Contentful Paint

Indenters in hardness testing

An overview

Why indenters are important in hardness testing

Indenters are essential components in hardness testing. They apply a defined pressure force on the surface of the sample, creating impressions that are measured to determine the hardness of a material. Depending on the hardness testing method and application, different types of indenters are used, such as balls, diamond pyramids, or conical diamond points. These indenters vary in shape, size, and material composition based on the requirements of the materials being tested and the testing standard. Selecting the right indenter is crucial for the accuracy and reliability of hardness testing.

Different Types of Indenters in Hardness Testing

There are various types of indenters, each designed for specific hardness testing methods and material types. Below are some of the most common types:

Diamond Cone:

These indenters are mainly used in Rockwell hardness testing. The diamond cone has a tip with an opening angle of 120 degrees and is suitable for very hard materials. It offers high precision and long service life due to the extreme hardness of the diamond.

Carbide Balls:

These indenters are used in Brinell and Rockwell hardness testing. They are primarily used for softer materials such as metals and plastics. The balls come in various diameters, typically 1, 2.5, 5, and 10 mm. They offer good wear resistance and even pressure distribution. For Brinell hardness testing, the balls are often made of carbide and are also available in inch sizes.

Diamond Pyramids:

Used in Vickers hardness testing, these indenters have a pyramidal tip with a square base. The pyramid has an opening angle of 136 degrees. For measurements on thin layers and small samples, the Knoop diamond is used. This hardness testing method uses a rhombohedral pyramidal diamond indenter (long edge angle 172.5°; short edge angle 130°).

Non-magnetic Indenters:

For special applications where magnetic interference needs to be avoided, there are indenters made of non-magnetic materials. These are used in environments where the magnetic properties of the test samples could be affected, such as testing electronic components or in combination with magnetic test tables.


Indenters are critical for the accuracy and reproducibility of hardness testing. The selection of the right indenter depends on the material being tested and the specific hardness testing method. With a variety of options, from diamond cones and carbide balls to diamond pyramids and non-magnetic variants, every testing task can be performed efficiently and reliably. Using certified indenters according to ISO and ASTM standards ensures the quality and accuracy of the tests.

Accessoire filter

Choose machine
Choose category


made with passion by GO.WEST GO.WEST Communications Gmbh Logo