Dynamic buckling and fragmentation in brittle rods

TL;DR

This study investigates how slender brittle rods buckle and fragment under impact, deriving a preferred buckling wavelength and analyzing resulting fragment size distributions across various materials.

Contribution

The paper combines theoretical analysis with experiments to identify a preferred buckling wavelength and links buckling patterns to fragmentation in brittle rods.

Findings

Derived a scaling law for buckling wavelength across materials.

Observed fragment size distributions with peaks near lambda/2 and lambda/4.

Confirmed the influence of buckling on fragmentation patterns.

Abstract

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, buckling leads to the fragmentation of the rod. Measured fragment length distributions show two clear peaks near lambda/2 and lambda/4. The non-monotonic nature of the distributions reflect the influence of the deterministic buckling process on the more random fragmentation processes.