Numerical simulations of dynamic interface crack growth
- Univ. of California, Santa Barbara, CA (United States)
- Brown Univ., Providence, RI (United States)
Dynamic interface crack growth is analyzed numerically using a framework in which separate constitutive relations are specified for the material phases and a set of cohesive surfaces. The constitutive law for the materials on each side of the bond line is that of an isotropic hyperelastic solid. An elastic relation between tractions and displacement jumps characterizes the cohesive surfaces, which include the bond line. The cohesive surface constitutive relation allows for the creation of new free surface and introduces a characteristic length into the formulation. The resistance to crack initiation, the crack speed history and crack growth off the interface are predicted without involving any ad hoc failure or crack kinking criteria. Full finite strain transient analyses are carried out for a plane strain bimaterial block with an initial central interface crack. Two types of loading are considered; tensile loading on one side of the specimen and crack face loading. The crack growth history and the evolution of the crack tip stress state are investigated for parameters characterizing a PMMA/Al bimaterial. When crack growth is confined to the interface, the crack speed can exceed the Rayleigh wave speed of PMMA. The mode mixity of the near tip fields is found to increase with increasing crack speed and large scale contact can occur in the vicinity of the crack tip. When the creation of new free surface is allowed in PMMA and aluminum, the crack speed at which attempted branching starts depends on the strength of the interface. Crack growth stays along a weak interface but kinks into PMMA from a strong interface as the crack speed increases. Additionally, the separate effects of elastic modulus mismatch and elastic wave speed mismatch on crack growth along an interface are explored for various PMMA artificial material combinations.
- OSTI ID:
- 175182
- Report Number(s):
- CONF-950686--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fatigue crack growth at arbitrary angles to bimaterial interfaces
A Fracture Mechanics Study of a Strong Interface: The Silicon/Glass Anodic Bond. Ph.D. Thesis