Analytical solutions of a spherical nanoinhomogeneity under far-field unidirectional loading based on Steigmann–Ogden surface model

Abstract

For a solid surface or interface that is subjected to transverse loading, the influence of its flexural resistibility to bending deformation becomes significant. A spherical inhomogeneity or void embedded in an infinite elastic medium under the application of nonhydrostatic loads represents a typical example. In this work, we consider the most fundamental loading of a far-field unidirectional tension. Analytical displacements and stresses are developed by the coupling of a Steigmann–Ogden surface mechanical model, the simple method of Boussinesq displacement potentials, the semi-inverse method of elasticity, and Legendre series representations of spherical harmonics. The problem is then solved by converting the equilibrium equations of displacement into a linear system with respect to the Legendre series coefficients. The developed solutions are general in the sense that they may reduce to their classical or Gurtin–Murdoch counterparts as special cases. Analytical expressions reveal that the derived solution depends on four dimensionless ratios from among surface material parameters, shear moduli ratio, and inhomogeneity or void radius. In particular, instead of depending on both flexural parameters in the moment–curvature relation, one fixed combination is sufficient to represent the surface flexural rigidity. This is in contrast with the influence of the in-plane elastic stiffness, in which both surface Lamé parameters matter. Parametric studies further demonstrate that, for metallic inhomogeneities or voids with radii between 10 nm and 100 nm, the effects of surface flexural rigidity on stress distributions and stress concentrations are significant.

Anisotropic imperfect interface in elastic particulate composite with initial stress

“…In the context of particulate composites with spherical reinforcements, analytical solutions for a single spherical particle with the G–M interface were obtained and used to model the elastic fields [33–37] and effective properties [10, 38, 39] of particulate nanocomposites. Similar solutions for the S–O interfaces are reported in [40–44]. More advanced, finite-cluster [45] and representative unit cell [46] models of spherical particle composite with the G–M interface have been developed.…”

A problem for a material surface attached to the boundary of an elastic semi-plane

“…which coincides with equation (32) where G(x) is set to be identically zero. The functions Q(t, x) and B(x) are defined as before by formulas ( 33)- (40).…”

“…Eremeyev and Lebedev [18] derived the boundary conditions for the Steigmann-Ogden model and studied the existence and uniqueness of the solutions in certain spaces. The Steigmann-Ogden and the Gurtin-Murdoch theories have been used to study fracture [19][20][21][22][23][24][25][26][27], contact and patch-loading problems [28][29][30][31][32][33][34][35][36][37][38][39], particle and fiber reinforcements [40][41][42][43][44][45][46][47][48][49][50], and other topics [51][52][53][54][55][56][57][58][59][60][61][62][63]. The results are mostly available for the regular shapes of the boundaries of the solids such as straight, circular, or spherical.…”

Homogenization of Composites with Extended General interfaces: Comprehensive Review and Unified Modeling

“…Gao et al [525] studied the curvature-dependence of the interfacial energy and formulated interfacial energy together with an interface stress model resulting in a micromechanical framework to determine the overall elastic properties, see also Ref. [594]. Further analytical studies on the subject of the overall behavior of heterogeneous materials embedding elastic interfaces can be found in Refs.…”