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Nanoindentation of Thin Films with Nonhomogeneous Interphase In this study, we investigated the effect of modeling a interphase between a film and a substrate as a nonhomogeneous layer and quantified the effect of several extrinsic and intrinsic parameters such as film thickness, type of indenter, elastic moduli of the layers, and contact load. For this purpose we modeled a homogeneous or nonhomogeneous layer (film) on a homogeneous half-plane (substrate) separated by a nonhomogeneous or homogeneous interphase.
The objective of this study was to
study the effect of various
Also, using statistical analysis we quantitatively found the effect of various factors on contact depth ratio, maximum normal stress ratio and maximum shear stress ratio. Interface to layer thickness ratio has major impact on contact depth, maximum interface normal stress and maximum interface shear stress ratios. Indenter to layer thickness ratio has the least impact on maximum interfacial stress ratios whereas the impact of type of elastic moduli variation along the width of interface is minimum on contact depth ratio.
P. Chalasani, A. Kaw, J. Daly, C. Nguyen, Effect of geometrical and material parameters in nanoindentation of layered materials with an interphase, International Journal of Solids and Structures, Vol. 44, No 16, pp. 5380-5395, (2007). Sponsor: Department Principal Investigator: Autar Kaw |
parameters involved in layer-substrate indentation experiments. We
found that for a stiffer layer on a compliant substrate, the results
for contact depth are almost same for homogeneous or nonhomogeneous
interphase, where as there is significant difference (up to 15%) in
maximum interfacial normal stress and maximum interface shear stress
values for homogeneous and nonhomogeneous interphase. We conclude
that nonhomogeneous interface influence maximum interface normal
stress and maximum interface shear stress significantly and this
factor should be given due consideration in design.