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Magnesia-chrome brick is divided into ordinary magnesia-chrome brick, direct combination of magnesia-chrome brick, half-combined magnesia-chrome brick, fused magnesia-chrome brick, fused semi-combined magnesia-chrome brick, The difference between magnesia-chrome brick lies in the following: 1: Purity of magnesia sand (raw material) 2: Sintering temperature, Ordinary magnesia-chrome brick Sintering temperature 1550 ℃ ~ 1600 ℃, Direct magnesia-chrome brick Sintering temperature above 1700 ℃, Above, the microstructure of magnesia-chrome brick changes, periclase and chromium ore directly combined, so called direct combination of magnesia-chrome brick. Magnesium chrome bricks directly in all aspects of performance are better than ordinary magnesia-chrome brick.?