Determination of fracture mechanics parameters J and C∗ by finite element and reference stress methods for a semi-elliptical flaw in a plate

Abstract

The fracture mechanics parameters J and C* used, respectively, to describe ductile fracture and creep crack growth can be determined either by finite element methods or reference stress techniques. In this paper solutions for a partially penetrating semielliptical flaw in a plate subjected to tension and bending loading are considered. Estimates of J and C* are obtained from finite element calculations for a range of work-hardening plasticity and power law creep behaviours and from reference stresses derived from 'global' collapse of the entire cracked cross-section. Comparisons are made with solutions taken from the literature for a range of loading conditions, plate geometries and crack sizes and shapes. Generally it is found that although there are significant variations between the different finite element solutions, satisfactory estimates of J and C* that are mostly conservative are obtained when the reference stress procedure is adopted.

Creep‐fracture resistance parameters determination based on stress and ductility damage models

“…He and Hutchinson obtained a solution to an infinite‐size creep‐cracked body. Moreover, a typical extensive creep solution to C* for different geometries of test specimens is widely available in literature, including corresponding standard‐test methods to determine the creep‐crack growth . However, most of these creep‐fracture‐mechanics parameters are focused only on different forms of the C ‐integral application, neglecting the coupling effect of creep damage on the crack‐tip stress or strain rate fields.…”

Evaluation of <i>J</i> Integral for Interacting Twin Collinear Through-Wall Cracks in a Plate under Tension

“…The interaction behaviour of structural components with multiple cracks under linear-elastic fracture mechanics condition has been widely studied [4][5][6][7][8][9] and some useful recommendations have been proposed for the integrity assessment of structures with multiple cracks [10][11][12]. For structures operated under elastic-plastic condition, the most of studies have been focused on the elastic-plastic analysis of the single crack.…”

A numerical creep analysis on the interaction of twin semi-elliptical cracks

“…However, for the structure operated under creep regime, most of studies are focused on the creep analysis of single semi-elliptical surface crack [13][14][15], and very little attention has been paid on the interaction of multiple semi-elliptical surface cracks.…”