Cast iron gears are subcategory of gears. Cast Iron Gears is also known as grey iron and provides good stability, smooth surface finish. The color of surface is used to identify an alloy. White cast iron gears is one which allows the cracks to pass in straight direction and grey iron is one which initiates countless cracks as the material breaks and passing crack deflect graphitic flakes.

Cast iron is brittle in nature. They have good fluidity, wear resistance, low melting point, and excellent machinery, cast iron gears become a fabulous engineering material and used in pipes, automotive industry parts, machines like cylinder blocks, gearbox, and cylinder heads.

A method called welding of fabrication is used I cast iron by joining metals. This method is used for structural purpose. By heating a blanket at a temperature that is compatible to the blanket and forming a tooth part, a cast iron gears can be made.

Many ductile iron is cast iron as it large amount of carbon in the matrix. Gears that are made up of cast iron gears rely on low manufacture cost and easy to use with high damping. They are used in commercial gears. Cast iron gears has variety of advantages like long service life; ability to obtain high hardness, production cost is low.