Also known as the microhardness test method, Vickers hardness testing procedure is commonly used to measure case depth, small parts and thin sections. It uses a diamond indenter to indent test materials at an angle of 136 degrees to a load of 1-100 kgf. EN ISO 6507, ASTM E-92 and ASTM E-384 specify that the indenter must be pressed into the material using a defined test load and then converted to a hardness value. It can be used in macro and microhardness tests due to its wide load range. This testing method is indispensable in the quality control of products, metallographic research and product certification. Given that the indentation test of Vickers is small, it is best for testing thin components and individual microstructures.
Preparing the Test Samples
With these tests, it is highly advisable to section components to ensure that you have pieces that can fit into the tester. In the preparation stage, the surface of the specimen has to be left smooth to allow for proper measurement and allow a perpendicular setting on the indenter, which then produces indentations in the form of a diamond. Usually, the materials are placed on a plastic medium after preparation to give room to proper testing. This method of hardness testing requires large indentations for maximum measurement resolution. It can be used to test ceramics, metal, composites and many other materials successfully, only when the test samples are prepared carefully. Note that the shape, size the degree of flatness and the condition of the surface are the top-most determining factors of the right hardness test method to use.