Lead Engineer-Technology, McDonnell Aircraft Company, St. Louis, Mo.
Aerospace Research Engineer, Structural Research Branch, Naval Air Development Center, Warminster, Pa.
Pages: 19 Published: Jan 1982
Recent research into the crack growth behavior of aircraft landing gear steels shows that combinations of aggressive chemical environment and high sustained loading can cause significant reduction in the fatigue crack growth life of 300M steel. Crack growth behaviors of 300M and HP 9-4-0.30 steels are compared for continuous salt water immersion and alternate immersion in synthetic sea water environments. An analysis approach which sums the crack growth due to cyclic loading in an inert environment is shown to accurately correlate and predict the combined effects of chemical environment and mechanical loading on crack growth. Crack growth behavior under landing gear stress spectra typical of Air Force and Navy usage is compared.
crack growth, steels, environmental acceleration, surface flaws, crack growth prediction, landing gear, spectrum loads
Paper ID: STP28862S