In materials science, fatigue is the initiation and propagation of cracks in a material due to cyclic loading. Once a fatigue crack has initiated, it grows a small amount with each loading cycle, typically producing striations on some parts of the fracture surface. If the loads are above a certain threshold, microscopic cracks will begin to initiate at stress concentrations such as holes, composite interfaces or grain boundaries in metals. Endurance (fatigue strength) – the property of a material or structure to resist failure or damage caused by fatigue.
