Mechanical Engineering Commons^™

Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith

Master's Theses

Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. …

Synthesis Of Graphene Nanomaterials And Their Application In Electrochemical Energy Storage, Guoping Xiong

Open Access Dissertations

The need to store and use energy on diverse scales in a modern technological society necessitates the design of large and small energy systems, among which electrical energy storage systems such as batteries and capacitors have attracted much interest in the past several decades. Supercapacitors, also known as ultracapacitors, or electrochemical capacitors, with fast power delivery and long cycle life are complementing or even replacing batteries in many applications. The rapid development of miniaturized electronic devices has led to a growing need for rechargeable micro-power sources with high performance. Among different sources, electrochemical micro-capacitors or micro-supercapacitors provide higher power density …

Plasmonics Resonance Enhanced Active Photothermal Effects In Aluminum Nanoenergetics For Propulsion Applications, Jacques Abboud

Doctoral Dissertations

In this dissertation, aluminum nanoparticles (Al NPs) are shown capable to on-demand enhance and control the local photothermal energy deposition, both spatially and temporally, via active photothermal effects initiated by the localized surface plasmon resonance (LSPR) phenomenon, and amplified by the Al exothermal oxidation reactions. Experiments in dry and wet environments along with computational modeling of the photothermal process are very desirable for gaining fundamental understanding, ignition optimization and parameter exploration.

Combined phenomena of motion and ignition of Al NPs are explored first in this study. Both resulting from exposing a pile of the nanoenergetics in hand to a single …

Micro-Mechanical Assessment Of The Local Plastic Strain Invoked During A Splined Mandrel Flow Forming Operation, Meysam Haghshenas

Electronic Thesis and Dissertation Repository

Splined Mandrel Flow Forming (SMFF) is a metal spinning operation that involves the application of high multiaxial compressive stress states to invoke large plastic flow in the work piece. This allows for essentially one-step fabrication of complex internally-splined shapes. In this research project, the equivalent plastic strain, invoked throughout bcc (1020 steel) and fcc (5052 and 6061 aluminum alloys, pure copper, and 70/30 brass) samples, that were made by SMFF, was measured. The objective of the research were to measure the to obtain data on the effect of microstructure and mechanical parameters on the flow formability of ductile bcc and …

Process-Structure Relationships Of Magnesium Alloys, Arindam Banerjee

Electronic Thesis and Dissertation Repository

This research study characterizes the effects of solidification conditions on the resulting microstructure of an AM60B magnesium alloy during the solidification cycle of the casting. Seventeen control points are chosen from different sections of an instrument panel beam casting and its centerline coordinates are located. These control points locations are then used by Meridian Lightweight Technology Inc. to run a simulation in a MAGMASoft casting software to obtain temperature-time specific data.

An exact analytical solution to the Stefan problem is used to compute the one dimensional heat transfer for a section of the casting and to calculate its temperature distribution …