Learn

Stress-strain curve for mild steel

The stress-strain curve is the single most important diagram in mechanical engineering. It tells you exactly how mild steel behaves under tension from elastic deformation where the material springs back, through yield and strain hardening where it permanently changes shape, to ultimate tensile strength and finally fracture.

This interactive simulation lets you drag through every region of the curve and understand what's happening inside the material at each point: A (elastic), B (yield), C (UTS), and D (fracture). Built for engineering students, interview prep, and anyone who wants to understand why steel bends before it breaks. No formulas ;just drag and learn.


Try this simulation yourself

Drag the strain slider from left to right — watch the dot travel along the curve from elastic to fracture

  • Watch the A→B region — the straight steep line is Hooke's Law in action. Let go here and the steel springs back

  • Cross B (Yield 250 MPa) — this is the point of no return. Beyond here, deformation is permanent

  • See the curve flatten toward C (UTS 440 MPa) — the steel is getting stronger but running out of hardening capacity

  • Past C, the stress drops — necking has started. One weak spot thins out until fracture at D

  • The shaded area under the curve is toughness — total energy absorbed before failure. More area = tougher material