Fatigue behavior and structural stress analysis of coach-peel and lap-shear friction stir welded joints of AZ31 magnesium alloy

dc.contributorBarkey, Mark E.
dc.contributorGuo, Yuebin B.
dc.contributor.advisorJordon, J. Brian
dc.contributor.authorSheikh, Mohammed Haroon
dc.contributor.otherUniversity of Alabama Tuscaloosa
dc.date.accessioned2017-03-01T17:10:02Z
dc.date.available2017-03-01T17:10:02Z
dc.date.issued2014
dc.descriptionElectronic Thesis or Dissertationen_US
dc.description.abstractIn this work the fatigue behavior of coach-peel and lap-shear friction stir linear welded joints of AZ31 magnesium alloy sheet were evaluated under different loads and the results were compared using structural stress analysis. Lap-shear coupons of 30 mm in width were obtained from a welded overlap configuration. However, since coach-peel configuration coupons were not available, aluminum L-shaped brackets were adhesed weld to create the coach-peel configured specimen. The experimental fatigue life results showed an inverse relationship between applied load and the number of cycles to failure for both types of coupons. However, due to differences in the configuration of the joint leading to higher applied stress, coach-peel coupons failed at comparatively lower loads than lap-shear coupons. In order to correlate the fatigue data with stresses developed at the weld, finite element analysis, using shell/plate elements, was employed to model the joints under cyclic loading. The modeling effort focused on several post-process techniques including equivalent stress and structural stress methods. While the structural stress approach has merits over conventional nominal equivalent stress approach for welded joints including accuracy of the results and mesh insensitivity, it could not correlate the lap-shear and coach-peel fatigue results into a master design curve. As such, a fatigue damage parameter (FDP) was introduced to correlate the fatigue results of both the joints, thus establishing a basic relation to account for differences in stress at the weld for lap-shear and coach-peel welded configurations.en_US
dc.format.extent50 p.
dc.format.mediumelectronic
dc.format.mimetypeapplication/pdf
dc.identifier.otheru0015_0000001_0001661
dc.identifier.otherSheikh_alatus_0004M_11994
dc.identifier.urihttps://ir.ua.edu/handle/123456789/2112
dc.languageEnglish
dc.language.isoen_US
dc.publisherUniversity of Alabama Libraries
dc.relation.hasversionborn digital
dc.relation.ispartofThe University of Alabama Electronic Theses and Dissertations
dc.relation.ispartofThe University of Alabama Libraries Digital Collections
dc.rightsAll rights reserved by the author unless otherwise indicated.en_US
dc.subjectMechanical engineering
dc.titleFatigue behavior and structural stress analysis of coach-peel and lap-shear friction stir welded joints of AZ31 magnesium alloyen_US
dc.typethesis
dc.typetext
etdms.degree.departmentUniversity of Alabama. Department of Mechanical Engineering
etdms.degree.disciplineMechanical Engineering
etdms.degree.grantorThe University of Alabama
etdms.degree.levelmaster's
etdms.degree.nameM.S.
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
file_1.pdf
Size:
1.44 MB
Format:
Adobe Portable Document Format