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Mechanical Engineering

2017

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Full-Text Articles in Materials Science and Engineering

Investigation Of 2195 And 2219 Post Weld Heat Treatments For Additive Friction Stir Lap Welds, Matthew Champagne Dec 2017

Investigation Of 2195 And 2219 Post Weld Heat Treatments For Additive Friction Stir Lap Welds, Matthew Champagne

University of New Orleans Theses and Dissertations

To evaluate potential uses for friction stir welding in additive manufacturing, two separate parts were fabricated, one of 2195-T84 and the other 2219-T87, utilizing fixed pin techniques and additive lap welds. The parts were cut into samples, artificially aged and subjected to Rockwell hardness (HRB), Vickers hardness, micrographic photography, and metallographic imaging on both pre- and post- heat treatment. Additionally, tensile testing was performed on the heat-treated samples. A comparisons of test results showed a minimal increase in the yield strength of the 2195-T84 samples compared to as-welded tensile results obtained from a previous project. The ultimate tensile strength was …


Design, Manufacture, And Structural Dynamic Analysis Of A Biomimetic Insect-Sized Wing For Micro Air Vehicles, Jose Enrique Rubio Dec 2017

Design, Manufacture, And Structural Dynamic Analysis Of A Biomimetic Insect-Sized Wing For Micro Air Vehicles, Jose Enrique Rubio

University of New Orleans Theses and Dissertations

The exceptional flying characteristics of airborne insects motivates the design of biomimetic wing structures that can exhibit a similar structural dynamic behavior. For this purpose, this investigation describes a method for both manufacturing a biomimetic insect-sized wing using the photolithography technique and analyzing its structural dynamic response. The geometry of a crane fly forewing (family Tipulidae) is acquired using a micro-computed tomography scanner. A computer-aided design model is generated from the measurements of the reconstructed scanned model of the insect wing to design the photomasks of the membrane and the venation network required for the photolithography procedure. A composite …


The Inter-Laminar Shearing Effect On Wrinkle Development In Composite Forming Processes, David Sundquist Dec 2017

The Inter-Laminar Shearing Effect On Wrinkle Development In Composite Forming Processes, David Sundquist

McKelvey School of Engineering Theses & Dissertations

Composite materials are becoming prevalent in aerospace industries as the uniqueness of the composite structure allows the composite to be tailored specifically for individual applications. Many fabrication techniques produce defects in composite parts such as wrinkles, fiber waviness, fiber misalignment, and porosity. The driving mechanisms behind these defects occurring during forming processes are not fully understood and, thus, characterization formation of these defects in a uncured state is beneficial to optimize composite processing. This work primarily investigated the influence of how uncured pre-impregnated carbon ply properties affect the wrinkling behavior of a composite laminates. Several factors affecting composite ply forming …


Heterogeneous Anisotropy Index And Scaling In Multiphase Random Polycrystals, Muhammad Ridwan Murshed Dec 2017

Heterogeneous Anisotropy Index And Scaling In Multiphase Random Polycrystals, Muhammad Ridwan Murshed

Theses and Dissertations

Under consideration is the finite-size scaling of elastic properties in single and two-phase random polycrystals with individual grains belonging to any crystal class (from cubic to triclinic). These polycrystals are generated by Voronoi tessellations with varying grain sizes and volume fractions. By employing variational principles in elasticity, we introduce the notion of a 'Heterogeneous Anisotropy Index' and investigate its role in the scaling of elastic properties at finite mesoscales. The index turns out to be a function of 43 variables, 21 independent components for each phase and the volume fraction of either phase. Furthermore, the relationship between Heterogeneous Anisotropy Index …


Innovation Of Hydrocarbon Investigation Using Audio-Magnetotelluric In Cepu Field, Indonesia, Iqbal Fauzi Aditama, Widodo Widodo Dec 2017

Innovation Of Hydrocarbon Investigation Using Audio-Magnetotelluric In Cepu Field, Indonesia, Iqbal Fauzi Aditama, Widodo Widodo

Makara Journal of Technology

An audio-magnetotelluric (AMT) survey has been performed at Cepu oil field located in Indonesia. The objective of this research is to detect resistivity structures of this important hydrocarbon rock. This research can be classified as an innovation in application of the AMT method for hydrocarbon exploration. The lack of seismic resolution has been provided by the AMT method, especially in the location of sub-basalt and sub-salt plays. In additional, the cost of AMT survey is quite low compared to seismic. The forward modelling is included in this research to understand the measurement data response from a mathematical model. In the …


