Application: (1) in the steel industry used as deoxidizer and alloying agents. (2) in the iron industry used as a nucleating agent and spheroidizing agent. Cast iron is a kind of important modern industrial metal materials, it is much cheaper than steel, easy to melt refining, excellent casting performance and seismic capacity is far better than steel. Especially the nodular cast iron, its mechanical performance at or near the steel mechanical property. Add a certain amount of silicon in cast iron can prevent iron in formation and precipitation of carbides, and promote the graphite spheroidizing, therefore in the nodular iron production, ferrosilicon inoculants is a kind of important separation graphite (help) and spheroidizing agent. (3) used as a reductant in ferroalloy production. Not only chemical affinity between silicon and oxygen is very big, but also high silicon silicon carbon content is very low. So high silicon ferrosilicon (or siliceous alloy) is a low-carbon ferroalloy ferroalloy industry production more commonly used a reducing agent.