The fused half-recombined magnesia-chrome brick refers to a refractory product fired from a portion of fused magnesia chrome. The main mineral composition of fused semi-recombined magnesia chrome bricks is periclase, spinel and a small amount of silicate. The particles are in an opaque structure, the spinel in the periclase crystal is completely developed, and the matrix portion is a turbid structure. The crystals are directly combined with periclase-periclite or periclase-spinel, and the silicate phase exists in the isolated state between the grains. The thermal shock resistance of the electrofused half-recombined magnesia-chrome brick is better than that. Electrofusion directly combines magnesia-chrome bricks.

Manufacturing process:
The fused magnesia-chromium material is used as a granule, a part of chrome ore and magnesia or a sintered synthetic magnesium-chromium material is added as a fine powder, and bricks are prepared according to a conventional process. The fused magnesia should be smelted in a weak oxidizing atmosphere. There should be no more reducing phases in the material, and metal iron and chromium should be avoided. The magnesia and chromite used as fine powder must be ground together, and the fineness should be guaranteed. Less than 0.088mm accounts for more than 95%; it is formed by high-tonnage brick press, and the brick density is greater than 3.2g/cm3. After the brick is dried, the moisture in the kiln is less than 1.0%. The product is fired in a tunnel kiln, and the firing temperature is above 1750 ° C, and a weak oxidizing atmosphere is maintained in the kiln.

Features and applications:
The fused half-recombined magnesia-chrome brick is compact, low in porosity, high in high-temperature strength, and superior in thermal shock resistance to electro-fusion combined with magnesia-chromium brick, and has strong resistance to slag corrosion. It can be used in the vulnerable parts of steelmaking electric furnace, RH, DH vacuum degassing device, secondary refining slag line of VOD, LF, ASEA-SKF, AOD and other serious erosion parts, copper converter converter tuyere area, cement rotary kiln firing zone And glass furnace regenerator. The fused half-recombined magnesia-chrome brick has lower cost and better thermal shock resistance than the fused-fused magnesia chrome brick with equivalent composition, and can replace the electro-fusion and magnesium chrome brick in a certain range.

Technical Indicators