Malleable cast iron
A
Contains 1.7 to 3.5% carbon in Free State and is obtained by the slow cooling of molten cast iron
B
Is also known as chilled cast iron and is obtained by cooling rapidly. It is almost unmachinable
C
Is produced by annealing process. It is soft, tough and easily machined metal
D
Is produced by small additions of magnesium (or cerium) in the ladle. Graphite is in the nodular or spheroidal form and is well dispersed throughout the material
Correct Answer: Is produced by annealing process. It is soft, tough and easily machined metal
Malleable iron is cast as white iron, the structure being a metastable carbide in a pearlitic matrix.Through an annealing heat treatment, the brittle structure as first cast is transformed into the malleable form.
