Elongation at break measurement

What is elongation at break?

The elongation at break of a material is the relative change in length it reaches when it is stretched to the maximum, until its mechanical failure. It is often noted A% and expressed in %.

Fragile materials often have low elongations at break (eg cast iron). Conversely, there are ductile materials which have a very high elongation at break (polyester, polyethylene, etc.).

How it is measured?

The elongation at break is one of the parameters measurable during tensile tests. These tests consist of applying an increasing tensile force to a sample held between two jaws. The device used also measures the length of the sample. A sudden jump in length is measured when the sample breaks.