A model to quantify fatigue crack growth by cyclic damage accumulation calculated by strip-yield procedures

Elber's hypothesis that  Keff can be assumed as the driving force for fatigue crack growth (FCG) is the basis for strip-yield models widely used to predict fatigue lives under variable amplitude loads, although it does not explain all load sequence effects observed in practice. To verify if th...

Full description

Saved in:
Bibliographic Details
Main Authors: Samuel Elias Ferreira, Jaime Tupiassú Pinho de Castro, Marco Antonio Meggiolaro
Format: Article
Language:English
Published: Gruppo Italiano Frattura 2017-07-01
Series:Fracture and Structural Integrity
Subjects:
Online Access:http://www.gruppofrattura.it/pdf/rivista/numero41/numero_41_art_18.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Elber's hypothesis that  Keff can be assumed as the driving force for fatigue crack growth (FCG) is the basis for strip-yield models widely used to predict fatigue lives under variable amplitude loads, although it does not explain all load sequence effects observed in practice. To verify if these models are indeed intrinsically better, the mechanics of a typical strip-yield model is used to predict FCG rates based both on Elber's ideas and on the alternative view that FCG is instead due to damage accumulation induced by the cyclic strain history ahead of the crack tip, which does not need or use  Keff ideas. The main purpose here is to predict FCG using the cyclic strains induced by the plastic displacements calculated by strip-yield procedures, assuming there are strain limits associated both the with the FCG threshold and with the material toughness. Despite based on conflicting principles, both models can reproduce quite well FCG data, a somewhat surprising result that deserves to be carefully analyzed.
ISSN:1971-8993
1971-8993