Why should dephosphorization of molten iron in the steelmaking process?

Phosphorus, as a harmful element in steel, tends to segregate at the grain boundary, causing the steel to be cold and brittle, so most steels are required to reduce the phosphorus content.

In recent years, with the rapid development of clean steel production processes, the demand for low-phosphorus steel has been proposed. Such as the production of automotive surface hardened high-quality alloy steel, deep-drawn steel, tin plate, ultra-low carbon steel, bearing steel, high-grade pipeline steel, low-temperature steel and marine steel, etc. steel requirements w (P) less than 0.01 %, some even require less than 0.005%.

Therefore, how to stably and effectively control the content of phosphorus in the steel, especially in the case of high w(P) and w(Si) in molten iron. Solving the production of high-grade clean steel is the bottleneck in the steel mill smelting process.

The hot metal dephosphorization process originally originated in Japan. At present, the dephosphorization process of molten iron actually put into production in China mainly includes two types: dephosphorization outside the furnace and dephosphorization in the furnace.

Tags: dephosphorization, molten iron, steelmaking,