Gray cast iron is a state in the state many of the gang that based on their microstructure to one classification. The surface of the gray cast iron in the fracture is gray cast iron, is characteristic of ferrite and graphite free. During the freezing process, so slow speed radiator in molding sand, graphite of people to dissolve in liquid iron have enough time to release the small plates, free shapes (usually sheets) .

The chemical composition of gray iron includes mainly: iron (more than 95% by weight), and the main alloying elements are carbon and silicon 2.5-4% 1-3%.

Characteristics of gray cast iron

Gray cast iron with a low cost and relatively easy smelting, has a low melting temperature (1350 ° C) and is not demanding on impurities. Gang Gray taking good casting and high mute capabilities, so organizations are also porous material advantages for containing lubrication oil. However, cast iron brittle, poorly resistant to bending, can not be forged. When quenching the mold, white iron is very difficult to turn processed by mechanical machinery.

Classification of gray cast iron according to ASTM A48

Characterization of gray cast iron grade according to SAE J431

Comparing the damping of some metals

Application of gray cast iron

Due to the characteristics of the gray cast iron so people use them a lot in the engineering industry, the ice machine casting large, high complexity, the details do not need to take greater flexural, but needs a good compression strength . Having the equipment and materials used gray cast iron to> 70% of the total weight. The ice machine tools (turning, milling, planing, ...), the body of an internal combustion engine ... and are manufactured from gray cast iron.