Adsorption Of Cu(Ii) Ions In Aqueous Solution Onto Limonia Acidissima Shellbased Activated Carbon: Kinetic And Isotherm Studies, Abrar Muslim, Syahiddin Dahlan Said, Gita Suci Hariati, Siti Fajar Karina, Fauzi Muhammad Djuned, Rizka Mulyawan Dec 2017

Adsorption Of Cu(Ii) Ions In Aqueous Solution Onto Limonia Acidissima Shellbased Activated Carbon: Kinetic And Isotherm Studies, Abrar Muslim, Syahiddin Dahlan Said, Gita Suci Hariati, Siti Fajar Karina, Fauzi Muhammad Djuned, Rizka Mulyawan

Makara Journal of Technology

Adsorption of Cu(II) ions from aqueous solution using activated carbon prepared from Limonia acidissima fruit shell (LAFS-AC) was conducted in batch mode experiments at pH 5 (±0.15), 100 rpm and 1 atm. The effects of contact time, initial Cu(II) ions concentration, KOH concentration, and adsorption temperature on Cu(II) ions adsorption capacity were investigated. Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy analyses were performed to investigate the active site and surface morphology of the LAFS-AC, respectively. The Cu(II) ions adsorption was fitted very well (R2 = 0.94 on average) to the pseudo second-order adsorption kinetic with the adsorption capacity and …


Experimental Study Of The Chimney Height Variation Against Double Pots Biomass Stove Performance, Faisal Faisal, Adi Setiawan, Wusnah Wusnah, Khairil Khairil, Luthfi Luthfi, Mona Fajriana Dec 2017

Experimental Study Of The Chimney Height Variation Against Double Pots Biomass Stove Performance, Faisal Faisal, Adi Setiawan, Wusnah Wusnah, Khairil Khairil, Luthfi Luthfi, Mona Fajriana

Makara Journal of Technology

This research aims to get optimal chimneys height of double pots biomass stove. Optimal chimneys height needs to provide best performance of the stove. Experimental study was done by varied the chimney heights. Water boiling test as the standard method was used to obtained stove performance for each chimney height variation. The results showed that best performance stove was the one with 1.65 cm chimney height, with thermal efficiency at 37.66%.


Indonesia’S Municipal Solid Waste 3r And Waste To Energy Programs, Farizal Farizal, Radityo Aji, Amar Rachman, Nasruddin Nasruddin, Teuku Meurah Indra Mahlia Dec 2017

Indonesia’S Municipal Solid Waste 3r And Waste To Energy Programs, Farizal Farizal, Radityo Aji, Amar Rachman, Nasruddin Nasruddin, Teuku Meurah Indra Mahlia

Makara Journal of Technology

Like most cities in the world, population in Indonesia continues to grow every year. Problems that can arise from this are the increasing amount of municipal solid waste (MSW) production and the growing demand for electricity. To deal with the problems, Indonesian government runs 3R (Reduce, Reuse and Recycle) and WTE (Waste to Energy) Programs simultaneously. 3R program aims to reduce the number of waste, while WTE program aims to generate electricity as an alternative energy source. This study aims to find out the optimal proportion of MSW treated through the 3R and WTE programs. For the purpose, a goal …


Energy Potentials Of Briquette Produced From Tannery Solid Waste, Olatunde Ajani Oyelaran, Faralu Muhammed Sani, Olawale Monsur Sanusi, Olusegun Balogun, Adeyinka Okeowo Fagbemigun Dec 2017

Energy Potentials Of Briquette Produced From Tannery Solid Waste, Olatunde Ajani Oyelaran, Faralu Muhammed Sani, Olawale Monsur Sanusi, Olusegun Balogun, Adeyinka Okeowo Fagbemigun

Makara Journal of Technology

The vast quantity of waste generated from industries is one of the serious outcomes of unplanned development, resulting into quantum of hazardous organic and inorganic waste generating daily. Proper waste management is a challenging issue that must be addressed adequately. This is, therefore, carried out with a view of assessing the energy and combustion quality of tannery solid waste with a view of converting them into briquettes for cooking, heating and small home industries and reducing the menace caused by tannery waste disposal. The results of the experiments showed that the combustion rate ranged between 0.171 and 0.217 g/min, the …


