Cambridge Materials Testing
Charpy impact testing

Charpy impact testing, also known as the Charpy V-notch test, is a standardized high strain-rate test which determines the amount of energy absorbed by a material during fracture. This absorbed energy is a measure of a given material's notch toughness and acts as a tool to study temperature-dependent ductile-brittle transition. Charpy impact testing is performed on instrumented machines capable of measuring less than 1ft.lb. to 300ft. lbs. at temperatures ranging from -320F to over 2000F. Specimen types include notch configurations such as V-Notch, U-Notch, Key-Hole Notch, as well as Un-notched and ISO (DIN) V-Notch, with capabilities of testing sub size specimens down to 1/4 size. IZOD testing can be done up to 240ft.lbs.

A standard single notch on type-X3 specimens. Charpy impact Testing is commonly used on metals, but is also applied to composites, ceramics and polymers. With the Charpy test one most commonly evaluates the relative toughness of a material, as such; it is used as a quick and economical quality control device.

By applying the Charpy Test to identical specimens at different temperatures, and then plotting the impact energy as a function of temperature, the ductile-brittle transition becomes apparent. This is essential information to obtain when determining the minimum service temperature for a material.