Grey Iron
Grey iron is a type of metal often used in castings. In the past, grey iron was known as cast iron; however, cast iron is now made out of iron-carbon alloys that have a higher level of ductility. Because of the low ductile properties of grey iron, high levels of tensile stress will result in its breaking or fracture. For this reason, grey iron is used most commonly in applications where tensile strength is not critical to the function of the component.
With the exception of wrought steel, grey iron is the most widely used metal for engineering purposes. Grey iron is an extremely inexpensive metallic material and is readily available in large quantities at almost any foundry. Grey iron is cast much like any other metal; it is poured into a mold and extracted after it cools. The method by which the grey iron is cast can have an effect on the mechanical properties of the metal, especially in respect to its cooling rate.
Grey iron castings are widely used in the automotive, appliance, agricultural, and machinery industries. Grey iron can be found in pump housings, electrical boxes, engine blocks, and decorative castings.