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A Model of Superlattice Yield Stress and Hardness Enhancements

Published online by Cambridge University Press:  15 February 2011

XI Chu
Affiliation:
Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208
Scott A. Barnett
Affiliation:
Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208
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Abstract

A model is presented that explains the yield stress and hardness enhancements that have been observed in superlattice thin films. The predicted strength/hardness enhancement increased with increasing superlattice period, Λ, before reaching a saturation value that depended on interface widths. The results indicate that superlattice strength/hardness depends strongly on interface widths and the difference in shear moduli of the two components for Λ values below the maximum, and on the average shear modulus for larger Λ.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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