Development of macro-depth-sensing-indentation instrumentation

Using the Instron 5848 Microtester equipped with an additional displacement sensor and specially designed jigs as the main loading setup, DSI (depth-sensing indentation) tests were performed on typical metallic materials at a macro range. From the indentation data, the hardness and modulus of the materials were directly extrapolated without a frame compliance calibration, with an analysis procedure proposed by Oliver and Pharr. In this analysis, the contact area was calculated for indentation depths ≥ 6 μm from the area function of an ideal indenter tip and for depths < 6 μm from the area function suggested by Liu and Zhang. A comparison between our results and those from the MTS Nano Indenter^® XP shows that the repeatability is ideal, and the scatter of both hardness and modulus values is within 10%. So, it is feasible to develop the DSI capacity for traditional material testing machines.