Continuum and Micromechanics Treatment of Constraint in Fracture
Abstract
This report explores the fundamental concepts of the J-Q description of crack-tip fields, the fracture toughness locus and micromechanics approaches to predict the variability of macroscopic fracture toughness with constraint under elastic-plastic conditions. While these concepts derived from plane-strain considerations, initial applications in fully 3D geometries are very promising. Computational results are presented for a surface cracked plate containing a 6:1 semi-elliptical, a=tl4 flaw subjected to remote uniaxial and biaxial tension. Crack-tip stress fields consistent with the J-Q theory are demonstrated to exit at each location along the crack front. The micromechanics model employs the J-Q description of crack-front stress to interpret fracture toughness values measured on laboratory specimens for fracture assessment of the surface cracked plate. The computational results suggest only a minor effect of the biaxial loading on the crack tip stress fields and, consequently, on the propensity for fracture relative to the uniaxial loading.... J-integral, Q-stress, Fracture toughness, Surface flaw biaxial loading, Finite element analysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1993
- Accession Number
- ADA260927
Entities
People
- C. F. Shih
- R. H. Dodds Jr.
- Ted L. Anderson
Organizations
- University of Illinois Urbana–Champaign