DME University

Impact Strength


Impact testing is used to measure toughness or the ability to withstand a sudden impact or shock. Impact can also be defined as the amount of energy required to fracture a given column of material. Since hardness and temperature have a direct affect on a material’s impact resistance, it is important to test samples in controlled environments that approximate the actual operating conditions. The most common tests for impact are the Charpy and Izod tests.

This photograph shows the equipment used to perform Charpy and Izod impact tests. In both tests a 10mm square specimen is used with a V notch of specified shape and depth. The Charpy specimen is supported at both ends horizontally, while the lzod specimen is supported at one end vertically. A pendulum is released breaking the specimen. The amount of energy required to break the specimen is recorded by a scale at the top of the machine.



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