Non-local plasticity effects on notch fracture mechanics
Abstract
We investigate the influence of gradient-enhanced dislocation hardening on the mechanics of notch-induced failure. The role of geometrically necessary dislocations (GNDs) in enhancing cracking is assessed by means of a mechanism-based strain gradient plasticity theory. Both stationary and propagating cracks from notch-like defects are investigated through the finite element method. A cohesive zone formulation incorporating monotonic and cyclic damage contributions is employed to address both loading conditions. Computations are performed for a very wide range of length scale parameters and numerous geometries are addressed, covering the main types of notches. Results reveal a strong influence of the plastic strain gradients in all the scenarios considered. Transitional combinations of notch angle, radius and length scale parameter are identified that establish the regimes of GNDs-relevance, laying the foundations for the rational application of gradient plasticity models in damage assessment of notched components.
Keywords
Cite
@article{arxiv.1709.08412,
title = {Non-local plasticity effects on notch fracture mechanics},
author = {Emilio Martínez-Pañeda and Susana del Busto and Covadonga Betegón},
journal= {arXiv preprint arXiv:1709.08412},
year = {2017}
}