Evolution of dislocations and twins in high cycle fatigue of a twinning-induced plasticity steel

Dislocation Source and Pile-up in a Twinning-induced Plasticity Steel at High-Cycle Fatigue

“…Smooth dog-bone specimens with a thickness of 18.3 mm were machined by electrodischarge machining from the as-received steel plate. The sample geometry can be found elsewhere [23]. The large thickness avoids the bulking during tension-compression fatigue tests using an MTS Landmark2 fatigue machine.…”

“…Different to the investigations of strain hardening mechanism of TWIP steels under static tensile tests, studies on fatigue behaviour of TWIP steels are much less [21,22]. It has been reported that the fatigue limit of TWIP steels is close to the yield strength [21][22][23][24][25]. A TWIP steel subjected to high-cycle fatigue was studied [23], showing that very few deformation twins can be found during fatigue test, different to the static tensile tests.…”

“…It has been reported that the fatigue limit of TWIP steels is close to the yield strength [21][22][23][24][25]. A TWIP steel subjected to high-cycle fatigue was studied [23], showing that very few deformation twins can be found during fatigue test, different to the static tensile tests. Instead, dislocation cells are found at a stress amplitude lower than the yield stress during fatigue test [23].…”

“…A TWIP steel subjected to high-cycle fatigue was studied [23], showing that very few deformation twins can be found during fatigue test, different to the static tensile tests. Instead, dislocation cells are found at a stress amplitude lower than the yield stress during fatigue test [23]. Nevertheless, the dislocation sources and dislocation pile-ups during fatigue tests have not been discussed, which are important information for understanding the fatigue behaviour of the TWIP steel.…”

Co-Cr-Ni-Mo wires for medical applications : processing, mechanical, microstructure and fatigue characterization

“…As the magnitude of the frictional stress increases, the existing dislocations or the cracks need to apply higher flow stress to cross the debris, thus increasing the threshold intensity in the material. This contributed to a reduced crack propagation rate and increased fatigue resistance in the wire [400,401]. sample, subjected to a strain of 670MPa.…”