Other Materials Science and Engineering Commons^™

Simulation On The Sealing Of Aluminum Ball Joint, Haobin Tian, Xiaohang Liu, Xuelei Li, Jun Feng

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Antagonism Between Advanced Coatings And Lubricants?, Jun Qu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Modeling And Simulation Of Dendrite And Porosity Evolution During Solidification In The Molten Pool Of Al–Cu Alloys, Cheng Gu, Yanhong Wei, Xiaohong Zhan

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Fe Simulation For Accuracy Evolution And Control In Hot Forging Of Non-Circular Spur Bevel Gear, Wuhao Zhuang, Xinghui Han

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Mpfem Simulation On 2d Compaction Of Core–Shell Particulate Composites, Yu Liu, Fen Huang, Peng Han, Xizhong An, Haitao Fu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Atomic Structure And Energetics Of Amorphous–Crystalline Cuzr Interfaces: A Molecular Dynamics Study, X. Z. Gao, M. H. Müser, Lt Kong, J. F. Li

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Fem Investigation Of Spike Forging Test, Josef Hodek, Miroslav Urbanek, Michal Duchek

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Modelling And Simulation Of The Flexoelectric Effect On A Cantilevered Piezoelectric Nanoplate, Xining Wang

Electronic Thesis and Dissertation Repository

Piezoelectric nanomaterials have attracted increasing attentions due to their distinct electromechanical features, especially the size-dependent properties, which differ greatly from their bulk counterparts.

Due to the large strain gradients presented in nanostructures, the flexoelectricity is believed to be responsible for such size-dependent properties. In this thesis, based on the Kirchhoff plate model and the extended linear piezoelectric theory, a modified continuum mechanics based model is developed to study the size-dependent flexoelectric effect upon the static bending behaviors of a cantilevered piezoelectric nanoplate (PNP). Finite difference method (DFM) is employed to obtain the approximate numerical solutions.

The numerical results indicate that …

Nanostructured Air Electrodes And Electrochemical Reaction Mechanism Studies For Sodium-Oxygen Batteries, Hossein Yadegari

Electronic Thesis and Dissertation Repository

Alkali metal-O₂ batteries, i.e. Li- and Na-O₂, are considered as the next generation of energy saving technologies with potential application in electric transportation. The high theoretical energy density in these cells is related to the use of high energy alkali metals as negative and oxygen as the positive electrode materials. The performance of alkali metal-O₂ cells is highly dependent on the positive electrode material, where oxygen reduction and evolution reactions take place. Besides, the primary products of oxygen reduction reaction in these cells are typically metal oxides, which are insoluble in nonaqueous electrolytes, resulting in accumulation …

Acoustic Management Of Library Fishbowls, Zachary J. Lilley

Materials Engineering

The purpose of this project is to aid the Cal Poly Robert E. Kennedy library in modifying the “fishbowl” study spaces to more effectively maintain the desirable sound that is generated within the fishbowls while avoiding the entrance and exit of excess noise to and from the fishbowls. A collaboration between the Materials Engineering Department and the Architecture Department provided the combined expertise needed to design, test, and install a prototype acoustic treatment in fishbowl 216-R in consultation with the Cal Poly Library as the voice of the customer. The fishbowl’s undesirable acoustic properties can be attributed to the hard …

Reconfigurable Liquid Attenuated Collimator, Larry W. Burggraf, Benjamin R. Kowash, Jack G. M. Fitzgerald

AFIT Patents

A reconfigurable radiographic aperture mask collimator apparatus includes a body portion configured to receive an attenuating liquid having a first attenuation value per unit volume. The apparatus further includes a grid portion mated to a face of the body portion and a plurality of passageways each having a cross sectional area and a length. The plurality of passageways is disposed within the grid portion. A plurality of plugs is slidably disposed within the plurality of passageways, and each of the plurality of plugs has a second attenuation value per unit volume less than the first attenuation value. One of the …

High Strain Rate Experiments Of Energetic Material Binder, Roberto Rangel Mendoza, Michael Harr, Weinong Chen

The Summer Undergraduate Research Fellowship (SURF) Symposium

Energetic materials, in particular HMX, is widely used in many applications as polymer bonded explosives (PBX) and rocket propellant. However, when damaged, HMX is known to be an unstable substance which renders it a hazardous material and in some cases unreliable. Finding critical mechanical conditions at high rates that render various forms of energetic materials as unreliable would be vital to understand the effects that vibrations and compression forces have on energetic materials. A better understanding would enable the ability to develop improvements in the manufacturing of PBX and rocker propellant. The method utilized to evaluate the mechanical properties of …

