Applications of Silicon Carbide
Silicon Carbide (SiC) is a compound composed of carbon and silicon atoms, known for its exceptional hardness, excellent thermal stability, and corrosion resistance. In terms of weight composition, SiC contains approximately 70% silicon and 30% carbon. SiC was primarily used as an abrasive due to its high hardness, It found applications in refractory materials and furnace linings because of its stability at high temperatures and resistance to oxidation.
In the casting industry, SiC's unique physical and chemical properties make it widely used as a deoxidizer and carbon additive for iron alloys. When added to gray cast iron, ductile iron, or malleable cast iron, SiC can act as a deoxidizer at lower temperatures (<1620°C) by reducing unstable oxides such as FeO and MnO. At higher temperatures (>1620°C), it functions primarily as a carbon additive with a carbon recovery rate approaching 100%. This characteristic makes SiC an essential additive in coreless induction furnaces for iron smelting, particularly in the United States, where about 95% of coreless induction furnaces use SiC as the primary silicon source.
The addition of SiC not only improves the purity of the melt and reduces surface defects on castings but also increases the melting point of slag by lowering its FeO content, thereby reducing its fluidity and minimizing the impact of high FeO and MnO slag on casting quality. Additionally, SiC helps reduce FeO-SiO2 inclusions in the iron, which are major factors causing poor flowability, increased shrinkage porosity, and white mouth formation, especially in ductile iron.
In the production of ductile iron, SiC is also used as a pre-inoculant to optimize pure magnesium treatment, reducing the tendency for shrinkage and carbide formation. Studies have shown that adding an appropriate amount of SiC (about 2 kg/t) to the treatment package can effectively address these issues.
For gray iron and compacted graphite iron, the application of SiC brings significant metallurgical benefits, including reduced slag formation and fluidity, increased eutectic cell count, reduced white mouth tendency, and extended aging time. Based on these advantages, many domestic and international foundries tend to add a certain proportion of SiC to their charge materials, with recommended addition rates of 10-15 kg/t for gray iron and 5-10 kg/t for compacted graphite iron.
In summary, SiC's multifunctionality demonstrates great potential in improving the quality and production efficiency of cast iron, especially in meeting increasingly stringent quality standards and intense market competition. As high-magnesium alloy core wire technology for producing ductile iron continues to advance, the role of SiC as a carbon additive, silicon additive, and pre-inoculant will become even more prominent, making it a key material for the transformation and upgrading of China's casting industry.
Applications of Graphitized Carburizer
Graphitized Carburizer is a commonly used material in casting and ironmaking, primarily to increase the carbon content in molten iron, thereby enhancing the performance of castings. High-quality Graphitized Carburizer not only ensures the quality of castings but also improves production efficiency and reduces costs.
Practical Applications of Graphitized Carburizer
1. Scrap Steel and Graphitized Carburizer Process: In the production of high-strength gray cast iron castings, using a process that combines scrap steel with Graphitized Carburizer can significantly improve the purity of the molten iron, resulting in superior casting performance.
2. Electric Furnace Smelting: In electric furnace smelting, the use of Graphitized Carburizer is particularly effective, as it not only increases the carbon content in the molten iron but also promotes the formation of graphite nuclei and reduces the oxidation of the molten iron.
3. Addition Methods: Graphitized Carburizer can be added to the electric furnace along with scrap steel and other charge materials or in small quantities on the surface of the molten iron. However, large-scale additions should be avoided to prevent excessive oxidation and ensure effective carbon addition.
4. Selection of Graphitized Carburizer: Different types of cast iron (such as gray iron, ductile iron, and compacted graphite iron) have different carbon content requirements, so the type and amount of Graphitized Carburizer should be selected based on actual needs.
Impact on Precision Casting of Graphitized Carburizer
1. Improved Casting Quality: Proper use of Graphitized Carburizer can enhance the density and strength of castings, reducing defects such as porosity and shrinkage.
2. Promotion of Graphitization: Graphitized Carburizer helps form graphite in the molten iron, improving the wear resistance and machinability of castings.
3. Cost Control: The use of Graphitized Carburizer can increase the use of scrap steel and reduce the consumption of pig iron, thereby lowering production costs.
4. Environmental Friendliness: Compared to traditional carbon addition methods, the use of Graphitized Carburizer can reduce harmful gas emissions, aligning with modern industrial environmental requirements.
In conclusion, the application of Graphitized Carburizer in the casting industry not only significantly improves the quality and performance of castings but also helps foundries achieve energy conservation and emission reduction goals, meeting sustainable development requirements. As casting technology continues to advance, the application scope and technical level of Graphitized Carburizer will continue to expand, offering a broad and promising future in the casting field.
LSFerroalloy Silicon Carbide and Graphitized Carburizer
LSFerroalloy is a high-tech enterprise specializing in the production of Silicon Carbide and Graphitized Carburizer. The company boasts advanced production equipment and a strict quality management system, dedicated to providing customers with high-quality silicon carbide and Graphitized Carburizer products. LSFerroalloy products are widely used in the casting, steel, and refractory materials industries, earning high praise from clients. The company adheres to the business philosophy of "innovation-driven and quality-first," continuously developing new products and enhancing technical capabilities to contribute to industry development.