) as the main components, and periclase and spinel as the main mineral components. It belongs to alkaline refractory products. Rongsheng Magnesia Chrome Refractory Bricks have high refractoriness, high-temperature strength, strong resistance to alkaline slag erosion, excellent thermal stability, and certain adaptability to acid slag. The firing process of magnesia chrome brick is roughly similar to that of magnesia brick. Magnesia-chrome bricks are generally fired with light-burned magnesia and imported chrome ore. It is also called ordinary sintered magnesia chrome brick, or magnesia chrome brick for short.
The Characteristics of Magnesia Chrome Bricks
- The refractoriness is greater than 2000°C.
- The softening temperature under load is generally above 1550°C.
- Good volume stability at high temperatures.
- It has better resistance to rapid cold and rapid heat.
Magnesia Chrome Refractory Brick Applications
Because Magnesia Chrome Refractory Bricks have the advantages of high refractoriness, high-temperature strength, strong resistance to alkaline slag erosion, and strong thermal shock resistance. Magnesia chrome bricks are mostly used in cement rotary kilns, glass kiln regenerators, steelmaking furnace linings, permanent layers of refining ladle, non-ferrous metallurgy furnaces, lime kilns, iron mixers, and refractory high-temperature furnace linings. It is also used in open-hearth furnace top, electric furnace top, outside refining furnace, and various non-ferrous metal smelting furnaces.
Magnesia Chrome Refractory Bricks Used in the Non-Ferrous Metal Industry
The refractory bricks used in the non-ferrous metal industry mainly include Magnesia Chrome Refractory Bricks, silicon carbide refractory bricks, corundum refractory bricks, and high alumina refractory bricks. Among them, magnesia chrome refractory bricks are widely used in copper smelting, nickel smelting, and lead smelting industries. The characteristics of these three types of metal smelting are:
- The flue gas contains a lot of SO2 gas.
- The melt contains not only oxides, metals, but also many sulfides. The melt melting temperature is relatively low, but the melt fluidity is better.
- The slag is FeO-SiO2 slag, and the amount of slag is very large.
- The temperature in the furnace fluctuates greatly, and the melt erodes the refractory bricks seriously.
Magnesia Chrome Refractory Bricks have a strong resistance to iron-silicon slag erosion and SO2 erosion, and also have good resistance to melt erosion. It is currently the most used refractory brick for smelting three kinds of metals.
Buy Magnesia Chrome Bricks For Non-Ferrous Metal Industry!
There are many types and varieties of magnesia-chrome refractory bricks. According to its combination method, it can be divided into ordinary magnesia chrome bricks, directly combined magnesia chrome bricks, recombined magnesia chrome bricks, semi-recombined magnesia chrome bricks, and so on.
(1) Ordinary magnesia chrome brick, that is silicate combined magnesia chrome brick. The impurity content of CaO and SiO2 is relatively high, and the sintering temperature is 1550℃, which is directly made of magnesia and chromium ore. The microstructure of this type of refractory brick shows that the granular chrome ore is wrapped by the finely dispersed magnesia binder, and there is also a silicate filler with a lower melting point between the crystal grains. As a result, it has low high-temperature strength and poor slag resistance. With the development of non-ferrous metal pyrometallurgical smelting technology, the brick has been completely eliminated.
(2) Directly combined magnesia-chrome bricks, made of purer magnesia and chrome ore concentrate. The impurity content of SiO2 and CaO in the brick is low, and the firing temperature used is above 1700℃. The microstructure of the brick shows a high direct bonding rate of high melting point minerals. High-temperature performance, erosion resistance, and erosion resistance are obviously better than ordinary magnesia chrome bricks.
(3) Re-combined magnesia chrome brick, it is a magnesia chrome brick made of fused magnesia chrome material. The content of impurities in the raw materials is less, and the firing temperature is also above 1750°C. The microstructure morphology of the brick shows that the spinel component distribution is relatively uniform in the spinel, which effectively improves the erosion resistance.
(4) Semi-recombined magnesia chrome bricks are magnesia chrome bricks made of synthetic raw materials as granules and fine powder of chromium concentrate and magnesia. The firing temperature is above 1700°C. The microstructure morphology of the brick shows that the crystals are mainly directly bonded together, and it has good thermal shock resistance.
Fused Cast Magnesia Chrome Brick
The production process of fused-cast magnesia chrome bricks is completely different from conventional sintered refractory production methods. It uses magnesia and chrome ore to add a certain amount of additives and mixed ingredients, melts in an electric arc furnace, and pours into the model. Controlled cooling and annealing to produce master bricks. After cutting, grinding, drilling, and cold processing, the required brick shape is produced.
Fused cast magnesia chrome bricks have unique advantages over the damage mechanism of slag penetration. Because it is a dense frit made by melting, pouring, and overall cooling. The molten slag can only corrode on the surface of the brick, and it is impossible to penetrate, which has been verified by the cross-section identification of the fused cast magnesia chrome brick after use. Therefore, although the production of Fused Rebonded Magnesia Chrome Bricks is difficult and expensive, it still retains the irreplaceable advantage of other refractory materials in key parts of non-ferrous smelting furnaces in technologically developed countries.
Rongsheng refractory brick manufacturer
Rongsheng is an experienced refractory brick manufacturer. Rongsheng refractory manufacturer has served customers in more than 60 countries, for example, India, Pakistan, Kuwait, South Africa, Malaysia, Vietnam, Netherlands, Philippines, Singapore, Egypt, Russia, etc. Whether it is the quality of refractory material products or customer service, Rongsheng has received good reviews in the industry. Rongsheng’s experienced technical team provides technical support for the refractory products required by customers. Rongsheng’s advanced production workshop has laid a solid foundation for the quality of refractory materials. For more information about magnesia chrome refractory bricks, please contact us. If possible, please leave your specific needs and the working conditions of the refractory bricks you need on the form on our website. We will get back to you as soon as possible.