Characterizing Hmx/Ap Cocrystal Propellant Through Planar Laser Induced Fluorescence, Seth M. Nielsen, Michael S. Powell, Steven F. Son

The Summer Undergraduate Research Fellowship (SURF) Symposium

Energetic cocrystals, or energetic materials that consist of two or more components that form a unique crystalline structure with unique properties, are currently being investigated as a possible method for decreasing the sensitivity of high energy density explosives for use in powerful solid composite propellants. Fuels more powerful than those in current use have not been practical because of their increased safety hazard due to higher sensitivity to being ignited. This has been one of the barriers that has prevented solid composite propellants from seeing significant improvements in performance. This study is an attempt to characterize a cocrystal of HMX …

Development Of Eco-Friendly Composite Foam Boards For Thermal Insulation And Packaging Purposes Using Cellulose Nanofibrils (Cnf), Nadir Yildirim

Electronic Theses and Dissertations

Reducing energy consumption is a high priority in the United States and throughout the world. Energy used to heat and cool occupied constructed facilities is of particular concern, and one of the most effective strategies is insulating the building envelope. Historically, builders used whatever material was available to fill the void between interior and exterior walls, including wool fibers, paper, and even corn cobs. Today, homes are built using foam insulation that harden when applied, blown-in loose insulation, fiberglass mats or rigid foam boards usually composed of polystyrene. Rigid foam boards are used in a variety of applications despite the …

Characterizing Local Order And Physical Properties Of Rare Earth Complex Oxides, Thomas Jacob Shamblin

Doctoral Dissertations

With more than 500 compositions, materials possessing the pyrochlore structure have a myriad of technological applications and physical phenomena. Three of the most noteworthy properties are the structure’s ability to resist amorphization making it a possible host matrix for spent nuclear fuel, its exotic magnetic properties arising from geometric frustration, and fast ionic conductivity for solid-oxide fuel cell applications. This work focuses on these three aspects of the pyrochlore’s many potential uses. Structural characterization revealed that pyrochlore-type oxides have a tendency to disorder from a high symmetry cubic structure to a lower symmetry orthorhombic arrangement in response to a variety …

Lignin-Based Li-Ion Anode Materials Synthesized From Low-Cost Renewable Resources, Nicholas William Mcnutt

Doctoral Dissertations

In today’s world, the demand for novel methods of energy storage is increasing rapidly, particularly with the rise of portable electronic devices, electric vehicles, and the personal consumption and storage of solar energy. While other technologies have arguably improved at a rate that is exponential in accordance with Moore’s law, battery technology has lagged behind largely due to the difficulty in devising new electric storage systems that are simultaneously high performing, inexpensive, and safe.

In order to tackle these challenges, novel Li-ion battery anodes have been developed at Oak Ridge National Laboratory that are made from lignin, a low-cost, renewable …

Thermoelectric Half-Heuslers: Synthesis, Processing, And Performance, Joseph Robert Croteau

Boise State University Theses and Dissertations

Thermoelectric half-Heusler compounds have potential to convert the heat wasted from industrial and transportation processes to useful electricity. Among the highest performing half-Heusler compounds are nano-structured bulk materials which have been arc-melted, pulverized into a nano-powder, and sintered by DC-hot press. High performing n- and p-type half-Heusler compounds with nominal composition of Hf_0.25Zr_0.75NiSn_0.99Sb_0.01 and Nb_0.75Ti_0.25FeSb, respectively, have been provided to us in both dense and powder form by our collaborators at the University of Houston. We consolidate these powders by SPS, refine these powders to improve both particle size …

Silicon Anode Materials For Next Generation Lithium-Ion Batteries, Qizheng Li

Electronic Thesis and Dissertation Repository

Lithium Ion Batteries (LIBs) are a promising green energy storage system with application toward portable electronic devices, electronic vehicles (EVs) and smart grid energy storage. High energy density is one of the most important advantages for LIB, however, improvements toward performance measures, such as energy density, power and rate capability, cycling life, safety and cost, need to meet the different requirements for various applications. It is well known that battery performance is highly dependent on the type of electrode material that is employed. Currently most LIBs are predominantly fabricated using graphite as an anode material. Therefore, finding a qualified candidate …

