Calibration of machine platform nonlinearity in Instrumented Indentation Test in the macro range

Metrological Comparison of Available Methods to Correct Edge-Effect Local Plasticity in Instrumented Indentation Test

“…Accordingly, ensuring high accuracy of the IIT characterization results is of utmost importance. Systematic error correction is achieved by ensuring a controlled temperature environment and the stabilization of the contact conditions [ 1 , 22 ], and by removing elastic contribution to the indenter displacement due to the machine frame compliance C f [ 23 , 24 , 25 ], and the sample contact stiffness S [ 25 , 26 , 27 ], and possible zero errors due to the first contact h 0 [ 28 ]: where is a parameter dependent on the indenter geometry. The frame compliance requires calibration [ 23 , 24 , 25 ] and ensures traceability.…”

“…Furthermore, geometrical errors in the indenter geometry are addressed by calibrating the area shape function, i.e., , either by direct [ 29 , 30 , 31 ] or indirect methods [ 23 , 24 , 32 ].…”

“…Historically, Vickers hardness was introduced, which is based on diagonal measurements, more robust to edge plasticity, to relieve the effects of edge effect in the case of spherical indenters [ 43 ]. Furthermore, at larger characterization scales typical of Vickers and Brinell hardness tests, the error introduced by the edge effect is negligible [ 24 , 44 , 45 ]. However, the need to resolve nanoscale hardness and the possibility of characterizing additional mechanical properties by IIT, made it necessary to find approaches to correct the systematic error introduced by the presence of non-negligible edge effects.…”

“…where ε is a parameter dependent on the indenter geometry. The frame compliance requires calibration [23][24][25] and ensures traceability. Furthermore, geometrical errors in the indenter geometry are addressed by calibrating the area shape function, i.e., A p (h c,max ), either by direct [29][30][31] or indirect methods [23,24,32].…”

“…The frame compliance requires calibration [23][24][25] and ensures traceability. Furthermore, geometrical errors in the indenter geometry are addressed by calibrating the area shape function, i.e., 𝐴 (ℎ , ), either by direct [29][30][31] or indirect methods [23,24,32]. Additional sources of bias are due to the physics of the indentation.…”