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Helically Perforated Thin Films -- Dependence of MechanicalProperties on Microstructure

Published online by Cambridge University Press:  26 February 2011

Sumudu P. Fernando ,
Anastasia L. Elias  and
Michael J. Brett
Sumudu P. Fernando
Affiliation:
sumudu@ualberta.ca, University of Alberta, Electrical and Computer Engineering, University of Alberta, ECERF, 9107 - 116 St., Edmonton AB, Edmonton, T6J1P3, Canada
Anastasia L. Elias
Affiliation:
sumudu@ualberta.ca, University of Alberta, Electrical and Computer Engineering, University of Alberta, ECERF, 9107 - 116 St., Edmonton AB, Edmonton, T6J1P3, Canada
Michael J. Brett
Affiliation:
sumudu@ualberta.ca, University of Alberta, Electrical and Computer Engineering, University of Alberta, ECERF, 9107 - 116 St., Edmonton AB, Edmonton, T6J1P3, Canada
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Abstract

The effects of several microstructural parameters on the mechanicalbehaviour of a helically perforated thin film structure, or inversemicrospring, were investigated using a finite element model[1]. Theparameters investigated were the helical pitch angle, the cross-sectionradius, and the coil spacing. The elastic modulus was found to depend moststrongly on the helical pitch angle (changing by a factor of 1.3 as thepitch angle went from 35° to 70°). Variations in the coil radius and thefilm thickness had a minor effect on the modulus. It was also found thatusing a finite size model (as opposed to an infinite model using periodicboundary conditions) produced better conditioned results. A preliminaryconfirmation of the model's validity was performed by comparison tonanoindentation results of a nickel helically perforated thin film.

Keywords

simulationelastic propertiesnanoscale

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References

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