As the name implies, the main component of carbon is carbon, which is used to increase carbon, but the quality of different carbon additives is also different. For example, there are graphite based, calcined petroleum coke based, calcined coal, natural graphite, waste electrode scrap, particle recycling, etc. The main component is carbon. It is very certain that the higher the carbon content, the lower the basic impurities (basic impurities generally refer to ash, volatile matter, etc.), and the sulfur and nitrogen content in the component, The role of sulfur is generally clear to everyone. Containing a certain amount of sulfur in cast iron can better improve the physical properties of castings. In recent years, nitrogen content has also been widely studied. If the nitrogen content is too high, nitrogen pores will occur, and if the nitrogen content is too low, the hardness of castings cannot be improved. There is a lot of ferrite, and generally, the nitrogen content of molten iron is controlled between 80ppm.