As the Inoculant with various type with different feature. The main functions as below： 2.Promote the graphitization ,Reduce white cast tendency. 2.Refining the grains, reduce segregation, uniform structure. 3.Improve the mechanical strength,adjusting the hardness； Improve the mechanical properties . 4.Improve the primary structure, morphology and distribution of graphite. 5.Reduce the Internal stress and casting section sensitivity. The Inoculant push the development of high strength gray cast iron, and improve technique of vermicular iron casting and nodular iron casting .