Thuy Nguyen

@article{montiel_1922,

title = {Effect of architecture disorder on the elastic response of two-dimensional lattice materials},

author = {Antoine Montiel and Thuy Nguyen and Cindy Rountree and Valérie Geertsen and Patrick Guenoun and Daniel Bonamy},

url = {https://journals.aps.org/pre/abstract/10.1103/PhysRevE.106.015004?ft=1},

year  = {2022},

date = {2022-07-01},

journal = {Physical Review E},

volume = {106},

number = {1},

pages = {015004},

abstract = {We examine how disordering joint position influences the linear elastic behavior of lattice materials via numerical simulations in two-dimensional beam networks. Three distinct initial crystalline geometries are selected as representative of mechanically isotropic materials with low connectivity, mechanically isotropic materials with high connectivity, and mechanically anisotropic materials with intermediate connectivity. Introducing disorder generates spatial fluctuations in the elasticity tensor at the local (joint) scale. Proper coarse-graining reveals a well-defined continuum-level scale elasticity tensor. Increasing disorder aids in making initially anisotropic materials more isotropic. The disorder impact on the material stiffness depends on the lattice connectivity: Increasing the disorder softens lattices with high connectivity and stiffens those with low connectivity, without modifying the scaling between elastic modulus and density (linear scaling for high connectivity and cubic scaling for low connectivity). Introducing disorder in lattices with intermediate fixed connectivity reveals both scaling: the linear scaling occurs for low density, the cubic one at high density, and the crossover density increases with disorder. Contrary to classical formulations, this work demonstrates that connectivity is not the sole parameter governing elastic modulus scaling. It offers a promising route to access novel mechanical properties in lattice materials via disordering the architectures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nguyen_1496,

title = {Role of the Crystal Lattice Structure in Predicting Fracture Toughness},

author = {Thuy Nguyen and Daniel Bonamy},

url = {https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.205503},

year  = {2019},

date = {2019-11-01},

journal = {Physical Review Letters},

volume = {123},

number = {20},

pages = {205503},

abstract = {We examine the atomistic scale dependence of a material's resistance to failure by numerical simulations and analytical analysis in electrical analogs of brittle crystals. We show that fracture toughness depends on the lattice geometry in a way incompatible with Griffith's relationship between fracture and free surface energy. Its value finds its origin in the matching between the continuum displacement field at the engineering scale, and the discrete nature of solids at the atomic scale. The generic asymptotic form taken by this field near the crack tip provides a solution for this matching, and subsequently a way to predict toughness from the atomistic parameters with application to graphene},

keywords = {},

pubstate = {published},

tppubtype = {article}

}