Gray iron is an alternative for economical, castable products with ease of machining. Relative to cast steel, gray iron provides improved surface hardenability, vibration damping, castability, corrosion and wear resistance and at a lower cost to manufacture.
Common applications of gray iron are similar to ductile iron, and specifically where complex design is required or other engineering design considerations by the customer that do not require high tensile strength or ductility. Examples of products using gray iron: engines, motor casings and machine tools. Gray iron provides an excellent sliding surface, resists galling and seizing. Heat treatment may be used to increase hardness.
Typical gray iron classes, designated by ASTM A48 are: