Some available experimental results for the ductile failure of plates with surface cracks under tension are reviewed. The response of crack driving force, J, and the ligament strain near the local and global limit loads are investigated by performing elastic-perfectly plastic finite element (FE) analysis of a plate with a semi-elliptical crack under tension. The results show that a ligament may survive until the global collapse load is reached when the average ligament strain at the global collapse load, which depends on the uniaxial strain corresponding to the flow stress of the material and the crack geometry, is less than the true fracture strain of the material obtained from uniaxial tension tests. The FE analysis shows that ligament yielding corresponding to the local limit load has little effect on J and the average ligament strain, whereas approach to global collapse corresponds to a sharp increase in both J and the average ligament strain. The prediction of the FE value of J using the reference stress method shows that the global limit load is more relevant to J-estimation than the local one.
[1]
I. W. Goodall,et al.
Theoretical determination of reference stress for partially penetrating flaws in plates
,
2001
.
[2]
Iradj Sattari-Far,et al.
Finite element analysis of limit loads for surface cracks in plates
,
1994
.
[3]
Hiroshi Tada,et al.
The stress analysis of cracks handbook
,
2000
.
[4]
A. G. Miller,et al.
Review of limit loads of structures containing defects
,
1988
.
[5]
Y. Lei.
J-integral and limit load analysis of semi-elliptical surface cracks in plates under tension
,
2004
.
[6]
Y. Lei,et al.
J-integral and limit load analysis of semi-elliptical surface cracks in plates under combined tension and bending
,
2004
.
[7]
Robert A. Ainsworth,et al.
The assessment of defects in structures of strain hardening material
,
1984
.
[8]
Do-Jun Shim,et al.
Approximate J estimates for tension-loaded plates with semi-elliptical surface cracks
,
2002
.