A method for determining the non-propagation threshold of fatigue cracks at high frequencies.

摘要

A method for determining a non-propagation threshold for fatigue cracks at high frequencies, wherein a cyclic load (32, 32A) is applied to at least one specimen having an oval hole (12) in the test zone (10A). The oval hole has a notch (14) at one end, the specimen is held between two rigid masses (24, 26), and two rigid prestress plates (20, 22) Placed on either side of at least one specimen and clamped to two rigid masses at the two ends (20A, 22A; 20B, 22B) of the plate, respectively, so that repeated loading causes fatigue cracks to arise from the notches At a frequency selected to be equal to the resonant frequency of the assembly comprising the specimen, mass, and stress plate, and then said that the crack has stopped propagating When observed, the final length of the crack is measured, a chart is used to determine the fatigue crack non-propagation threshold ΔKth, and cyclic loading is performed with the help of a rigid upright portion. Obtained by an electrodynamic vibrator pot that is rigidly clamped to the structure, including a thrust rod for supporting a rigid mass and transmitting a cyclic load to an assembly comprising a specimen, mass, and stress plate. Method.