Fatigue tests at stresses producing failure in 2 to 10,000 cycles

Herbert F. Hardrath, Walter Illg
naca-tn-3132
Jan 1954


Notched specimens made of 24S-T3 and 75S-T6 aluminum-alloy sheet material, with theoretical stress-concentration factors equal to 4.0, were subjected to completely reversed axial loads. Failures occurred in less than 50 cycles at two-thirds of the static tensile strength and in as few as 2 cycles when the applied load was near the static strength of the specimen.

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