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The Sedimentary Record Of Eocene Deformation In The Interior Of The Southern Canadian Cordillera, Erica May Rubino

Theses and Dissertations

Eocene sedimentary strata exposed in the interior of the southern Canadian Cordillera (SCC) in British Columbia (BC) and northernmost Washington (WA) record a poorly understood history of extension-related deformation in the hinterland of the orogen. Today these strata are exposed in isolated, distinct outcrop belts, although the nature of the original basin(s) is unknown. We examined 650 m of Eocene strata, analyzed 2,995 detrital zircons for uranium-lead (U-Pb) ages, and measured 67 detrital zircons for Hf isotope systematics in an effort to better understand the physiography of the SCC during this time period. Eocene strata consist of clast- and matrix-supported …

Multiscale Deformation And Failure Behavior Of Polymer Bonded Explosives Subjected To High Rate Loading, Suraj Muthiramalil Ravindran

Theses and Dissertations

Polymer bonded explosives (PBX) are heterogeneous granular composites with a high-volume fraction of solid. Typically, they contain 80-95% explosive crystals and 5- 20% soft polymer binder. These materials are subjected to different loading conditions during their service life. The main function of the soft binder is to reduce shock sensitivity to prevent an accidental explosion. However, there have been inadvertent detonations in these materials during transportation and handling. The reason for such unintentional explosion is not well understood. It is commonly accepted that the formation of local hightemperature regions, called ‘hot spots’, is the primary cause. Hotspot formation is associated …

The Mechanical Properties And Deformation Behavior Of Heat Treated Versus As-Received Inconel X-750, Christopher Marsh

Theses and Dissertations

X-750 is a nickel-chromium based super alloy of usefulness in a wide variety of applications such as gas turbines, rocket engines, nuclear reactors, pressure vessels, tooling, and aircraft structures. Its good mechanical properties are due to the strengthening from precipitation of γ′ particles upon prior ageing heat treatment. In this work, the effect of such heat treatment on the mechanical properties, tensile behavior, and fracture mechanisms of X-750 was studied at various temperatures by comparing it with a non-aged, solution annealed X-750. Tensile tests were conducted from room temperatures up to 900 °C at three separate strain rates (10-3, 10-4, …

Deformation Of Multifunctional Materials At Various Time And Length Scales: A Dic-Based Study, Behrad Koohbor

Theses and Dissertations

The focus in the present work is to explore and characterize the underlying deformation and failure mechanisms in multifunctional materials including woven composites and polymeric foams, using full-field measurements. Attention has been especially drawn towards the challenges associated with characterizing these materials at extreme length and time scales, and investigating the advantages of full-field measurements to resolve the existing limitations. Accordingly, the current limitations in the study of dynamic deformation response of low-impedance materials are identified. An approach based on the general stress equilibrium is presented and successfully implemented to include the concurrent effects of inertia and material compressibility into …

Deformation Induced Martensitic Transformation In 304 Stainless Steels, Junliang Liu

Theses and Dissertations

304 stainless steel is an austenitic steel widely used for various applications due to a good combination of strength and ductility and relative low cost. It is known to be metastable as the austenite phase can transform into martensite under stress. In this work, a new method (in-situ tensile TEM) and the traditional method (ex-situ tensile tests and TEM, XRD characterization) were used to investigate the mechanisms of deformation-induced martensitic transformation in 304SS samples at different temperatures.

The ex-situ tensile tests were conducted under a strain rate of 10-3 s-1 until rupture. After the tensile tests, the fractured area was …