This work proposes a methodology to compute fretting fatigue crack initiation and total life by iterative models calibrated with stress–strain-life curves. One of the main novelty such is assumption that length determined size critical distance. To separate propagation lives, numerical approach finite elements used. The incorporates not only multiaxial non-proportional characteristic stress fie...

As a first step towards a new crack healing methodology for cyclic loading, this paper examines two promising crack-tip shielding mechanisms during fatigue of a microcapsule toughened epoxy. Artificial crack closure is achieved by injecting precatalyzed monomer into the crack plane to form a polymer wedge at the crack tip. The effect of wedge geometry is also considered, as dictated by crack lo...

Abstract: To ensure the rail transportations safety, evaluation of fatigue behavior of the rail steel is necessary. High cycle fatigue behaviour of a rail steel was the subject of investigation in this research using fracture mechanics. Finite element method (FEM) was used for analyzing the distribution of the stresses on the rail, exerted by the external load. FEM analysis showed that the ...

In this work, the uniaxial and biaxial fatigue behaviour of maraging steel (18Ni300) obtained by additive manufacturing was studied. The material evaluated using several load paths different levels. predictive capacity life crack initiation angle critical plane methods Liu (I II), Chu, Conle, Bonnen (CCB) were evaluated. results showed that normal stresses had a strong effect on life. general, ...

The primary factors governing the behavior in the long lifetime regime of turbine engine materials are discussed. These factors are based on a study of fatigue lifetime distributions and underlying mechanisms in a number of materials, including titanium alloys, nickel-base superalloys, and  TiAl based alloys. A hypothesis of fatigue variability is described, and appears to explain the various ...

Commercial transport aircraft are required to operate under the concept of damage tolerance. Because of the structural redundancy and the crack arrest capability, the current fleet of commercial aircraft was initially designed to have sufficient residual strength to sustain discrete source damage. However, fatigue damage during the life of an aircraft can significantly reduce the residual stren...

Fatigue properties and cracking behavior of cold-drawn commercially pure aluminum wires (CPAWs) widely used as the overhead transmission conductors were investigated. It was found that the fracture surface of the CPAWs shows an obvious four-stage fracture characteristic, i.e., crack initiation, planar crack propagation, 45°-inclined crack propagation and final rapid fracture. The crack growth m...

In the present investigation, an attempt has been made to use “exponential model” in the prediction of fatigue life without integrating the fatigue crack growth rate curve (FCGR). The obtained results are compared with experimental crack growth data obtained for 2024-T351 aluminum alloy for four bending V-Charpy specimens under constant amplitude loading in stress ratio range from 0.1 to 0.3 an...

Abstract Crack initiation and propagation in a peroxide-cured polybutadiene rubber reinforced with silanised silica nanofiller were studied under cyclic loading condition. The fatigue properties of the semi-transparent samples tested at constant strain amplitude, test frequency temperature. Initiation subsequent growth cracks observed using an optical microscope as function number cycles until ...