Stress corrosion cracks (SCC) in low-pressure steam turbine discs are serious hidden dangers to production safety in the power plants, and knowing the orientation and depth of the initial cracks is essential for the evaluation of the crack growth rate, propagation direction and working life of the turbine disc. In this paper, a method based on phased array ultrasonic transducer and artificial n...

Piezoelectric wafer active sensors can be applied to aging aircraft structures to monitor the onset and progress of structural damage such as fatigue cracks and corrosion. Two main detection strategies are considered: (a) the wave propagation method for far-field damage detection; and (b) the electro-mechanical (E/M) impedance method for near-field damage detection. These methods are developed ...

Fatigue crack initiation and early short crack propagation behaviour in two microstructural variants of a recently developed Low Solvus, High Refractory (LSHR) disc superalloy at room temperature has been investigated by three-point bending with replication procedure. The results shows that fine gained (FG) LSHR possesses higher fatigue life due to its better crack initiation resistance, limite...

This paper investigates the directional stability of crack propagation in adhesively bonded joints. First, an analytical model analyzing the energy balance during the crack propagation in double cantilever beam (DCB) specimens is presented, and the directional stability of cracks is predicted. The results are consistent with the analytical predictions made by Fleck, Hutchinson, and Suo [1] usin...

The interaction between cracks, as well their propagation, in single-crystal aluminum was simulated at the atomic scale by molecular dynamics method and modified embedded atom method. Further, effects of distance two cracks difference crack size on propagation mechanical properties were comprehensively investigated. results demonstrated that multi-crack is a quite complex process, which accompa...

Fracture toughness resistance curves describe a material's resistance against crack propagation. These curves are often used to characterize biomaterials like bone, nacre or dentin as these materials commonly exhibit a pronounced increase in fracture toughness with crack extension due to co-acting mechanisms such as crack bridging, crack deflection and microcracking. The knowledge of appropriat...