Question

Hardness and strength in steel originate from the presence of perlite (which contains iron and iron carbide) grains, while ductility originates from ferrite grains.

a) True
b) False

Answer 1

The presence of pearlite gives strength and hardness to steel due to the layers of ferrite and iron carbide, while ductility comes from the ferrite grains, making the statement true.

Step-by-step explanation:

The statement about the origin of hardness and strength in steel from the presence of pearlite is true. Pearlite is a microstructure consisting of alternating layers of ferrite and iron carbide (cementite) which provides steel with its strength and hardness. The softer and more ductile microstructure known as ferrite, which is essentially pure iron with a body-centered cubic crystal structure, contributes to the ductility of steel.

Thus, in steel, pearlite contributes to hardness and strength due to the interlamellar spacing of ferrite and cementite, while ferrite grants the material its ductility.