High-Purity Magnesium-Aluminum Spinel Grades: Sma-66, Sma-78 And Sma-90. Sintered Spinel Product Series
- Sintered magnesium aluminate spinel
- Magnesia spinel clinker
- synthesize spinel
Short Description
Features
• Junsheng high-purity magnesium-aluminum spinel has the following characteristics:
• High refractory resistance;
• Good high temperature volume stability;
• Excellent resistance to alkaline slag corrosion and penetration;
• Good thermal shock stability.
|
ITEM |
UNIT |
BRANDS |
||||
|
|
|
SMA-78 |
SMA-66 |
SMA-50 |
SMA90 |
|
| Chemical composition | Al2O3 | % | 74-82 | 64-69 | 48-53 | 88-93 |
| MgO | % | 20-24 | 30-35 | 46-50 | 7-10 | |
| CaO | % | 0.45max | 0.50max | 0.65max | 0.40max | |
| Fe2O3 | % | 0.25max | 0.3max | 0.40max | 0.20max | |
| SiO2 | % | 0.25max | 0.35max | 0.45max | 0.25max | |
| NaO2 | % | 0.35max | 0.20max | 0.25max | 0.35max | |
| Bulk Density g/cm3 | 3.3min | 3.2min | 3.2min |
3.3min |
||
| Absorbing water rate% | 1 max | 1 max | 1 max | 1 max | ||
| Porosity rate % | 3 max | 3 max | 3 max | 3 max | ||
‘S’ ----sintered ; F-----fused ; M------magnesia; A----alumina; B----bauxite
Spinel minerals have an important influence on the high-temperature properties of refractory materials. For example, due to the small thermal expansion coefficient of spinel (α=8.9x10-*/℃ at 100~900℃), spinel is used as a binding agent ( Or called cementing phase, matrix), magnesia-alumina bricks with periclase as the main crystal phase, when the temperature changes sharply, the internal stress generated is small, and the bricks are not easy to break, thus the thermal stability of the bricks can be improved (magnesia-alumina bricks The thermal stability is 50~150 times).
In addition, because spinel has good properties such as high hardness, stable chemical properties, and high melting point, and is very resistant to corrosion by various melts at high temperatures, the presence of spinel minerals in products has improved the High temperature performance of the product.
The main reason why the high-temperature load softening temperature of magnesia-alumina bricks (starting point is not less than 1550-1580℃) is higher than that of magnesia bricks (starting point is below 1550℃) is that the matrix composition is different.
To sum up, spinels are excellent materials in terms of melting point, thermal expansion, hardness, etc., with relatively stable chemical properties, strong resistance to alkaline slag erosion, and resistance to molten metal erosion .Comparison of properties of spinel and other oxides.
Basic Information
Junsheng high-purity magnesium-aluminum spinel system uses high-purity alumina and high-purity magnesium oxide as raw materials, and is sintered at high temperature. According to different chemical compositions, it is divided into three grades: SMA-66, SMA-78 and SMA-90. Product Series.
Junsheng high-purity magnesia-aluminum spinel has extremely low impurity content and excellent high-temperature performance. High-purity spinel is suitable for prefabricated parts such as breathable bricks, seat bricks, ladles, electric furnace top covers, refractory materials for rotary kilns, and refractory materials for smelting alloys. products, as well as spinel-containing shaping sets.
Products can help improve the slag corrosion resistance of refractory materials, and solve the problem of material cracking caused by adding magnesium raw materials.
