Magnesium chrome brick is generally produced by sintered magnesia (MgO content is between 89 ~ 92) and chromium-refractory materials. Refractory grains are combined by silicate due to its impurities. The commonly known as magnesium chrome bricks in China is generally refers to the ordinary burned magnesium chrome bricks. It is also called magnesium silicate bonded chrome bricks and magnesium chrome bricks for short.
The production process of ordinary Magnesium chrome brick is simple and its price is cheap and that are widely used in rotary cement kiln.
Directly bonded magnesium chrome brick is the product that is produced by chrome ore with lower impurity and magnesia with high purity that is sintering in a temperature above 1700 ℃. The refractory grains are contacted directly. The direct combination as a micro-structure parameter is not only used in magnesium chrome materials but also in other materials.
The main difference of production process between direct combination magnesium chrome brick and magnesium chrome brick is that the first is used pure raw material and sintered in higher temperature.
Direct combination magnesium chrome bricks have good slag resistance and high temperature performance due to its less impurity in the chemical composition and the high combination rate between refractory grains. Its thermal shock resistance is excellent and can reach 6 to 10 times from 1100 ℃ to cold water.

Index	Standard	Semi-direct bonded	direct bonded
MgO/%≥	55~60	≥65	≥70	≥70	≥75	≥80
Cr2O3/%≤	8~12	8~13	≥9	≥9	≥6	≥4
SiO2/%	≤5.5	≤4.0	≤3.0	≤2.8	≤2.8	≤2.5
volume density ./kg.m-3	2850	2900	≥2980	≥2980	≥2950	≥2930
Apparent porosity%≤	23~24	20~22	≤19	≤19	≤18	≤18
Compress strength,/MPa≥	≥20	≥35	≥40	≥40	≥40	≥40
refractoriness under load, ℃≥ T0.6      T2	≥1530	≥1550   ≥1650	≥1580      ≥1700	≥1600    ≥1700	≥1600    ≥1700	≥1600     ≥1700
Linear expansivity /% (1000℃)	1.0	1.1	1.01	1.03	1.05	1.05
Thermal shock resistance (1100℃-Water cold)	≥3	≥4	≥4	≥4	≥4	≥4

Welcome to contact us.Our email is info at oreworld dot com

website:http://www.oreworld.com