Poor quality carburizers can directly affect the quality of finished products!

Why do we say that when choosing materials, we must choose high-quality ones? High quality carburetors are more conducive to the implementation of cast iron technology, while quality problematic carburetors can affect the quality of the product. During the casting process, carbon containing substances added to supplement the carbon content required for the molten iron are called carburizers. It plays a crucial role in the smelting process, so the quality of the carbon additive directly determines the quality of the product.
For example, in terms of nitrogen content, due to the low titanium content in molten iron, titanium cannot consume a large amount of nitrogen, which makes castings prone to nitrogen porosity, cracks, or related defects caused by high nitrogen content in molten iron with a nitrogen content of 120ppm. Therefore, the selection of carburizer is crucial, as poor quality of carburizer can cause significant losses. When using synthetic iron smelting, it is more crucial to choose low sulfur and low nitrogen carbonization agents. Untreated ordinary coal and petroleum coke have a high content, generally exceeding 8000ppm (0.8%).
The nitrogen content of petroleum coke after high-temperature treatment is usually less than 1200ppm, but different control measures taken by suppliers to produce carburizers and calcination temperatures result in different nitrogen contents for various types. So when choosing a carbonization agent, in order to ensure quality, it should be selected after graphite treatment at a high temperature of 2700 ℃ for more than 72 hours. The nitrogen content is often high and does not exceed 300ppm.
Yichen Carbon Enhancer
It can be said that the quality of the carbon additive directly affects the quality of the product. In addition, high nitrogen content carbon additives are prone to nitrogen porosity defects. When smelting gray cast iron and ductile iron, nitrogen porosity defects may occur, but the probability of ductile iron is lower than that of gray cast iron. It is estimated that this is because during the spheroidization process, rare earth elements and other oxygen and gas removal elements are added, allowing gases to precipitate and evaporate during the rolling of the molten iron spheroidization.
Of course, various carbonization agents in China are still gradually adapting, especially high nitrogen carbonization agents that involve casting costs are still widely used. Carbon additive suppliers will need to gradually accumulate experience in the future. Recommend suitable carburizers for casting enterprises.
Truly benefiting casting enterprises in terms of quality and cost. Adding a carbon additive with poor graphitization to molten iron results in low absorption rate (only 60-80%), slow absorption rate, and residue generated in the furnace. It is easy to exceed the nitrogen content of hot metal and produce pore like nitrogen.
The method of adding carburizer is to add a large amount of carburizer during the synthesis of cast iron. It can be added together with scrap steel in the early or middle stage of electric furnace smelting, and silicon carbide pretreatment agent can be added at the same time. Plays a preprocessing role and increases the graphite nucleation core. If carbon addition is carried out after the molten iron is melted, it is necessary to add low-carbon agents with low sulfur and nitrogen content, and the amount added should not be too much, not exceeding 0.2%, to avoid excessive thickness of the surface layer. Affects absorption speed.