Show simple item record

dc.contributor.advisorChallenger, K.D.
dc.contributor.authorKamen, John S.
dc.dateJune 1983
dc.date.accessioned2012-11-19T23:58:28Z
dc.date.available2012-11-19T23:58:28Z
dc.date.issued1983-06
dc.identifier.urihttp://hdl.handle.net/10945/19770
dc.description.abstractThe effects of the environment and dwell periods on fatigue crack growth rates at 525°C for both annealed and normalized and tempered 2 1/4 Cr - 1 Mo steel in High Strain Fatigue (HSF) and Linear Elastic Fracture Mechanics (LEFM) regimes in air and in vacuum have been examined using optical and scanning electron microscopy techniques. Fatigue crack propagation rates were determined and were found to vary with the environment and the loading waveform used in the tests. At small crack depths in HSF, oxidation in air increased cyclic crack growth rates by over an order of magnitude compared with vacuum. For continuous cycling tests at a frequency of 0.01 Hz, and tests with a peak tension, compression, or tension plus compression dwell cycling, the rates were similar. The fastest crack growth in air occurred during cycles having both tension and compression dwell periods. Fractographs were analyzed in attempts to understand the reasons for the different propagation rates. Evidence suggesting partial rewelding of the crack surfaces during compressive dwell periods in vacuum and a change in fracture mode from transgranular to a branching "intergranular-like" fracture when the environment was changed from air to vacuum were observed.
dc.description.urihttp://archive.org/details/theeffectsofenvi1094519770
dc.language.isoen_US
dc.publisherMonterey, California. Naval Postgraduate Schoolen_US
dc.rightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
dc.subject.lcshMechanical engineeringen_US
dc.titleThe effects of environment and dwell on high temperature fatigue crack growth of 2 1/4 Cr - 1 Mo steel.en_US
dc.typeThesisen_US
dc.contributor.secondreaderMcNelley, Terry R.
dc.contributor.corporateNaval Postgraduate School (U.S.)
dc.contributor.departmentMechanical Engineering
dc.subject.author2 1/4 Cr - ] Mo Steelen_US
dc.subject.authorcreep-fatigue interactionen_US
dc.subject.authorhigh temperature fatigue crack growthen_US
dc.subject.authorenvironment effects on fatigue crack growthen_US
dc.subject.authoroxidation effects on fatigue crack growthen_US
dc.description.serviceLieutenant, United States Navy
etd.thesisdegree.nameM.S. in Mechanical Engineeringen_US
etd.thesisdegree.levelMastersen_US
etd.thesisdegree.disciplineMechanical Engineeringen_US
etd.thesisdegree.grantorNaval Postgraduate Schoolen_US
dc.description.distributionstatementApproved for public release; distribution is unlimited.


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record