Cyclic Loading Fatigue - Caused by either cyclic pressure loadings or cyclic stress, ie all pressurized areas of an aircraft, the landing gear, engine disks
Sonic Effects - Fatigue caused by the pressure differences due to sonic pressure waves, can be found in engine inlet cowls, areas adjacent to the engine that have thin metal. Usually only thin structure affected by this. The exception would be turbine blades and vanes.
Thermal Effects - Fatigue due to the cyclic expansion and contraction or material due to heat loss or gain. Brakes are a good example, as are any turbine component.
Corrosion Fatigue - Material Failure due to a tensile stress and corrosive environent. Both the stress and corrosive environment must be present for this to happen. Most likely found in 6000 or 7000 series aluminum or high strength steel components on aircraft.
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