Multi-axial fatigue numerical crack propagation in cruciform specimens

Redesigning axial-axial (biaxial) cruciform specimens for very high cycle fatigue ultrasonic testing machines

The necessity to increase performances in terms of lifetime and security in mechanical components or structures is the motivation for intense research in fatigue. Applications range from aeronautics to medical devices. With the development of new materials, there is no longer a fatigue limit in the classical sense, where it was accepted that the fatigue limit is the stress level such that there...

Transient Crack Propagation in Asymmetric Cruciform Paths

The problem of two cracks emanating from the same origin and propagating asymmetrically at different velocities in an elastic and isotropic solid is treated in this paper. An unbounded and otherwise undisturbed medium and a constant anti-plane loading at infinity were assumed. Techniques of self-similar elastodynamics were utilized in conjunction with analytic-function theory. Since a closed-fo...

Fatigue crack propagation in microcapsule - toughened epoxy

The addition of liquid-filled urea-formaldehyde (UF) microcapsules to an epoxy matrix leads to significant reduction in fatigue crack growth rate and corresponding increase in fatigue life. Mode-I fatigue crack propagation is measured using a tapered doublecantilever beam (TDCB) specimen for a range of microcapsule concentrations and sizes: 0, 5, 10, and 20% by weight and 50, 180, and 460 lm di...

High Temperature Fatigue Crack Propagation in INCONEL718

Stochastic modeling of fatigue crack propagation

This paper presents a stochastic model of fatigue-induced crack propagation in metallic materials. The crack growth rate predicted by the model is guaranteed to be non-negative. The model structure is built upon the underlying principle of Karhunen±Lo eve expansion and does not require solutions of stochastic di€erential equations in either Wiener integral or Itô integral setting. As such this ...