Izod vs Charpy Impact Test Key Differences Engineers Must Know.pdf

HEICO Dynamics’ Izod Charpy impact tester uses two standard methods for determining the impact resistance of a material. Both provide helpful information about how rigid a material is, but they are set up differently, object-oriented, and used in distinct ways.

1. Izod vs Charpy Impact Test: Key Differences
Engineers Must Know
In materials engineering, it is essential to know how a material reacts to a sudden hit.
HEICO Dynamics’ Izod Charpy impact tester uses two standard methods for determining the impact
resistance of a material.
Both provide helpful information about how rigid a material is, but they are set up differently, object-
oriented, and used in distinct ways.
Engineers must be aware of these differences to select the most suitable method for each job.
Why Impact Testing Is Done
The primary goal of both the Izod and Charpy impact tests is to determine the amount of energy a
substance can absorb before it fractures.
In turn, this helps engineers determine if a material is suitable for use with quick or changing loads.
Impact testing is essential in fields such as manufacturing, construction, aerospace, and automotive
because failure of materials can pose significant safety risks.
The Izod Impact Test
One of the best ways to test for impact is the Izod impact tester.
As shown, a specimen with a notch is held upright like a cantilever, and a pendulum hits it at the very
top.

2. The test finds out how much energy the sample can have before it breaks.
Based on the fact that the sample is positioned vertically, Izod testing is most effective for materials
that are loaded from above, such as beams or shafts.
It is usually used on plastics, resins, and some metals that need to be resistant to notch sensitivity.
The Charpy Impact Test
HEICO Dynamics’ charpy impact tester works similarly, but the specimen is put differently.
The specimen with the notch is held up on both ends like a simple beam, and the pendulum hits it in
the middle, behind the notch.
The amount of energy received shows how rigid the material is.
Charpy testing is excellent for checking structural materials like steels and metals because it is set up
horizontally.
For example, in bridges, pipelines, and pressure vessels, where big pieces of material are hit quickly
and hard, this method is widely used.
What's Different Between the Charpy and Izod Tests
Both tests measure impact energy, but they are set up and used in very different ways.
Specimen Orientation: Izod uses an upright specimen, while Charpy uses one that is flat on the
table.
Support: Izod clamps one end of the object, while Charpy holds both ends up.
Striking Point: In Izod, the pendulum hits the top of the specimen, but in Charpy, it hits in the
middle, behind the notch.
Uses: Izod works better with plastics and resins, while Charpy is more often used with metals
and building materials.
Because of these differences, izod vs charpy tester results can't be used directly with either method.
Instead, engineers have to choose the process based on the material and how it will be used.
Conclusion
Both the Izod and Charpy impact testers from HEICO Dynamics are essential for determining a
material's rigidity, but they are designed for different applications.
Charpy is often used for structural materials that are under heavy loads, while Izod is best for testing
cantilever-type uses and notch sensitivity.
Engineers can make decisions that ensure materials work safely and reliably under impact conditions
by knowing these key differences.
Also read: Types of Material Strength: Tensile, Compressive, Shear & More Explained