Vickers Hardness Test
Definition - What does Vickers Hardness Test mean?
The Vickers hardness test is a test performed to measure the hardness of materials, specifically thin sections and small parts. It is comprised of a diamond indenter and a light load to produce an indentation on the subject under testing. The depth of indentation is converted into the hardness value of the object.
The smaller the indentation, the harder the object. Likewise, if the indentation is large, the material is lacking in hardness. This test is utilized by many industries to determine the right type of material to use for operations and machinery. A material with ideal hardness according to its purpose should be chosen.
The Vickers hardness test is also known as microhardness testing.
Corrosionpedia explains Vickers Hardness Test
The Vickers hardness test is done by pressing a particular indenter into the surface under testing. It only makes use of one test force, unlike with other types of hardness testing, such as the Rockwell hardness test. The resulting indentation is measured with the aid of eyepieces and high-powered magnifying instruments like microscopes. Some even make use of analyzing software to obtain fast and more accurate results.
The Vickers test uses two varying forces, such as the macro range from 1 to 100 kg and the micro range at 10 to 100 grams. The indenter that is used in both ranges is the same. Hence, the hardness values that are produced are constant over all ranges of metal hardness.
Since the indentation that is produced by the Vickers test is small, it can be very useful for applications like testing ultra-thin objects such as foils. It is also ideal for measuring small surfaces or parts, single microstructures or gauging the case depth hardening by dividing parts and producing an indentation series to determine a hardness change profile.
In order to obtain precise results, sample preparations are necessary. A sample that is adequately small to fit in the tester is required. Furthermore, the preparation should have a smooth surface to achieve a regular indentation shape and accurate measurement. This also ensures that the subject can be perpendicularly held onto the indenter.