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Grain- and phase-boundary stress effects in nanocrystalline materials

✍ Scribed by R. Birringer; P. Zimmer

Publisher
Elsevier Science
Year
2009
Tongue
English
Weight
555 KB
Volume
57
Category
Article
ISSN
1359-6454

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✦ Synopsis

Based on the principal of virtual work, we derive an equation that describes the balance between volume and interface stresses in a particulate two-phase nanocomposite belonging to the class of random heterogeneous materials. Extracting absolute values of interface stress requires precise measurement of residual-strain-free lattice parameters and determination of interface area as well as volume fractions of phases. We find a value of 3:5 AE 0:2 N m Γ€1 for the isotropic phase-boundary stress of the Ag/Ni interface and a value of 0:67 AE 0:1 N m Γ€1 for the grain-boundary stress of Ag. If we compare this value with literature values for Gd, Pd and Fe, it appears that grain-boundary stress linearly correlates with the melting temperature of those elements.

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