Investigation of fatigue crack growth under in-phase loading as well as phase-shifted loading using cruciform specimens

Crack path and fracture surface analysis of ultrasonic fatigue testing under multiaxial loadings

“…D. Infante-García et al [10] have found out that the bifurcation effect occurs when a 45º crack initiates in out-of-phase conditions. In their study, Wolf et al [11] presented a work with aluminium cruciform specimens where they found out a similar crack behaviour. Moreover, Avateffazeli M. and Haghshenas M., address in their work these topics and they are in consonance.…”

A new method for ultrasonic fatigue testing of equibiaxial and pure shear cruciform specimens

“…Considering the applied unitary biaxiality ratio, E. Lee and R. Tayler [26] showed that the initial crack path occurs at 45º. Wolf et al [27] observed similar crack behaviour in aluminium cruciform specimens with 45º degree initial path leading to a similar bifurcation. Figure 13 shows the two present crack locations, size, the damaged surface, as well as thermal imaging where slight heat generation can be seen at the failed fillet.…”

Cruciform specimens for the determination of crack growth behaviour in biaxial stress fields: calculation of K-factors

“…The chemical composition of both materials can be found in Ref. [21]. The stress-strain curves and selected mechanical properties of the investigated materials are given in Fig.…”

“…Refs. [14,15,20,21]). Subsequently, a simple model is developed to calculate the stress intensity factors for straight crack paths that grow parallel to one loading axis or with an angle of 45 • to both load axes.…”

“…The comparison of stress intensity factors calculated using Y fit (a) or Y fit y (a) with stress intensity factors of real crack paths computed by FE for the crack paths and crack tip coordinates, see Ref. [21] and Figs. 5c and 5d, also shows deviations of less than 3 %.…”