Two well-known methods to determine how resistant a material is are the Charpy and Izod impact testing. These tests determine what material can absorb overall energy. The degree to which the material absorbs energy is proportional to its brittleness.
This article will help you select the right one for your needs by explaining the differences between the two. Here are a few points that make each test unique and what they have in common.
What Is Impact Test?
An impact test checks how well a material can handle sudden shocks or loads that cause it to change shape. Many types of impact tests exist. They all involve putting pressure on a pre-made test sample with a weight.
Different impact tests and materials have specific testing procedures and specimen requirements. Materials testing standards like ASTM E23, ASTM A370, and ASTM D256 regulate these. Impact tests help determine a material’s ability to handle sudden loads.
However, they do not consider repeated load. We can compare the impact strengths of different materials if we use the same standard to assess them.
Types of Impact Testing
Here, we will explain the two main types of impact tests.
What Is The Izod Impact Test
The Izod method is commonly used to test how well materials can withstand impact. It involves raising and lowering an arm to a predetermined height, after which the arm strikes and breaks a sample. We then use the energy from this impact to calculate the notch sensitivity and toughness of the material.
What Is The Charpy Impact Test
The Charpy method measures the energy absorbed by a material. It does this by impacting the material at a high speed. We utilize the power to determine the material’s notch durability. This is a crucial technique for comprehending breakage issues.
Charpy Test Vs. Izod Impact Test: What Is the Differences
- Point of Strike
The point at which the mallet strikes the specimen differs for each specimen. The Charpy test and the Izod test have different striking directions. In the Charpy test, the hammer strikes the notch from the opposite direction. On the other hand, in the Izod test, the hammer strikes the upper apex of the specimen.
- Type Of Notch
U-notch and V-notch notches are both utilized in hardness testing. The Charpy method uses both V-notch and U-notch, while the Izod method only uses V-notch.
- Specimen Position
Each experiment positions the specimen differently. During the Charpy method, we positioned the test material horizontally instead of vertically in the Izod method.
- Direction of Notch
The specimen differs when it strikes it, and it has a distinct look. In the Charpy test, the notch face points away from the attacker. However, in the Izod test, the notch face faces the striker. The notch face is hanging from a pendulum in both tests.
- Specimen Dimensions
Each test uses different sample sizes, even if the material being tested is the same. It is the standard Charpy test sample, measuring 55 x 10 x 10 mm (2.165 inches x 0.394 inches x 0.394″). The standard Izod test sample measures 75 x 10 x 10 mm (2.95″ x 0.394″ x 0.394″).
- Hammer Type
Each test uses a different hammer as the striker. Izod uses the Farming hammer as the striker, while Charpy uses the Ball Pin hammer as the striker.
- Energy Measurement
The Charpy Impact Test measures the energy required to break a specimen. The Izod Impact Test measures the energy needed to create and spread a crack in the specimen.
Applications of Charpy and Izod Tester
Steel and Metal Industries:
Bridges, apparatus parts, and buildings are tested for impact durability using Charpy and Izod tests.
Research and Development:
Charpy and Izod tests aid in material research and development. Scientists use these tests to discover new materials that possess strong impact resistance. Additionally, they enhance the impact resistance of existing materials.
Polymers and Plastics:
Testing impact resistance is essential for evaluating the quality of polymers and plastic. It is used in many industries and products.
To Wrap with Charpy and Izod Impact Test
Charpy Impact testers and IZOD Impact testers are two distinct types of impact tests utilized to determine the impact resistance of materials. The IZOD tester tests plastics, while the Charpy tester tests metals. Engineers can use instruments to test materials and ensure their components meet specifications reliably.