Here at Bell City Foundry we produce multiple grades of gray and ductile iron. The difference in these types of iron are as follows:
Gray Iron got its name from its dull gray surface appearance when it fractures. Gray Iron is the most widely used cast material based on weight. Benefits of Gray Iron are the following:
Gray Iron is used for housings where tensile strength is non-critical, such as internal combustion engine, cylinder blocks, pump housings, valve bodies, electrical boxes, and decorative castings. Gray Iron’s high thermal conductivity allows for such uses as cast iron cookware and disc brake rotors.
Ductile Iron is when the graphite is like a pillow and acts as “crack-arresters” to give ductility and toughness superior to all other cast irons. Benefits of Ductile Iron are the following:
Ductile iron is much more flexible and elastic, due to its nodular graphite inclusions. Ductile iron is specifically useful in automotive components, agricultural tractors, and oil well pumps, where strength needs surpass that of aluminum but does not necessarily require steel.