Ductile Cast Iron
What is ductile cast iron?
Ductile cast iron, also known as nodular cast iron, is a type of cast iron in which graphite appears as spherical inclusions. This structure is achieved by adding about 0.04% magnesium to molten iron, which changes the shape of the graphite from flake to spherical. The spherical graphite inclusions weaken the mechanical properties less than flake graphite, which gives ductile cast iron properties closer to those of steel.
Properties of ductile cast iron
Ductile cast iron offers an excellent combination of strength, toughness, and castability. Its tensile strength can be up to 900 MPa, making it suitable for demanding applications where high durability is required. Additionally, it is highly resistant to pitting, making it a popular material for manufacturing, for example, gears.
Use of ductile cast iron in the mechanical engineering industry
In the mechanical engineering industry, ductile cast iron is valued for its excellent machinability and castability. While its castability is slightly lower than that of gray cast iron, it still surpasses steel, and its machinability is nearly as good as that of gray cast iron. These properties make it ideal for manufacturing complex and precise components.
Applications of ductile cast iron
Ductile cast iron is widely used in various applications such as engine components, rolls and press molds, furnace parts, and grate bars. Its high tensile strength and excellent wear resistance make it an outstanding choice for these uses.
Summary
Ductile cast iron combines the best qualities of cast iron and steel, offering excellent strength, toughness, and castability. Its spherical graphite inclusions improve mechanical properties, making it a popular material for demanding mechanical engineering applications.
