Fundamental material property — term for permanent retention of deformation Which property name describes a material's ability to retain deformation permanently after removal of the applied load (i.e., non-recoverable strain)?

Introduction / Context:
In mechanics of materials, engineers distinguish between elastic behavior (recoverable strain) and plastic behavior (permanent strain). Correct terminology matters for forming processes, failure analyses, and setting allowable limits in design standards.

Given Data / Assumptions:

• The load is high enough to exceed the elastic limit of the material.
• After unloading, the deformation that remains is permanent (plastic).
• Common related terms include ductility, malleability, brittleness, and resilience.

Concept / Approach:
Plasticity = ability to undergo non-recoverable (permanent) deformation without fracture.It is a general term encompassing both tensile and compressive plastic flow. Ductility is specifically the ability to undergo significant plastic deformation in tension before fracture (e.g., measured by elongation or reduction of area). Malleability refers commonly to plastic deformation in compression (e.g., rolling, hammering). Brittleness is the tendency to fracture with minimal plastic deformation. Resilience is energy stored elastically and recovered upon unloading.

Step-by-Step Solution:

Verification / Alternative check:
Stress–strain curves show that beyond yield, unloading follows a line parallel to the elastic modulus, leaving a permanent offset strain — this residual is the hallmark of plasticity.

Why Other Options Are Wrong:

• Brittleness: implies little to no plastic deformation.
• Ductility/malleability: subsets of plasticity in tension or compression, not the general definition asked.
• Resilience: pertains to elastic energy storage, not permanent deformation.

Common Pitfalls:
Using “ductility” whenever permanent deformation occurs, even in compression or shear; equating resilience with strength.

Final Answer: