Lecture

Bespoke Elasticity: Designing Architectured Materials with Nonlinear Properties

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Description

This lecture discusses the design of architectured materials with elastic energy closely approximating specified continuous functions. It begins by addressing the feasibility of such designs in one dimension, referencing earlier work that demonstrates this possibility. The instructor then transitions to two-dimensional scenarios, exploring the use of concentric helical lattices as springs in layered rectangular lattices. The mathematical foundation is established through the Stone-Weierstrass theorem, which supports the approximation of polynomial energies. The lecture further delves into the implications of Cauchy's relations in nonlinear elasticity, highlighting the significance of energies that can be approximated by pair potentials. The conclusion emphasizes that while the construction is optimal for certain energies, practical challenges remain in designing interpenetrating lattices. Overall, the lecture provides a comprehensive overview of the theoretical and practical aspects of bespoke elasticity in material design.

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Related concepts (32)

Elasticity (physics)

In physics and materials science, elasticity is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed. Solid objects will deform when adequate loads are applied to them; if the material is elastic, the object will return to its initial shape and size after removal. This is in contrast to plasticity, in which the object fails to do so and instead remains in its deformed state. The physical reasons for elastic behavior can be quite different for different materials.

Applied mechanics

Applied mechanics is the branch of science concerned with the motion of any substance that can be experienced or perceived by humans without the help of instruments. In short, when mechanics concepts surpass being theoretical and are applied and executed, general mechanics becomes applied mechanics. It is this stark difference that makes applied mechanics an essential understanding for practical everyday life.

Price elasticity of demand

A good's price elasticity of demand (, PED) is a measure of how sensitive the quantity demanded is to its price. When the price rises, quantity demanded falls for almost any good, but it falls more for some than for others. The price elasticity gives the percentage change in quantity demanded when there is a one percent increase in price, holding everything else constant. If the elasticity is −2, that means a one percent price rise leads to a two percent decline in quantity demanded.

Linear elasticity

Linear elasticity is a mathematical model of how solid objects deform and become internally stressed due to prescribed loading conditions. It is a simplification of the more general nonlinear theory of elasticity and a branch of continuum mechanics. The fundamental "linearizing" assumptions of linear elasticity are: infinitesimal strains or "small" deformations (or strains) and linear relationships between the components of stress and strain. In addition linear elasticity is valid only for stress states that do not produce yielding.

Finite strain theory

In continuum mechanics, the finite strain theory—also called large strain theory, or large deformation theory—deals with deformations in which strains and/or rotations are large enough to invalidate assumptions inherent in infinitesimal strain theory. In this case, the undeformed and deformed configurations of the continuum are significantly different, requiring a clear distinction between them. This is commonly the case with elastomers, plastically-deforming materials and other fluids and biological soft tissue.

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