BS2789 Grade 400-15 Spheroidal Graphite (SG) Iron, commonly known as ductile iron, is a highly versatile engineering material valued for its unique combination of strength, ductility, and impact resistance. As a ferritic spheroidal graphite cast iron, it delivers performance characteristics superior to standard gray cast irons, making it a preferred choice for a wide range of industrial components. Its exceptional properties stem from the presence of graphite in nodular or spheroidal form, which enhances its mechanical integrity and toughness. 

For engineering, design, and procurement professionals, understanding the specifications of Grade 400-15 is critical for selecting the right material for demanding applications. At Nifty Alloys LLC, we are a trusted supplier and stockist of high-quality SG Iron grades, including BS2789 Grade 400-15. We provide materials that meet rigorous international standards, ensuring reliability and performance for your projects in the UAE and beyond. This guide provides a detailed overview of its properties, applications, and equivalent grades to support your technical and procurement decisions. 

What is BS2789 Grade 400-15 SG Iron? 

BS2789 Grade 400-15 is a specific grade of spheroidal graphite cast iron defined by the British Standard BS 2789. This standard outlines the requirements for cast irons where the graphite is present in a spheroidal or nodular form rather than as flakes, which are characteristic of gray cast iron. The name "400-15" directly references its key mechanical properties: a minimum tensile strength of 400 MPa and a minimum elongation of 15%. 

The manufacturing process involves a critical step where magnesium is added to the molten iron. This treatment modifies the graphite's microstructure, causing it to form spherical nodules instead of sharp flakes. This structural change is fundamental to the material's enhanced properties. The rounded graphite nodules eliminate the internal stress points created by flakes, which significantly improves the material's ductility and impact strength without compromising its compressive strength. 

Due to this unique combination of properties, BS2789 Grade 400-15 is widely used for engineering castings and components that demand moderate strength, high machinability, and excellent toughness. Its reliability makes it suitable for parts subjected to dynamic loads and varying operational stresses.