Question

In an iron - carbon alloy, the content of carbon is stated to be 4.3 percent. Such a cast iron is known as -

• A. Hypo eutectic cast iron
• B. Hyper eutectic cast iron
• C. Eutectic cast iron
• D. Such a nomenclature does not exist

Answer 1

Answer:

C. Eutectic cast iron

An iron-carbon alloy with 4.3% carbon is known as eutectic cast iron. Cast iron with carbon content above 4.3% is hyper- eutectic, while that below 4.3% is hypo-eutectic. Plain carbon steels with less than 0.8% carbon are hypo-eutectoid, while those with more than 0.8% carbon are hyper-eutectoid. A 0.84% carbon steel is known as pearlite steel and is stronger than ferrite or cementite.