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A Non-Contact Measurement Technique At The Micro ScaleGhosh, Santaneel January 2005 (has links)
During their production and normal use, electronic packages experience large temperature excursions, leading to high thermo-mechanical stress gradients that cause fatigue failure of the solder joints. In order to prevent premature failure and prolong the fatigue life of solder joints, there is a pressing need for the characterization of the solder, especially lead-free solder, at the micro-level (joint size). The characterization and modeling of solder behavior at the appropriate scale is a major issue. However, direct measurement techniques are not applicable to characterize the deformation response of solder joints because of their micro scale dimensions. Therefore, a non-contact measurement technique utilizing a Scanning Electron Microscope (SEM) in conjunction with Digital Image Correlation (DIC) has been developed. Validation was achieved by performing a four-point bending test in both an in-house optical system with DIC and inside the SEM. This non-contact measurement technique was then used to extract the stress-strain response of the solder. Mechanical tests were performed on solder joints that were created using the same type of solder balls used in the electronic industry and were representative of normal joint scales. The SEM-DIC technique has been proven to be applicable for the determining the stress-strain response of solder material at the micro-scale.This study resulted in a validated material characterization technique specifically designed for micro-scale material response. One of the main contributions of this study is that the method is a lot simpler and cheaper, yet highly effective, compared to the previous methods. This technique is also readily applicable to the measurement of the stress-strain response of any micro-scale specimen, such as other metals, polymers, etc. Also, the measured displacement field by obtained by DIC can be used as the base for calculating the strain field on the surface of a specimen.
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The role of energy restriction and environmental agent exposure in the aetiology of malnutrition related diabetes mellitus (MRDM)McDonagh, Margaret P. January 1997 (has links)
No description available.
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Oxidative stress and biomolecule damage in human IDDMHannon-Fletcher, Mary Philomena Anne January 1999 (has links)
No description available.
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The photodecomposition of carboxylate complexes of ionic iron (III) porphyrins in solutionOsborne, Victoria A. January 1999 (has links)
No description available.
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An investigation of nitroxide-mediated polymerisationFraser, Kathryn January 1998 (has links)
No description available.
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The application of magnetic resonance techniques to studies of the action of vitamin E, free radicals and calcium in tissue damageJohnson, K. M. January 1988 (has links)
No description available.
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Reactive oxygen species in atherosclerosisSmith, Cheryl January 1993 (has links)
No description available.
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Simulation studies of the structure and energetics of a host-guest systemHenchman, Richard Humfry January 1999 (has links)
No description available.
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Plasma diagnostics of free radical speciesHarkin, C. G. January 1987 (has links)
No description available.
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The superoxide production and NADPH oxidase of articular chondrocytesHiran, Tejindervir Singh January 1998 (has links)
No description available.
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