The process development of pretreatment agent can be effectively divided into two stages to a certain extent, namely, traditional pretreatment process and modern pretreatment process. In the process of operation, the traditional pretreatment process is usually to effectively add its graphite carburizing agent or SiC into the furnace, so that the new core of these substances can be effectively used to effectively improve the metallurgical quality of molten iron.
Modern pretreatment technology can effectively control w (o) in molten iron at a low level by adding pretreatment agent before inoculation. Through tests and comparison, some enterprises producing high-end castings (cylinder block and cylinder head) show that their use effect is obviously better than that of metallurgical grade silicon carbide. Therefore, the pretreatment agent based on SiC is favored and applied by foundry factories.
Advantages of using pretreatment agent:
1. Reduce the amount of spheroidizing agent by about 10%.
2. Improve the absorption rate of Mg.
3. Increase the number of graphite balls per unit area
4. Reduce the tendency of shrinkage porosity and slag inclusion.