Impact strength

Impact strength describes a material's ability to absorb impact and shock energy without breaking. Numerous factors influence the impact resistance of a component, including:

Wall thickness
Shape and size of the component
Temperature
Impact velocity

Impact strength is measured using an impact hammer. Impact strength is calculated as the ratio of impact work to specimen cross-section (unit kJ/m²).

There are three different methods for measuring impact resistance:

Izod impact strength: Here, the test specimen is clamped upright.
Charpy impact strength: In this method, the test specimen is held at both ends and struck in the middle. Materials with very high impact strength do not break.
Notched impact strength: This method uses a notched specimen. Due to the stress concentration, the measured values are significantly lower. Notched impact strength provides information about the notch sensitivity of a material.