Application Of Molecular Layer Deposition For Graphite Anodes In Lithium-Ion Batteries And Porous Thin-Film Materials, Craig L. Langford

Electronic Thesis and Dissertation Repository

With climate change occurring because of greenhouse gas emissions, the demand for emission free transportation has led to the development of electric vehicles. Improving the batteries’ cycling stability, capacity and safety have been the leading challenges to compete with gasoline and diesel engines. With advances in thin-film deposition techniques via atomic and molecular layer deposition, ultrathin films can be deposited to control the surface chemistry of the battery’s active materials. This thesis aims to understand two main aspects of molecular layer deposition. First, how it can influence solid electrolyte interface formation on the graphite surface during cycling in a lithium-ion …

Enzyme Stabilization In Hierarchical Biocatalytic Food Packaging And Processing Materials, Dana Erin Wong

Doctoral Dissertations

The partnership of biocatalysts and solid support materials provides many opportunities for bioactive packaging and bioprocessing aids beneficial to the agricultural and food industries. Biocatalysis, or reactions modulated by enzymes, allows bioactive materials to assist in bringing a substrate to product. Enzymes are proteins which catalyze reactions by lowering the activation energy required to drive the production of a desired product. Enzymes are commonly utilized in food processing as catalysts with specificity in order to enhance product quality through the production of beneficial food components, and to break down undesirable components that may be harmful or may decrease product quality. …

Novel In Situ Study Of Magnetocaloric Heusler Alloy, Roozbeh Nikkhah Moshaie

FIU Electronic Theses and Dissertations

The objective of this research was to develop a novel technique for mechanical treatment to manipulate the microstructure of Nickel-Manganese-Gallium Hesuler alloys to increase anisotropy, which can lead to higher magnetocaloric properties. Ni_2+xMn_1-xGa intermetallics have the potential to be employed in magnetic refrigeration devices including residential refrigerators, heat pumps, and air conditioning. Solid-state magnetic refrigeration systems are smaller, quieter, and reduce energy consumption by 20% compared to existing conventional vapor-cycle refrigeration devices which rely on harmful hydro-fluorocarbon gases and pump millions of tons of greenhouse gases into the atmosphere. The magnetic refrigeration market is predicted to …

Carbon Nanoadditives To Enhance Latent Energy Storage Of Phase Change Materials, Shadab Shaikh, Khalid Lafdi, Kevin P. Hallinan

Kevin Hallinan

Latent energy storage capacity was analyzed for a system consisting of carbon nanoparticlesdopedphase changematerials (PCMs). Three types of samples were prepared by doping shell wax with single wall carbon nanotubes(SWCNTs), multiwall CNTs, and carbon nanofibers. Differential scanning calorimetry was used to measure the latent heat of fusion. The measured values of latent heat for all the samples showed a good enhancement over the latent heat of pure wax. A maximum enhancement of approximately 13% was observed for the wax/SWCNT composite corresponding to 1% loading of SWCNT. The change in latent heat was modeled by using an approximation for the intermolecular …

Carbon Fiber As Anode Material For Cathodic Prevention In Cementitious Materials, Emma Qingnan Zhang, Luping Tang, Thomas Zack

International Conference on Durability of Concrete Structures

Cathodic prevention (CPre) technique is a promising method and has been used for the past two decades to prevent steel from corrosion in concrete structures. However, wide application of this technique has been restricted due to high costs of anode materials. In order to lower the cost and further improve this technique, carbon fiber composite anode has been introduced as an alternative anode material with affordable price and other outstanding properties. This paper presents the study of using carbon fiber mesh as anode material for long-term cathodic prevention system and the effect of accelerated current on macro- and microstructure of …

Comparison Study Of Tensile Strength , Ductility, And Fracture Mode Of H11, Arp 2000, And Mp35n Connecting Rod Bolts For Use In High Performance Racing Engines, Megan Mccabe, Samuel Randall

Materials Engineering

Oliver Racing Parts (ORP) has historically purchased connecting rod bolts made of high strength, high cost, nickel-cobalt alloy, MP35N, and a medium strength, low cost, proprietary tool steel called ARP 2000. ORP has recently acquired capabilities to manufacture their own bolts. To determine the quality of their product as it compares to their previous supplier, ORP produced three different types of ⅜” diameter bolts: one set of bolts made of MP35N, and two sets of H11 bolts, designated H11A and H11B for their respective processing. The H11, ARP 2000, and MP35N bolts were tensile tested using a custom designed test …

Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength, Nicholas Bruffey, William Shiu

Materials Engineering

The design process at Zodiac Aerospace requires the ability to accurately predict the strength of a composite honeycomb core sandwich panel to adhere to strict FAA regulations. The most common failure mode in long beam composites is in compression. Following ASTM D7249 for a four-point bend test of a long beam flexural test, a mechanical model has been developed that relates the compressive strength of glass fiber face sheets to the flexural strength of the sandwich panel. Zodiac does not currently have data on the compressive strength of the face sheets, so testing was performed to find this property. Asymmetric …

Reducing Food And Packaging Waste Through Developing Edible Fruit Based Packaging Prototypes, Melanie Thatcher

Materials Engineering

Packaging is used to contain, preserve, protect, and advertise both manufactured and natural products. In 2013 it was reported that over thirty percent of solid waste in the United States was from packaging. One way to reduce the impact of packaging on the environment is to create a solution that is edible and sourced from a waste or secondary food product that is not currently being utilized. Food-contact packaging made from recycled materials must meet strict U.S. Food and Drug Administration (FDA) regulations to be utilized as raw material for packaging. Fruit pomace is a candidate material since it may …

Life Cycle Assessment And Comparison Of Magnesium Oxide Nanoparticles Prepared By Aqueous And Microwave Synthesis Methods, Jesse Cartland

Materials Engineering

Abstract: Magnesium oxide nanoparticles are being used increasingly as catalysts for organic synthesis, fuel oil additives, and CO₂ adsorbents. There are many ways to produce magnesium oxide nanoparticles, but there is little information available regarding the environmental costs of production. As demand for environmentally friendly materials increases, it is important to understand environmental impact differences between various production methods. This study will compare the differences in embodied energy and global warming potential (GWP) between two synthesis methods: microwave combustion synthesis (microwave synthesis) and oxidation of magnesium hydroxide (aqueous synthesis). The resulting nanoparticles were characterized using scanning electron microscopy (SEM), …

Investigation Of Outlife Time On The Environmental Durability Of P2-Etched, Adhesively-Bonded Aluminum Alloys Using The Astm Wedge Test, Daniel Gross, Corey Sutton

Materials Engineering

P2 etchant is an environmentally-friendly aluminum etchant which has the potential to replace the Forest Products Laboratory (FPL) etchant as the industry standard. Environmental durability of adhesively-bonded aluminum surfaces etched using a paste version of the P2 etchant were tested using the Boeing-developed wedge test (ASTM D3762 - 03(2010)). This project specifically aimed to examine the relationship between outlife time (the time between etching and adhering) and the ability of bonded aluminum samples to pass the wedge test. Two aluminum alloys, 2024-T3 and 7075-T6, were wedge tested and the etched surfaces examined with an atomic force microscope (AFM) and a …

Selection Of A Flexible Polymer To Protect Dry Carbon Fibers In A Cfrp Wallet Hinge, Evan Dowey, Matthew Johnson

Materials Engineering

Common Fibers, a company founded by Cal Poly alumni, produces carbon fiber wallets. The invention of their built-in fiber-matrix composite hinge reduces the need for extra complexity and added mass that is inherent with using standard metal hinges to join standard composite panels. Replacing the polyurethane tape on the wallet hinge allows for improved protection while maintaining flexibility and other performance properties is critical to the success of such a design. The most important material property in this project is the bond strength between carbon fiber and a variety of flexible resin candidates. The silicone and urethane based elastomer resins …

Improving Surface Roughness Of Optically Telegraphed Composite Laminations, Michael Smith

Materials Engineering

In collaboration with Watson Furniture, this project seeks to identify the cause of surface roughness on composite panels processed into commercial furnishings. The surface roughness was examined and measured using an optical microscope, a scanning electron microscope (SEM), and a profilometer. The SEM and optical microscope provided qualitative data on the surface roughness as well as the film build of each layer. After an initial characterization of the manufactured samples provided by Watson Furniture, additional samples were fabricated for testing using different manufacturing processes than those used by Watson Furniture. These samples were constructed in-house using raw materials provided by …