A Charpy impact testing is conducted to determine the strength of materials, such as metals, ceramics, polymers, and composites. It measures the energy absorbed by the material when it is broken by creating a notch and applying impact load. The material to be tested must be the standard unit measurement, commonly 55 mm x 10 mm x 10 mm. Then a machine-made notch is created in the material. The material is, then, hung from a pendulum. Finally, the material is hit with a hammer or similar object to create an impact, opposite to the notch. The energy absorbed is displayed on the screen. This method is an economical way of measuring the strength of a material under impact load.
A few specific measures must be taken to ensure an accurate reading:
- The notch on the specimen used for Charpy Impact Testing must be machine-made as a human-made notch, which might alter the results with force.
- The V-notch created in the specimen should not be too high or too deep into the compress.
- The specimen selected for Charpy Impact Testing must be placed at an appropriate height.
- A low-placed specimen will calculate a lower force as applied to the material.
- A high-placed specimen will generate an inaccurate reading of the strength of the material.
- The temperature of the specimen is a significant factor, as well. A higher temperature might cause inaccurate readings.
- The rate of strain provided through impact or pressurization also plays an essential role in the test.
Charpy Impact Testing is a cost-effective method used by manufacturers and engineers to produce materials of accurate strength. These materials are further used in creating various products, including pre-engineered structures. Thus, the test's accuracy is essential as the by-products are often used in buildings and machinery. If the Charpy test results are amiss, it could have drastic consequences in the production and the finished products. Therefore, the test must be precise.
