Spatially resolved roughness exponent in polymer fracture

The fracture surface of slow and continuous crack propagation during environmental stress cracking of a semicrystalline polyethylene exhibits isotropic roughness exponents at the local scale but resolved across the macroscopic fracture surface a clear position dependence is found. The spatially resolved roughness exponent admits values in the range between 0.1 and 0.4, demonstrating nontrivial exponents in the small length-scale regime. Instead, they vary across the fracture surface according to the stress-state distribution, which suggests that the exponents are intimately linked to the locally dominating dissipation processes during craze cracking.

Automated summary

The fracture surface of a semicrystalline polyethylene during environmental stress cracking exhibits isotropic roughness at the local scale but clear position dependence at the macroscopic scale. The roughness exponent varies in the range of 0.1 to 0.4, indicating non-trivial exponents in the small length-scale regime. The variation of the exponent suggests a link to the dominating dissipation processes during craze cracking.