| 摘要 |
<P>PROBLEM TO BE SOLVED: To non-destructively evaluate a fatigue damage progress behavior during a high cycle fatigue test at a liquid nitrogen temperature (77 K) and to evaluate the occurrence of fatigue damage, a progress mechanism, and crack occurrence like in addition to fracture life. <P>SOLUTION: Liquid surface height of liquid nitrogen is controlled, vibrations of a specimen end part in a cryostat in which mist is prevented from penetrating into a laser optical path are detected by a laser vibration meter, a continuous waveform is recorded, and a nonlinear ultrasonic wave and AE are simultaneously analyzed. <P>COPYRIGHT: (C)2013,JPO&INPIT |
