Affiliation:
1. Harbin Institute of Technology
2. Georgia Institute of Technology
Abstract
In the present paper, the relation between fatigue crack growth threshold and material’s
cyclic saturation behavior is investigated. The dislocation-free zone (DFZ) model is used to
determine the dislocation distribution ahead of the crack tip. A cohesive zone model is developed to
determine the stress field of the DFZ under cyclic loading. The effect of cyclic loading makes the
plastic zone hardening (or softening), which raises the stress level in DFZ, and may lead to fracture.
It is found that the near threshold characteristics are mostly determined by the cyclic deformation
behavior of the material, and might be theoretically determinable from the standard cyclic loading
test.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,General Materials Science