NONDESTRUCTIVE EVALUATION OF METAL FATIGUE.
SOUTHWEST RESEARCH INST SAN ANTONIO TEX
Pagination or Media Count:
A nondestructive testing device was developed to monitor the progress of fatigue growth in a rod type fatigue specimen stress cycled in direct tension. The technique developed was that of using a Hall-effect element to monitor the per turbations in the magnetic field at the surface of the specimen when the specimen was magnetized. Both longitudinal and radial flux orientations in the specimen are possible with the system developed under this contract. Typical inspection records taken with longitudinal flux orientation are presented. Preliminary tests were made to determine the repeatability and sensitivity of the system. Author