Indentation Process Overview; Continuous Load-Displacement Data - Agilent Technologies Nano Indenter G200 User Manual

Indentation Process Overview

Continuous Load-Displacement Data

Agilent Nano Indenter G200 User's Guide
As the indenter is driven into the material, both elastic and plastic
deformation cause the formation of a hardness impression conforming
to the shape of the indenter to some contact depth, h
Figure 7-1. As the indenter is withdrawn, only the elastic portion of the
displacement is recovered; this recovery enables one to determine the
elastic properties of a material.
Figure 7-1 Schematic of indentation load (left) and residual impression
(right)
A set of continuous load-displacement data is shown in
page 7-4. Some important quantities are:
• Peak load (P )
max
• Displacement (h
max
• Residual depth after unloading (h
• Slope (S) of the initial portion of the unloading curve, where
)
)
f
S= dP/dh
Theory 7
, as shown in
c
Figure 7-2 on
(4)
7-3