IMPACT FRAGMENTATION OF BRITTLE MATERIALS

The Breaking of Brittle Materials

A long metal thread breaks more easily than a short one—an observation Leonardo da Vinci made in the 15th century. It all comes down to simple statistics: the larger an object, the more likely it is to contain a region that breaks when subject to stress. The fracture properties of brittle materials also depend on the disorder in their underlying structure: a homogeneous material like glass brea...

Single and multiple fragmentation of brittle geomaterials

UWFDM-1149 Dynamic Fragmentation of Brittle Materials: Analytical Mechanics-Based Models

Two analytical mechanics-based models of dynamic fragmentation in brittle materials are proposed and solved to predict fragment size and time to fragmentation onset in terms of fundamental material properties and the applied strain rate. Previous widely-adopted analytical models of dynamic fragmentation are based on relatively simple energy balance arguments, and assume that the fragmentation e...

Dynamic buckling and fragmentation in brittle rods.

We present experiments on the dynamic buckling and fragmentation of slender rods axially impacted by a projectile. By combining the results of Saint-Venant and elastic beam theory, we derive a preferred wavelength lambda for the buckling instability, and experimentally verify the resulting scaling law for a range of materials including teflon, dry pasta, glass, and steel. For brittle materials,...

Crack initiation in brittle materials

In this paper we study the crack initiation in a hyper-elastic body governed by a Griffith’s type energy. We prove that, during a load process through a time dependent boundary datum of the type t → tg(x) and in absence of strong singularities (this is the case of homogeneous isotropic materials) the crack initiation is brutal, i.e., a big crack appears after a positive time ti > 0. On the cont...