Dynamic crack growth along heterogeneous planar interfaces: interaction with unidimensional strips

TL;DR

This paper investigates the dynamic propagation of cracks along heterogeneous planar interfaces with periodically varying toughness, revealing the role of front waves and their influence on crack speed and behavior.

Contribution

It provides a theoretical and numerical analysis of crack dynamics along unidimensional toughness-modulated strips, highlighting the formation of front waves and their impact.

Findings

Front waves transport disturbances at speeds below Rayleigh wave speed.

Standing front waves influence local crack front speed.

Analytical results show dependence on strip wavelength, toughness contrast, and crack speed.

Abstract

We examine theoretically and numerically fast propagation of a tensile crack along unidimensional strips with periodically evolving toughness. In such dynamic fracture regimes, crack front waves form and transport front disturbances along the crack edge at speed less than the Rayleigh wave speed and depending on the crack speed. In this configuration, standing front waves dictate the spatio-temporal evolution of the local crack front speed, which takes a specific scaling form. Analytical examination of both the short-time and long-time limits of the problem reveals the parameter dependency with strip wavelength, toughness contrast and overall fracture speed. Implications and generalization to unidimensional strips of arbitrary shape are lastly discussed.