What are the differences between magnesium chrome bricks, such as direct bonding, re bonding, semi bonding, CO sintering and chemical bonding? Hope expert advice..
The fine powder compacts after calcination produced by magnesia - chrome ore grinding method, brick with magnesia coarse particles, are effective measures to eliminate the effect of loose. Compared with the common magnesia chrome brick, the magnesia chrome brick made by this method has lower porosity, higher compressive strength, higher softening temperature and higher flexural strength. Compacts with chrome magnesite powder, magnesia chrome brick by synthetic magnesia chrome sand made of high-temperature calcination, slag resistance and high temperature strength are better than other magnesite chrome brick. In addition, magnesite brick and electric arc furnace melting magnesium chromium material by direct casting (see Figure microstructure, color), fused magnesia chrome brick material produced by the process of melting particles combined with magnesia chrome brick etc..
Direct bonded magnesia chrome brickThe loose effect caused by the expansion of spinel when the oxide of magnesia brick is directly reacted with the oxide of iron can also be used to make magnesia chromite brick with synthetic common sintered material. In addition, there are non burned magnesia chrome bricks, for example, non burned magnesia chrome bricks combined with inorganic magnesium salt solutions. The unfired magnesia chrome brick has the advantages of simple production process, low cost and good thermal stability, but the strength of the high temperature is far less than that of the burnt brick. In the late 50s, a so-called "direct bonding" magnesia chrome brick was developed. The characteristics of this brick raw material is pure, high firing temperature, periclase and spinel phase with high temperature directly, silicate and other low melting point phase for island distribution, therefore, significantly improve the high temperature strength and slag resistance of brick.
The process of firing magnesia chrome bricks is roughly the same as that of magnesia bricks. In order to eliminate the brick during firing, due to MgO and Cr2O3, Al2O3
