Question

Which of the following deformations is/are irreversible?

• A. Elastic deformation
• B. Plastic deformation
• C. Fracture
• D. All of the above

Answer 1

Answer: (B), (C)

The correct options are
B Fracture
C Plastic deformation

$Answer:-$ B,C

In the image you can see that before yield point stress strain curve is linear and this is the region of elastic deformation(reversible).

But if you exceed this yield point permanent deformation occurs and at later stages fracture also may occur and theses two are irreversible.