Have good slag resistance and high temperature performance and the high combination rate,good thermal shock resistance.
1. Magnesia 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.
Magnesia chrome brick is also called magnesium silicate bonded chrome bricks and magnesia chrome bricks for short.
The production process of ordinary Magnesia chrome brick is simple and its price is cheap and that are widely used in rotary cement kiln.
Directly bonded magnesia 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 .
Direct combination magnesia 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.
2. Applications:
The mainly used for cement rotary kiln, lime kiln and refractory roasting kiln.
3. Chemical and Physical Index
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