Grey Cast Iron Castings

Grey cast iron (also called gray cast iron) is a group of cast iron including several kinds of grade according to different designation of diverse standards. Gray cast iron is a kind of iron-carbon alloy and it gets its name "grey" from the fact that their cutting sections looks grey. The metallographic structure of gray cast iron is mainly composed of flake graphite, metal matrix and grain boundary eutectic. During the grey iron, the Carbon is in the flake graphite. As one of the widely used casting metals, cast gray iron has many advangates in costs, castability and machinablity.

Performance Characteristics of Gray Iron Castings

• Liquid gray iron has good fluidity, and its volume shrinkage and linear shrinkage are small, and the notch sensitivity is small
• Low comprehensive mechanical properties, compressive strength is about 3~4 times higher than tensile strength
• Good shock absorption, the shock absorption of gray iron is about 10 times greater than that of cast steel
• Gray iron has low modulus of elasticity

Structural Characteristics of Gray Iron Castings

• Small wall thickness and complex shapes are available
• The residual stress of the casting is small
• Gray iron castings should not be designed with very thick structures, and asymmetrical sections are often used to make full use of their compressive strength