(Notch) impact strength

The impact test according to DIN EN ISO 179-1 determines the toughness of a material under impact loading. The test specimen is positioned on two abutments and subjected to impact in the middle by the pendulum hammer of a pendulum impact tester, from which the necessary fracture work is determined.

A special type of test is the determination of notched impact strength, in which specimens are notched prior to testing to simulate notches in the geometry of a component, which represent weak points for mechanical loading and are almost impossible to avoid in reality. Due to the stress concentration at the notch, the determined notched impact strength values are significantly lower than those of the impact strength. The difference between impact strength and notched impact strength provides information about the sensitivity of the material to geometric influences. Depending on the specimen material and the task, different types of notches are used.