Mechanical Properties

· The boundary between elastic and plastic deformation is hard to locate.
· The Offset Yield Stress,σ_y = σ_0.002 , is defined as that stress that produces a small permanent plastic deformation in the unloaded condition for which: (ΔL/L₀) = 0.002.
· Stresses less than this value are taken to produce only an elastic response. Larger stresses will produce permanent plastic deformation.

From: Callister, "Materials Science and Engineering," Wiley (1994)