Three Dimensional Variable Constraint Effects in Fracture Initiation
Abstract
Many naturally occurring cracks are three dimensional and cannot be evaluated using numerical techniques derived using two dimensional simplifications. The high stress and strain levels experienced in modern high toughness alloys prior to fracture require means to accurately simulate the nonlinear response of ductile materials in this regime. An accurate constitutive representation must be combined with a fracture criterion which is valid for the high strain regime to achieve accurate computerized simulations of fracture and near fracture behavior. In the current work, nonlinear numerical simulations are performed to determine the global and local responses of two surface cracked plates of HY-100 steel with varying crack propagation and crack depths. Failure is defined by a local fracture criterion using strain energy density. Differences in constraint along the crack perimeter are taken into account by recognizing the stress-strain history dependence of the critical strain energy density. Crack growth patterns determined from the numerical simulations accurately reflect experimental observations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 25, 1991
- Accession Number
- ADA233386
Entities
People
- V. G. Degiorgi
Organizations
- United States Naval Research Laboratory