The ability of metal to return to its original size and shape after being loaded and unloaded is called:

• A. Plastic deformation
• B. Elastic deformation
• C. Tensile strength
• D. Stress-strain deformation

Answer: (B)

The ability to return to the original size and shape after loading and unloading is elastic deformation. When a metal is stressed within its elastic limit, the atomic bonds stretch but do not permanently rearrange, so once the load is removed the material snaps back to its original form. This reversible behavior is described by the linear elastic range (often modeled by Hooke’s law), where strain is proportional to stress. If the applied load exceeds the elastic limit, the material yields and undergoes plastic deformation, resulting in permanent change. Tensile strength measures the maximum stress a material can withstand before failure, not its ability to rebound after unloading. The term stress-strain deformation isn’t a standard way to describe recoverability, as it describes the relationship between stress and resulting strain rather than the reversibility of deformation.