| 摘要 |
PURPOSE: A fatigue test method is provided to accurately detect crack using elastic waves in the durability evaluation of an actual part of steel for a vehicle. CONSTITUTION: A fatigue test method is as follows. Specimen is fixed to a fixture. Ultrasonic waves are applied to the specimen(S310). A test condition that an operator wants is input through a computer(S320). A cylinder operates by controlling the inflow of oil according to the test condition of the operator(S330). It is transferred through an elastic-wave measuring device to the computer(S340). Whether the elastic wave measured with the elastic-wave measuring device has an amplitude higher than a predetermined threshold is verified(S350). Whether the measured elastic wave is maintained above a predetermined sustain time is verified(S360). The specimen is determined to be in a fatigue crack state if the measured elastic wave has an amplitude higher than the threshold above a predetermined sustain time(S370). |
