Detection of Fatigue Damage in Crankshafts with the Gel Electrode
930409
03/01/1993
- Event
- Content
- During fatigue testing of prototype austempered ductile iron crankshafts, cracks formed along crankpin fillets. These cracks were not detected by the conventional magnetic particle method but were readily imaged by a modified version of the gel electrode technique. The crankshaft was coated with a thin (∼0.5 μm) polymer film, either prior to, or after, the fatigue test. When the surface was subsequently inspected with a gel electrode probe, an impressed current from the probe flowed preferentially to the fatigue sites. Information is displayed in two formats:
-
(i)
qualitatively as a direct image of the fatigue sites, and
-
(ii)
quantitatively as the spatial distribution of charge flow to the surface. Both the primary fatigue cracks and a distribution of secondary sites of less severe fatigue damage were detected. The cracks formed near the edges of a fillet while the root of a fillet developed primarily secondary fatigue damage.
-
(i)
- Pages
- 14
- Citation
- Baxter, W., "Detection of Fatigue Damage in Crankshafts with the Gel Electrode," SAE Technical Paper 930409, 1993, https://doi.org/10.4271/930409.