Charpy testing is a method for determining the relative impact strength of metals. It is also known as the Charpy V notch test. This testing method was developed in the 1940s by S.B. Russell and G. Charpy. This is a standard method for testing the impact strength of a component containing a stress concentration.
The characterization of the toughness of a material can be achieved in several ways, but Charpy and Izod tests are the most common methods. The Charpy test determines the amount of energy absorbed by the material during fracture.
The energy absorbed by the material gives a measure of its toughness and facilitates the study of the temperature dependent ductile-brittle transition.
Charpy Test Method
The setup needed for Charpy testing consists of a rectangular beam of metal to be tested, notched in the center and placed between two anvils.
A swinging pendulum then breaks the metal beam and the total energy absorbed by the metal is determined by comparing the height to which the pendulum rises after impact and the height from which it was dropped.
From this energy calculation, a metal's notch toughness can be found, which in turn enables the tester to study the ductile-brittle transition.
The transition from brittle to ductile behavior occurs over a certain temperature range, which is different for different metals.
Advantages of Charpy Test
Some of the advantages of Charpy test include:
- Cost effective test method for composites
- Relatively easy to perform
- Helps to assess quality of a product
- Useful for evaluating new products
- Provides fast measurement results.
Some of the primary application areas of Charpy test are listed below:
- Materials testing
- Construction of pressure vessels
- Determining the impact strength of bridges
Sources and Further Reading
- Notched Bar Impact Testing of Materials – California State University
- Impact Strength of Steel and Manufacturing Statistics – Rochester University
- Impact Testing of Advanced Composites – Iowa State University