The property of a material to return to its original shape and size after the applied load is removed.
In the elastic region, stress and strain are linearly related by Hooke's Law: σ = E·ε. Deformation is fully reversible: no energy is dissipated. The elastic limit is the maximum stress that can be applied without permanent set. For most engineering materials, the elastic limit is close to the yield strength. Rubber is elastic but non-linear (hyperelastic) over large strains.
Elastic design keeps all service stresses within the elastic range. Springs, snap-fits, and compliant mechanisms rely on elastic deformation to store and release energy. For FDM snap-fits, the design strain at snap-through must stay below the elastic limit to avoid permanent deformation during repeated use.
The elastic region is narrower in FDM parts than in bulk material due to microstructure and layer interfaces. Viscoelastic polymers (most thermoplastics) show time-dependent elastic behaviour: creep begins even below the yield point under sustained load. A snap-fit that passes first-assembly testing may permanently deform if held closed for extended periods.
Related terms: Young's Modulus, Plasticity, Stress-Strain Curve, Stiffness
| Field | mechanics, engineering |
|---|---|
| Also called | Elastic Behaviour, Elastic Region |
Engineer, author of The Big Book of 3D Printing and additive manufacturing expert