In our effort to develop metal cutting as a high strain rate test, we are interested in mapping the damage distribution over the primary shear zone (PSZ). The approach is to quantify the modulus degradation via nanoindentation and use this as a measure of damage. It is shown that the hardness of the material increases and the modulus degrades as it shears through the PSZ. Introduction There are...

Surface nanomechanical behavior under nanoindentation of ZrN and ZrCN film on NiTi substrate was studied. The surface hardness and modulus of the films increase initially with larger nanoindentation depths and then reach their maximum values. Afterwards, they diminish gradually and finally reaching plateau values which are the composite modulus and composite hardness derived from the ZrN/ZrCN f...

The structural and nanomechanical properties of GaSe thin films were investigated by means of X-ray diffraction (XRD) and nanoindentation techniques. The GaSe thin films were deposited on Si(111) substrates by pulsed laser deposition. XRD patterns reveal only the pure (000 l)-oriented reflections originating from the hexagonal GaSe phase and no trace of any impurity or additional phases. Nanoin...

We survey recent progress in the application of nanoindentation to characterize the local mechanical properties of polymer gels and biological tissues. We review the theories, analytical models based thereon, and data processing techniques commonly used to determine elastic properties of these classes of materials by instrumented nanoindentation. Examples from the testing of synthetic and biolo...

Nanoindentation is a technique commonly used for measuring thin film mechanical properties such as hardness and stiffness. In this study, we used the finite element method to investigate the effect of substrate and pileup on hardness and stiffness measurements of thin film systems. We define a substrate effect factor and construct a map that may be useful in the interpretation of indentation me...

color metallography is a useful method for characterizing microstructures of steels with multiple phases. in this paper, application of three different color etching techniques for a bainitic-martensitic steel is reported. comparisons between the results showed that 10% na2s2o5 aqueous solution was the best etchant for distinguishing martensite, bainite and ferrite phases. the obtained microgra...

A new technique, involving nanoindentation and in situ scanning probe microscopy at high temperature under an inert atmosphere, is used to study deformation of a Pt-based metallic glass. As temperature is increased into the supercooled liquid regime, impressions made by nanoindentation flatten due to surface tension-driven viscous flow. In situ measurements of shape recovery at various temperat...

We present results of parallel molecular dynamics simulations of nanoindentation and nanotribology experiments. The models we have developed describe both the sample and the indenter atomistically and model the effect of the cantilevers in an atomic force microscope through the use of springs. We show that the simulations are in good qualitative agreement with experiment and help to elucidate m...