Chemical Engineering Basics - Engineering

Q1:

Cold working of a material results in increase in hardness, which is termed as the __________ hardening.

A cold

B work

C age

D induction

ANS:B - work

The correct term is "work hardening." Explanation:

  • Work hardening, also known as strain hardening, occurs when a material is plastically deformed at room temperature or below its recrystallization temperature.
  • During cold working, the material undergoes plastic deformation, causing dislocations to move and accumulate, which impedes further deformation.
  • This accumulation of dislocations increases the material's resistance to deformation and strengthens it, resulting in an increase in hardness.
  • Work hardening is a common phenomenon observed in metals subjected to processes like rolling, forging, drawing, or extrusion at room temperature.