During the smelting and storage process, ferrosilicon is prone to two major quality problems: segregation and pulverization. The segregation phenomenon is mainly manifested as compositional stratification during alloy solidification, where the upper layer is rich in silicon and the lower layer is rich in iron. This is closely related to casting thickness, cooling rate, and alloy composition, with 75% ferrosilicon being particularly evident.
To control segregation, it is necessary to control the thickness of 75% silicon iron ingots within 100mm and 45% silicon iron within 150mm, while appropriately reducing the casting temperature and accelerating the cooling rate. The pulverization problem is even more complex, mainly due to the formation of unstable phases by impurity elements in the alloy during solidification, followed by internal stress and crack formation during phase transformation. In a humid environment, it reacts with moisture to produce gas, ultimately leading to alloy fracture. Among them, impurities such as phosphorus and aluminum have the most significant impact, and alloys with 50% -60% silicon content have the greatest tendency to pulverize.
In production, it is necessary to start with raw material control, reduce the content of harmful elements such as phosphorus and aluminum, optimize casting process parameters, accelerate ingot mold cooling, and pay special attention to moisture-proof storage environment. By taking these comprehensive measures, the degree of segregation and pulverization risk of ferrosilicon products can be effectively reduced, ensuring stable product quality.
To control segregation, it is necessary to control the thickness of 75% silicon iron ingots within 100mm and 45% silicon iron within 150mm, while appropriately reducing the casting temperature and accelerating the cooling rate. The pulverization problem is even more complex, mainly due to the formation of unstable phases by impurity elements in the alloy during solidification, followed by internal stress and crack formation during phase transformation. In a humid environment, it reacts with moisture to produce gas, ultimately leading to alloy fracture. Among them, impurities such as phosphorus and aluminum have the most significant impact, and alloys with 50% -60% silicon content have the greatest tendency to pulverize.
In production, it is necessary to start with raw material control, reduce the content of harmful elements such as phosphorus and aluminum, optimize casting process parameters, accelerate ingot mold cooling, and pay special attention to moisture-proof storage environment. By taking these comprehensive measures, the degree of segregation and pulverization risk of ferrosilicon products can be effectively reduced, ensuring stable product quality.