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The types of magnesia-chrome brick products and their performance and application analysis

2020-12-24 09:22:49

(1) With the increase in the amount and size of secondary spinel magnesia chrome brick manufacturers in the brick, for example, the volume fraction of secondary spinel in the direct combined magnesia chrome brick reaches 6% and the secondary spinel in the combined magnesia chrome brick The high temperature flexural strength reaches a high value when the volume fraction of spinel reaches 8%. The high temperature flexural strength is an important indicator to measure the high temperature wear resistance of MgO-Cr2O3 bricks, and the high temperature wear resistance can reflect the important indicators of resistance to high temperature molten steel and slag erosion. Therefore, the direct combination of the large amount of secondary spinel, Recombination (semi-recombination) magnesia-chrome bricks will inevitably improve the corrosion resistance of molten steel and molten slag: ladle magnesia-carbon bricks

(2) There is a large amount of secondary spinel in the combined magnesia chrome brick that prevents the erosion of slag, so the slag resistance is high:

(3) Improve the fineness of the fine powder in the ingredients (for example, when the specific surface area of the fine powder reaches 5m2/g), combined with the thermal shock resistance of the magnesia chrome brick is significantly improved. In a word, using optimized raw materials, ultra-high temperature firing and other brick-making processes to increase the amount of secondary spinel in the brick, a refined steel tank slag line with high comprehensive performance can be obtained by direct bonding and recombination (semi-recombination) Typical properties of several directly bonded magnesia chrome bricks of a company in magnesia chrome bricks


The addition of alumina to magnesia-chromium refractories has different effects depending on the raw materials used. The raw materials contain more impurity components such as CaO and SiO2, and the addition of appropriate alumina components can promote the sintering of magnesia-chromium refractories, and the brick structure will become denser. This is because alumina can form low-melting substances with the calcium silicon and other components present in the bricks, and the formation of these low-melting substances accelerates the progress of sintering and the process of densification.

However, due to the different content of CaO and SiO2 in the raw materials, the influence of the crystal structure of periclase in the raw materials, resulting in differences in the content and diffusion of CaO and SiO2 in the brick body; when the amount of CaO and SiO2 diffused to the boundary is insufficient When meeting the reaction rate of alumina, the remaining alumina will react with MgO in the periclase crystal as follows:


That is, spinel is generated at the grain boundary and other positions in the brick body. Because the volume and density of the reactant MgO, Al2O3 and the product magnesia-aluminum spinel are relatively large, the spinel generation is accompanied by a large volume expansion. This hinders the sintering reaction of the magnesia-chrome brick body to a large extent, the pores in the brick body increase and the strength decreases. Magnesia Chrome Brick

In other words, adding alumina to the magnesia chromium refractory material needs to consider the CaO and SiO2 components in the raw materials, and appropriately add alumina; if most of Al2O3 is added, it can react with the calcium silicate components in the brick body to form a low melting phase, and It presents a continuous distribution in the brick body. At this time, because the amount of liquid phase increases during the sintering process, it can promote the material transmission during the sintering process, promote the sintering of the brick body, and improve the density of the product; on the contrary, if CaO, The content of SiO2 is too low to meet the conditions of consuming Al2O3 to form a liquid phase. At this time, Al2O3 will react with the MgO component in the brick body to form spinel, and the volume expansion caused by the formation of spinel cannot be well alleviated. , The density of magnesia-chromium products will decrease, and the compressive strength at room temperature will be affected.



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Yingkou Nanlou Economic Development Zone Chengshen

Contact: Manager Lin Electric Furnace Magnesia Carbon Brick

Mobile phone: 182-4265-7979

Website: www.csnh10.com

Address: Chenjia Village, Nanlou Economic Development Zone, Yingkou City, Liaoning Province

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