Abstract
In this paper the low cycle fatigue properties and cyclic fracture behavior of aluminum alloy 7150 are examined. Test specimens of the alloy were cycled using tension-compression loading, under total strain control, over a range of plastic strains giving lives of less than 10 4 cycles. The alloy displayed softening in both the longitudinal and transverse orientations of the wrought plate, at all cyclic strain amplitudes. The observed softening behavior is ascribed to contributions from concurrent and synergistic effects involving an interaction of mobile dislocations with matrix precipitates and multiple microscopic crack initiation leading to macroscopic crick growth. Fracture of the alloy samples was predominantly intergranular, for both orientations, with tortuous crack path. The low cycle fatigue properties and cyclic fracture behavior of the alloy are discussed in terms of competing influences of plastic strain amplitude, response stress, intrinsic microstructural effects, dislocation-microstructure interactions and matrix slip characteristics.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have