Capacity of a given material to absorb vibrations by converting energy into heat, thanks to its elastic hysteresis characteristics. This coefficient provides a relative measurement of the cyclic amplitude reduction .

This is a very much sought-after property for applications requiring maximum vibration damping, such as machine tool frames and ways. In this regard, Gray iron is the ideal material, and is by far superior to cast or fabricated steels. Ductile iron can be a substitute to Gray iron whenever required for other specific reasons.