Ductile 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 creium) in the ladle. Graphite is in nodular or spheroidal form and is well dispersed throughout the material