Ductile iron -- Has composition similar to gray iron. Special treatment modifies metallurgical structure which yields higher mechanical properties; some grades are heat treated to improve ductility.

• 球墨铸铁--其化学成分与灰口铁相似,其金相结构经过特殊处理后被改变,因此具有很好的机械特性;有些等级还经过热处理,进一步改善了可锻性。