SYMPOSIA PAPER Published: 01 January 1988
STP23268S

An Elastic-Plastic Finite-Element Analysis of the -Resistance Curve Using a CTOD Criterion

Source

The tentative test procedure for determining J-R curves (crack-growth resistance curves based on the J-integral) on compact and three-point bend specimens showed a discrepancy between specimen types: the bend specimen gave a higher J-R curve than the compact specimen. The purpose of this paper is to investigate this discrepancy, numerically, by simulating the fracture process on compact and bend specimens using a two-dimensional finite-element analysis and a critical crack-tip opening displacement (CTOD) criterion.

An elastic-plastic (incremental and small strain) finite-element analysis was used with the critical CTOD criterion to model stable crack growth in compact specimens made of HY-130 steel. A combined analysis between plane-stress and plane-strain conditions was found to simulate the fracture process quite well. In the combined analysis, plane-strain conditions were imposed around the crack tip while plane-stress conditions were imposed elsewhere. The same analysis was then used to predict stable crack growth behavior of bend specimens. J-R curves were then calculated from the numerical results for each specimen type using several different methods. In general, the J-R curves obtained from the bend specimens were higher than those obtained from the compact specimens, especially beyond maximum load. Up to maximum load, however, the modified deformation theory of plasticity J*D and the contour-integral JΓ methods gave essentially the same J-R curves for both specimen types.

Author Information

Newman, JC
NASA Langley Research Center, Hampton, VA
Booth, BC
The Johns Hopkins University, Baltimore, MD
Shivakumar, KN
Analytical Services and Materials, Inc., Hampton, VA
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E08
Pages: 665–685
DOI: 10.1520/STP23268S
ISBN-EB: 978-0-8031-5036-2
ISBN-13: 978-0-8031-0949-0