Mechanical Engineering Impact Toughness Quiz

The primary difference between the Charpy and Izod techniques lies in the manner of specimen support.

The Charpy V-notch (CVN) technique is most commonly used in Europe.

The energy absorption in the impact-testing apparatus is computed from the difference between h and h̀.

The ductile-to-brittle transition is related to the temperature dependence of the measured impact energy absorption.

The temperature of the specimen has no influence on the test result and the fracture mode.

At higher temperatures, the CVN energy is relatively small, in correlation with a brittle mode of fracture.

The ductile to brittle transition temperature (DBTT) depends only on the material composition.

As the temperature is lowered, the impact energy increases and the nature of fracture mode changes from brittle to ductile fracture surface.

For brittle fracture, the surface appears dull and fibrous.

The appearance of fracture surface is not an indication for the nature of fracture and used in transition temperature determination.

The impact test measures the energy absorbed in breaking the specimen under shock loading or at high loading rates.

The impact energy value indicates the brittleness of the material under test.

The Charpy and Izod tests measure the impact energy or impact toughness of materials.

The specimen for both Charpy and Izod tests is in the shape of a cylinder.

The impact test conditions can be chosen to represent those most severe relative to the potential for ductile deformation.

One of the factors in impact test conditions is the triaxial stress state, which may be introduced by the presence of a notch.