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dc.contributor.authorZeitvogel, Daniel Tobiasen_US
dc.date.accessioned2013-01-17T21:21:02Z
dc.date.available2013-01-17T21:21:02Z
dc.date.issued2012-08-27en_US
dc.identifier.urihttp://hdl.handle.net/1853/45809
dc.description.abstractCold rolled carbon steel 1018C is widely used in pressurized fuel pipelines. For those structures, stress corrosion cracking (SCC) can pose a significant problem because cracks initiate late in the lifetime and often unexpectedly, but grow fast once they get started. To ensure a safe operation, it is crucial that any damage can be detected before the structural stability is reduced by large cracks. In the early stages of SCC, microstructural changes occur which increase the acoustic nonlinearity of the material. Therefore, an initially monochromatic Rayleigh wave is distorted and measurable higher harmonics are generated. Different levels of stress corrosion cracking is induced in five specimens. For each specimen, nonlinear ultrasonic measurements are performed before and after inducing the damage. For the measurements, oil coupled wedge transducers are used to generate and detect tone burst Rayleigh wave signals. The amplitudes of the received fundamental and second harmonic waves are measured at varying propagation distances to obtain a measure for the acoustic nonlinearity of the material. The results show a damage-dependent increase in nonlinearity for early stages of damage, indicating the suitability for this nonlinear ultrasonic method to detect stress corrosion cracking before structural failure.en_US
dc.publisherGeorgia Institute of Technologyen_US
dc.subjectNondestructive evaluationen_US
dc.subjectRayleigh wavesen_US
dc.subjectAcoustic surface wavesen_US
dc.subjectStructural testingen_US
dc.subject.lcshNondestructive testing
dc.subject.lcshUltrasonic testing
dc.subject.lcshUltrasonic waves
dc.subject.lcshUltrasonics
dc.subject.lcshStress corrosion
dc.subject.lcshMetals Fatigue
dc.subject.lcshMetals Corrosion fatigue
dc.titleCharacterization of damage due to stress corrosion cracking in carbon steel using nonlinear surface acoustic wavesen_US
dc.typeThesisen_US
dc.description.degreeMSen_US
dc.contributor.departmentCivil and Environmental Engineeringen_US
dc.description.advisorCommittee Chair: Jacobs, Laurence J.; Committee Member: Kim, Jin-Yeon; Committee Member: Qu, Jianminen_US


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