Nanoindentation system for material properties identification / Teo Adrian Wei Hong, Yeap Gik Hong and Loo Wei Jie

This paper proposed to design a nanoindentation
system with the intention to identify material properties without
spalling. The system is designed to perform simulation based on
the load-depth curve data collected from NanoTestTM. The
hardness results are compared with Brinell hardness test and
NanoTestTM for the same materials; i.e. brass, mild steel,
aluminium and copper. Oliver-Pharr and Joslin-Oliver methods
are selected to measure the material properties. Both selected
methods require indentation load, impression area and depth to
fulfil the material properties calculation while these signals are
collected through a displacement sensor and an actuator. The
results collected indicate that the spall of material rate, which can
be reduced by decreasing the indentation load while maintaining
the indentation depth at a longer dwell time. The theoretical
simulation result of Joslin-Oliver method which neglects
substrate effect acquired an average error rate of 7.823%
whereas Oliver-Pharr method acquired an average error rate of
6.355%, both with comparison against NanoTestTM machine. The
experiments have been performed using same materials; i.e.
brass, aluminium, copper and mild steel.