The process of toughening a metal through plastic deformation?

The process of toughening a metal through plastic deformation?

• A. Quenching
• B. Tempering
• C. Annealing
• D. Work hardening

Answer: (D)

The process relies on plastic deformation to increase a metal’s strength and hardness. When metal is deformed at room temperature, dislocations multiply and interact, forming a dense network that blocks further movement of dislocations. This makes it harder for the material to deform again, raising yield strength and hardness. That’s why this approach is described as work hardening. Other treatments involve heat: quenching rapidly cools to form hard phases; tempering reduces brittleness after quenching; annealing heats and slowly cools to relieve internal stresses and soften. So the method that uses plastic deformation to increase strength is work hardening.

The process relies on plastic deformation to increase a metal’s strength and hardness. When metal is deformed at room temperature, dislocations multiply and interact, forming a dense network that blocks further movement of dislocations. This makes it harder for the material to deform again, raising yield strength and hardness. That’s why this approach is described as work hardening. Other treatments involve heat: quenching rapidly cools to form hard phases; tempering reduces brittleness after quenching; annealing heats and slowly cools to relieve internal stresses and soften. So the method that uses plastic deformation to increase strength is work hardening.