A hardness tester is a device used to determine the hardness of a material. It works by forcing an indenter, under known load, into the surface of the material. The user would then measure the diameter of the indentation using a microscope. Hardness testers feature a rounded or pointed indenter, usually a diamond, carbide or hard steel, which is used to make indentation on the sample’s surface.
A hardness tester is essential in determining if a material is suitable for the task at hand. It allows you to assess a material’s characteristics, such as flexibility, wear-resistance and strength.
There are three primary types of hardness testers, characterized by the kinds of hardness tests they perform: Brinell hardness tester, Rockwell hardness tester and Vickers hardness tester.
Brinell Hardness Tester
A Brinell hardness tester is used to determine the hardness of a material using the Brinell hardness test method. It is the most suitable device to measure the hardness of materials whose surface is too coarse to be measured using another method. This hardness tester utilizes a high test load and a 10mm diameter indenter, ensuring the resulting indentation evens out the inconsistencies on the surface.
Rockwell Hardness Tester
This hardness tester is commonly used as it is easier to perform and gives more accurate results than the other methods. It is perfect for all metals, but you should not use it in the following conditions;
- The test metal surface would introduce too many variations
- If the indentations would be too large for application
- The shape of the sample material prohibits the use
Vickers Hardness Tester
Vickers hardness tester, also known as microhardness tester, is used on all types of materials. However, it is perfect for measuring the hardness of thin materials as the indentation is minimal. You can use this microhardness tester on any material, including ceramics and composites.