Why use Instrumented Indentation Testing?
The SMT-5000 platform offers the possibility for running micro indentation and nano indentation experiments by the modular interchangeable design. The traditional hardness tests (Vickers, Knoop, Rockwell, Brinell) are commonly used for bulk-materials, and require the accurate measurement of the resulting imprint. This could be very challenging and inaccurate, especially when a minor load is applied, which results in a small imprint. Also, it only provides information about the hardness of the material and does not give any other material properties (such as elastic modulus, storage/loss, creep or stiffness).
By contrast, the depth-sensing Micro- and Nano Indentation Testers can also be used for thin films, coatings and to determine material properties at local sample positions. Nano- and Micro Indentation measure the penetration depth as a function of the applied load. This provides the operator valuable information about the film/coating material properties at the top surface and, when increasing the load, also at the substrate interface.
For accurate measurement of coating and thin film properties, it is essential to apply the 10% rule; the maximum indentation depth should not exceed 10% of the coating/film thickness, as the applied load creates a stress in the material, which could affect the indentation depth.