When it comes to the test needed to be performed to measure or check the resistance of a material against failure due to a suddenly applied load or force, the test is known as an impact test.
What this test actually does is that it ends up measuring the energy absorbed in a material before it gets fractured. And, this absorbed energy is referred to as impact energy.
Now the question is how to measure this impact energy. Actually, there are mainly two methods: Izod Test and Charpy Test.
In this article, I have briefly described the Charpy Test.
Table of Contents
What is Charpy Test?
Charpy is the test that is used to calculate the impact toughness or relative toughness of materials (commonly metals). It is generally a relative test, not a definitive test.
Apart from metals, sometimes, the test is also performed on other materials like ceramics, polymers, etc. As far as the cost involved in the test is concerned, it is not too much.
I mean to say that the test is economical and can be completed within a short span of time.
[PS: You should also read our article on the difference between Hardness and Toughness so that you can understand Toughness in a deeper way.]
What does it involve?
Mainly, there are three things involved in the Charpy impact test. These three things are mentioned below:
- The specimen or test piece that is to be tested is fixed at both of its ends. There is a machined notch on one face of the specimen.
- On the other hand, there is a striker attached to the end of a pendulum.
- The striker hits or strikes the specimen in the face just opposite to the one at which the notch has been machined.
And, when it comes to the calculation of the impact energy with the use of this test, the process to calculate it is not too complicated.
When the striker strikes the specimen, its motion is slowed down and it is not able to rise as high as it can if there is no specimen resisting its motion.
So the impact energy of the specimen can be calculated on the basis of the difference between the height reached by the striker in the presence of the specimen and the height that it would reach if there were no specimen.
Charpy Impact Test Specimen
No need to mention that the test piece used in the Charpy test is known as the Charpy impact test specimen because it has already been indicated above in this article.
As far as the size of this specimen is concerned, it is generally 55x10x10 millimeters. And, there is a machined notch on one of its two larger faces.
There are mainly two types of notches that can be machined on the specimen. These two types are U-notch and V-notch.
Advantages of Charpy Test
There are many useful advantages or benefits offered by this test performed on materials. Below I have listed some of the most important and considerable advantages:
- There is a very big role played by this test in evaluating the quality of materials.
- The test delivers results very fast or within a short span of time.
- It is a simple test and you will find it very easy to perform it.
Final Words
So this was all about Charpy Test. I hope every point mentioned in this article is clear to you. If still, you have any doubts, you can make use of the comment section to ask your questions. I will try my best to reply as soon as possible.
And, below there are some hand-picked articles for you to read next:
Charpy Impact Test Machine – A Detailed Guide