Page 30 - report P Lemoine feb 2013c

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Microscope objective

Indenter
head

.
Sample stage
Figure B2: Photograph of the Nanoindenter system.

0.8

0.6
Load (mN) 0.4

0.2

0
0 20 40 60 80
Displacement (nm)

Figure B3: Typical load-displacement curve

Analysing the unloading segment of this curve (as the indenter is pulled away from
the sample) we note a ~30nm elastic recovery of the sample and a~43nm plastic

depth. If one can also gain access to the contact area of the indenter on the surface

(by microscopy of the indent or calibration of the tip area function with a fused silica
sample, see below), then the elastic recovery and the plastic depth can be used to

calculate the Young Modulus (E) and the Hardness (H). The details of these

calculations are explained in W.C. Oliver and G.M. Pharr, J. Mat. Res., 7(6) (1992)
pp1564-1583. Considering the depth h and load L, the various steps of the method

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