Malleable Iron
A cast iron made by prolonged annealing of white iron in which decarburization,graphitization or both take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface; hence whiteheart malleable. Otherwise, the fracture surface will be dark;hence blackheart malleable. Only the blackheart malleable is produced in the United States. Ferritic malleable has a predominantly ferritic marix;pearlitic malleable may contain peaaaarlite,spheroidite or tempered marensite, depending on heat treatment an desired hardness.
