PSI - Issue 13

Mihaela Iordachescu et al. / Procedia Structural Integrity 13 (2018) 584–589 M. Iordachescu, M. de Abreu, A. Valiente/ Structural Integrity Procedia 00 (2018) 000 – 000

589

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The simultaneous action of transverse compressive loading and fatigue tensile loading of 200 MPa stress range produces nominally infinite lifetime of the wires for combinations of the compressive and maximum tensile loads experimentally determined. These combinations can be roughly described as those given by compressive loads or maximum tensile fatigue loads higher than 50% of the tensile bearing capacity of the wire.

Fig. 4. a) Sketch of tensile/fatigue failure of wires under transverse load; b) macroscopic image of the LDS wire fracture in the T-QL test; c) ductile shear fracture morphology of broken wires subjected to T-QL; d) macroscopic image of the LDS wire fracture in the F-QL test; e) beach marks of shear fatigue fracture propagation on the wires broken under F-QL; f) Fatigue test results of LDS wires in the non-dimensional axial – transverse load diagram (Q - applied transverse compression load, P Fmax - maximum applied tensile fatigue load, P 0 - maximum load in tension)

Acknowledgements

The authors gratefully acknowledge the financial support obtained from the Spanish Ministry of Science and Innovation through the project BIA 2014-53314 – R and the collaboration with INOXFIL S.A. who kindly provided the high-strength, lean and duplex steel wires.

References

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