Definition:Permanent Set

Definition

Let a body $\BB$ be deformed under stress.

Consider the following stress-strain diagram.

Let $\BB$ be subjected to stress which takes the stress-strain diagram out of the elastic region and into the plastic region.

When the stress is removed, and $\BB$ no longer returns to its original shape, its deformed shape is known as a permanent set.

Consider the following stress-strain diagram:

$OF$ represents the permanent set of $\BB$ after it has been subjected to the stress which has been removed at point $C$.

Also known as

A permanent set is also known as just a set, but the latter is ubiquitous in mathematics to mean something completely different.

Also see

• Definition:Plastic Region
• Definition:Yield Stress
• Definition:Elastic Region

• Results about permanent set can be found here.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): Hooke's law
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): Hooke's law