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arXiv · 1512.08089

Surface tension and the Mori-Tanaka theory of non-dilute soft composite solids

Francesco Mancarella·Robert W. Style·John S. Wettlaufer
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Abstract

Eshelby's theory is the foundation of composite mechanics, allowing calculation of the effective elastic moduli of composites from a knowledge of their microstructure. However it ignores interfacial stress and only applies to very dilute composites -- i.e. where any inclusions are widely spaced apart. Here, within the framework of the Mori-Tanaka multiphase approximation scheme, we extend Eshelby's theory to treat a composite with interfacial stress in the non-dilute limit. In particular we calculate the elastic moduli of composites comprised of a compliant, elastic solid hosting a non-dilute distribution of identical liquid droplets. The composite stiffness depends strongly on the ratio of the droplet size, $R$, to an elastocapillary length scale, $L$. Interfacial tension substantially impacts the effective elastic moduli of the composite when $R/L\lesssim 100$. When $R < 3L/2$ ($R=3L/2$) liquid inclusions stiffen (cloak the far-field signature of) the solid.

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Francesco Mancarella, Robert W. Style, John S. Wettlaufer. 2015-12-26. Surface tension and the Mori-Tanaka theory of non-dilute soft composite solids. https://doi.org/10.1098/rspa.2015.0853

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