The effects of loading conditions, specimen size and metal particle size on the crack growth resistance curve (R-curve) and residual strength of a ceramic-metal functionally graded material (FGM) are studied based on the crack-bridging concept. It is found that the FGM exhibits strong R-curve behavior when a crack grows from the ceramic-rich region toward the metal-rich region and the residual ...

Experimentally determined T ε and CTOA resistance curves were used to simulate numerically, stable crack growth and the ensuing crack linkup in 0.8 mm thick 2024-T3 aluminum tension specimen with multiple site damage (MSD) subjected to monotonically/cyclically increasing loading. The T ε integral correctly predicted the crack growth and linkup history as well as the onset of rapid fracture in M...

This paper deals with the effect of several residual stress profiles on the fatigue crack propagation in prestressing steel wires subjected to tension loading or bending moment. To this end, a computer program was developed to evaluate the crack front evolution on the basis of the Walker law. Results demonstrate that the absence of residual stresses makes the crack propagate towards a preferent...

Fatigue crack propagation under tension-tension loading is observed in ( I trunsjormcition-tougheried purtiully stabilized zirconia (PSZ) certimic wnt~iining 9 mol% M g O . Such subcritical crack p m v t h behavior is clernonstrciterl to be licully induced, based on u comparison with behuvior unrler ,sirstciinerl loading (ut the maximum loud in thejiitigue cycle) and at varying c~clic~,fi-riluc...

In an earlier paper it was suggested that a knowledge of the elastic-stress variation in the neighborhood of an angular corner of an infinite plate would perhaps be of value in analyzing the stress distribution at the base of a V-notch. As a part of a more general study, the specific case of a zero-angle notch, or crack, was carried out to supplement results obtained by other investigators. Thi...

X-ray absorption microtomography loses considerable sensitivity when it is applied to samples with high-aspect-ratio cross-sections, e.g. plates or compact tension samples. Synchrotron X-ray phase enhanced imaging is much more sensitive than absorption-based techniques to cracks with small openings, and phase imaging and stereometric techniques are developed in this paper for three-dimensional ...

The difference in delamination onset predictions based on the type and location of the assumed initial damage are compared in a specimen consisting of a tapered flange laminate bonded to a skin laminate. From previous experimental work, the damage was identified to consist of a matrix crack in the top skin layer followed by a delamination between the top and second skin layer (+45o/-45o interfa...

present work shows the numerical determination of fatigue crack opening and closure stress intensity factors of a C(T) specimen under variable amplitude loading using a finite element method. A half compact tension C(T) specimen, assuming plane stress constraint was used by finite element method covering the effects in two-dimensional (2D) small scale yielding models of fatigue crack growth und...

We calculate the effect of the nonsingular stress acting parallel to a crack (the “Tstress”) on edge dislocation nucleation at a crack loaded in Mode I. We find that this leads to crack size effect – that is, for small cracks (of order 100 atomic spacings or less), the T stress causes the critical load for dislocation nucleation (expressed in terms of the applied stress intensity factor) to dev...