Question

Extensive plastic deformation occurs during

• A. Cold work
• B. Injection molding
• C. Casting
• D. Heat treatment

Hint:

Cold working increases strength through strain hardening and occurs below the metal’s recrystallization temperature.

Answer 1

The Correct Option is A

Step 1: Understanding Cold Work Cold working, also known as cold forming or work hardening, refers to the plastic deformation of metals below their recrystallization temperature. During cold working, dislocations multiply and move, resulting in extensive plastic deformation. Step 2: Other Processes - Injection molding: primarily involves melting and shaping polymers, not plastic deformation of metals. - Casting: involves pouring molten metal into a mold and solidifying it, not deformation. - Heat treatment: involves thermal cycles to modify properties; plastic deformation is not a primary mechanism. Thus, the process involving extensive plastic deformation is cold work.