As different binding material, SIC's performance, working condition and life are all different. Classified as follow,
1.Binding with clay
In silicon carbide refractories, clay is the most common, the lowest price and the most simple process.At present, in China's ceramic industry, clay is used in a large amount of silicon carbide kiln. Aluminum, oxygen and silicon carbide in the clay react in 1120 ~ 1150 ℃
The clay amount in the product is generally not more than 15%, the fine powder in the ingredients should not be too much, otherwise it is easy to oxidize.The content of silicon carbide is between 50% and 93%.It is used to make saggar, padded and NC-G.
2.Binding with SIO2
Add about 10% of SiO2 (micropowder and quartz powder) in silicon carbide.The silicon carbide particles are oxidized to generate SiO2 films and combine the silicon carbide particles during sintering process.
Because its raw material purity is high, miscellaneous quality is little.Can be used in the above 1200 ℃ high oxygen atmosphere.Generally used for making ceiling boards and supports.
3.Binding with mullite
Mullite (5% ~ 8%) and silicon carbide as raw material, pulp or dextrin as binder, formed by 1380 ℃ after firing, the mullite combined with silicon carbide is firmly combined.
The product has good performance, thermal shock resistance and good oxidation resistance compare with clay and SIO binding. At present, the application of ceramic kiln.
4.Reaction and sintering
Add silicon metal powder and carbon in silicon carbide (graphite, carbon black, etc.) at 1450 ℃ is buried carbon burning, silicon powder and the carbon reaction type low temperature beta SiC, combine the original silicon carbide particles.
Because the products generally contain free silicon 8% ~ 15% and small amounts of free carbon, so use temperature below 1400 ℃.Its thermal conductivity and impact resistance are good, but the strength, hardness and corrosion resistance are poor.Reaction sintered silicon carbide products are almost invariable before and after sintering, so they can be processed into any shape and size, especially for large scale and complex shapes.
5.Binding with silicon nitride
The high temperature performance of silicon nitride can be used as the binding agent of silicon carbide products, and silicon nitride and silicon carbide products are the latest high-tech silicon carbide refractory materials.
Silicon nitride combined with silicon carbide products with good physical and chemical properties, high temperature performance, the use of temperature of 1500 ℃, the abrasive, metallurgy and daily, electronic ceramics and other industries widely used.As a kiln has broad prospects.
6.Bingding with Silicon oxynitride
Its properties are close to silicon nitride and silicon carbide products, and its antioxidant properties are superior.The nitric oxide silicon oxide distributed by the reaction is distributed around the silicon carbide particles and binds it closely to make the silicon carbide maintain excellent oxidation resistance.
| Grade | SiC% | F.C% | Fe2O3% |
| ≥ | ≤ | ||
| SiC98 | 98.0 | 0.3 | 0.3 |
| SiC97 | 97.1 | 0.5 | 0.5 |
| SiC96 | 96.1 | 0.6 | 0.6 |
| SiC95 | 95.5-96.8 | 1 | 0.7 |
| SiC94 | 94.5-95.8 | 1.5 | 0.8 |
| SiC93 | 93.5-94.8 | 2 | 1 |
| SiC92 | 92.5-93.8 | 2.5 | 1.2 |
| SiC90 | 91.0-92.5 | 3 | 1.5 |
| SiC89 | 90.5-92.0 | 3.5 | 2 |
| SiC88 | 89.5-91.0 | 4 | 2.5 |
Advantages
1.High strength
2.High thermal conductivity
3.Good shock resistance
4.Oxidation resistance
5.Wear resistance and corrosion resistance
Applications
1. Abrasive, Grinding, Metallurgy, Refractory,Ceramics, Petroleum,Chemical,Microelectronics,Automobile and Aerospace and so on.
2. Ceramics firing kiln, and vertical cylinder distillation furnaces for bismuth and zinc smelting industries.
3. Silicon carbide ceramic products such as silicon carbide bricks, aluminum electrolytic tank linings, crucibles, and small kiln refractories.
Packing
