Detection of Fatigue Damage Prior Crack Initiation with Scanning SQUID Microscopy

Journal Article · Mon Mar 06 00:00:00 EST 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2184685· OSTI ID:20798229

Lee, Tae-Kyu; Morris, Jr, J W ^[1]; Lee, Seungkyun; Clarke, John ^[2]

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1. Department of Materials Science and Engineering, University of California, Berkeley, CA 94720 (United States)
2. Department of Physics, University of California, Berkeley, CA 94720 (United States)

The remanence fields of fatigued ferritic steel specimens were measured using a scanning microscope based on a high transition temperature superconducting quantum interference device (SQUID). The results show an overall increase of remanence until dislocation density saturates and an additional local remanence increase after saturation during cyclic loading. Because of the combined magnetic and spatial resolution of the SQUID microscope, these local changes of dislocation structures can be detected before a crack actually initiates, and identify the sites where crack nucleation will occur.

• OSTI ID: 20798229
• Journal Information: AIP Conference Proceedings, Vol. 820, Issue 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Brunswick, ME (United States), 31 Jul - 5 Aug 2005; Other Information: DOI: 10.1063/1.2184685; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRACKS
DISLOCATIONS
FATIGUE
FERRITIC STEELS
MICROSCOPES
NONDESTRUCTIVE TESTING
SQUID DEVICES
TRANSITION TEMPERATURE