Non-local plasticity effects on fracture toughness

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearch

Abstract

The Mode I fracture strength in a nonlocal elastic-plastic material is analyzed under quasi-static steady crack growth. The plastic deformations are modelled using a constitutive model, where nonlocal plasticity effects are included in the instantaneous hardening moduli through a gradient measure of the effective plastic strain. Fracture is modelled by a cohesive zone criterion. Results on the numerically obtained stress fields are presented, as well as results on the steady-state fracture toughness. It is shown that the nonlocal theory predicts lower steady-state fracture toughness compared to predictions by conventional J2-flow theory, since higher normal stresses in front of the crack tip are predicted. Furthermore, the nonlocal material description increases the range of applicability of the cohesive zone model, since steady-state crack growth is possible for significantly larger values of the maximum stress in the traction-separation law normalised by the yield stress.
Original languageEnglish
Title of host publicationProceedings of Plasticity ´02: Plasticity, Damage and Fracture at Macro, Micro and Nano Scales
PublisherNEAT Press
Publication date2002
Publication statusPublished - 2002
EventPlasticity, Damage and Fracture at Macro, Micro and Nano Scales - Fulton, MD
Duration: 3 Jan 20029 Jan 2002

Conference

ConferencePlasticity, Damage and Fracture at Macro, Micro and Nano Scales
CityFulton, MD
Period03/01/200209/01/2002

Cite this

Niordson, C. F. (2002). Non-local plasticity effects on fracture toughness. In Proceedings of Plasticity ´02: Plasticity, Damage and Fracture at Macro, Micro and Nano Scales NEAT Press.