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Residual stresses and fatigue performances at cold expanded fastener holesOzdemir, A. T. January 1993 (has links)
This work presents an investigation of the effect of cold-expansion methods on both residual stress distributions and fatigue life improvements in a high strength 7050 T76 aluminium alloy. Cold-expansion is usually achieved by the FTI split-sleeve process using commercially available equipment and prescribed levels of mandrel interference. A cold-expansion system has also been developed at the Open University which allows the degree of cold-expansion to be infinitely varied in a simple manner. The nature of residual stress distributions after the FTI split-sleeve and the Open University processes are evaluated by a mechanical (destructive) method based on Sachs boring-out technique. Since the Sachs method requires cylindrical specimens, 40mm diameter washers concentric with expanded holes have been produced from original rectangular specimens. To allow for any stress relaxation caused by washer manufacture, relevant compensation equations have been developed and are used to compensate the evaluated residual stresses after each Sachs experiment. It is revealed that residual hoop stresses produced by the FTI split-sleeve method are more compressive than that are produced by the Open University method. Residual hoop stress distributions are found to be unaxisymmetric and orientation dependent. In the FTI split-sleeve process, the presence of the split increases the magnitude of the compressive hoop stress adjacent to the hole. In addition, the residual hoop stresses in the transverse direction are more compressive than the residual hoop stresses in the rolling direction of rectangular specimens. This has been attributed to the geometry of the specimen as differences in material constraints in the transverse and rolling directions which influence the extents of plastic deformations and the resultant residual stress distributions. Residual stresses are also found to be nonuniform in the thickness direction. At FTI split sleeve expanded holes, the mandrel entrance side (inlet) has a lower residual compressive hoop stress.
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Scribe Marks at Fuselage Joints-Determination of Residual Stress and Effects of Fatigue Loading using Nanoindention and Synchrotron X-ray DiffractionKhan, Munhammad Kashif January 2009 (has links)
No description available.
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An evaluation of cohesive zone models for adhesive failure in bonded jointsWaqar, Sobia Iqbal January 2011 (has links)
No description available.
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Improving the Accuracy of Fracture AssessmentsMostafavi, Mahmoud January 2009 (has links)
No description available.
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Prediction and Measurement of Strains and Stresses in Metallic and Non-Metallic MaterialsNakhodchi, Soheil January 2009 (has links)
No description available.
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Strain Measurement in Solids using Ultrasonic Array Speckle ImagesBowler, Adam I. January 2010 (has links)
No description available.
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Prediction of crack propagation in natural gas transmission pipelines by means of micromechanics and strain rate dependent modelsOikonomidis, Fokon Th January 2010 (has links)
No description available.
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Acoustic emission monitoring of safe-life landing gear steel structureEl-Bakry, Murad Shawky Mohammad January 2011 (has links)
No description available.
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Residual Stresses in Shrink Fits and Quenched ComponentsHosseinzadeh, Foroogh January 2009 (has links)
No description available.
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Residual stress measurement across different length scalesHodgson, David Zhuang January 2011 (has links)
No description available.
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