Why Slag Inclusion Defects Occur in Ductile Iron Castings—and How Foundries Solve Them
In ductile iron foundries, slag inclusion defects are more than a surface imperfection—they represent a significant quality and cost challenge. These defects can weaken mechanical properties, create machining issues, increase rejection rates, and ultimately affect long-term customer relationships. For foundry managers, metallurgists, and industrial buyers, understanding why slag inclusions occur—and how reliable foundries prevent them —is critical for maintaining consistent casting quality and meeting demanding application standards. This article explains the root causes of slag inclusion defects, their impact on ductile iron performance, and the practical solutions leading foundries use to control and eliminate them. What Are Slag Inclusion Defects in Ductile Iron? Slag inclusions are non-metallic impurities trapped within or on the surface of ductile iron castings. These inclusions are typically composed of oxides, silicates, sulfides, and residues generated during melting and treat...