Study On Semiconductor Properties Of Acetylide-Thiourea Fabricated Onto Interdigitated Electrodes (Ides) Platform Towards Application In Gas Sensing Technology, Adibah Izzati Daud, Wan M. Khairul, M. I. N. Isa, Khairul Anuar Abdul Wahid Dec 2017

Study On Semiconductor Properties Of Acetylide-Thiourea Fabricated Onto Interdigitated Electrodes (Ides) Platform Towards Application In Gas Sensing Technology, Adibah Izzati Daud, Wan M. Khairul, M. I. N. Isa, Khairul Anuar Abdul Wahid

Makara Journal of Technology

In the past few decades, the unique properties of acetylide and thiourea moieties individually have attracted great attention from researchers in various fields to be developed in numerous applications in advanced materials technology, especially as an active layer in gas sensing devices. The molecular systems of acetylide and thiourea provide a wide range of electronic properties as they possess rigid π-systems in their designated structures. In this study, a derivative of acetylide-thiourea featuring N-(4[4-aminophenyl] ethynyl benzonitrile)-N’-(4-ethyl benzoyl) thiourea (TCN) has been synthesised with the general formula of ArC(O)NHC(S)NHC≡C)Ar adopted the system of D-π-A for the significant development of conductive materials. …


Assessment On Heck-Immine Derivatives As Organic Semiconductor Materials, Rafizah Rahamathullah, Lim Keemi, Wan M. Khairul Dec 2017

Assessment On Heck-Immine Derivatives As Organic Semiconductor Materials, Rafizah Rahamathullah, Lim Keemi, Wan M. Khairul

Makara Journal of Technology

This paper reports the synthetic, characterization and theoretical evaluation of new class of hybrid Heck-immine system involving mixed moieties of vinylene (C=C) and azomethines (CH=N) which has been successfully integrated into an addition of organic semiconducting materials. The assessment of 4-[(hexyloxyphenyl)methylene]amino)-4’-chloro-stilbene (HEXCS) based on Donor (D)-π-Acceptor (A) was evaluated as active semiconductor material candidates via several spectroscopic and analytical techniques. In turn, the investigation of its potential as dopant system in conductive film was successfully deposited on indium tin oxide (ITO) coated substrate via spin coating method. The relationship between electronic and optical properties, chemical modelling at molecular interactions and …


Experimental Study On Automatic Control For Collision Avoidance Of Ships, Daeng Paroka, Muhammad Fahmi Kamil, Andi Haris Muhammad Dec 2017

Experimental Study On Automatic Control For Collision Avoidance Of Ships, Daeng Paroka, Muhammad Fahmi Kamil, Andi Haris Muhammad

Makara Journal of Technology

Automatic control system is widely applied to control the ship direction or heading angle in accordance with the decided trajectory. Several methods for improving performance of control system have been developed such as Proportional-Integral-Derivative (PID) control and fuzzy logic based control. Within the last decade, application of automatic control system is not only for ship navigation but also for avoiding collision risk of ships in seaways. This paper discusses the application of automatic control system for avoiding ship collision by free running experiment. Fuzzy logic based control was developed using Mamdani Centroid method to estimate the necessary rudder angle in …


Material Properties Design Using Simulations And Experiments For Powder Injection Molding Of Lead Zirconate Titanate (Pzt)., Bhushan Pramod Bandiwadekar Dec 2017

Material Properties Design Using Simulations And Experiments For Powder Injection Molding Of Lead Zirconate Titanate (Pzt)., Bhushan Pramod Bandiwadekar

Electronic Theses and Dissertations

Powder injection molding (PIM) process simulations can be performed to minimize the number of injection molding experiments by estimating material properties necessary for PIM simulations. In current work, lead zirconate titanate (PZT) powder-polymer binder feedstock was compounded for 45 vol. % and 52 vol. % solids loading. PIM experiments on designed micro-pillar array geometry were performed using 52 vol. % PZT. Using PIM experiments results as basis, PIM simulations were performed on designed micro-pillar array geometries to understand the effectiveness of PIM simulations with the use of estimated feedstock properties in predicting molding behavior that have micro-features. Additionally, PIM simulations …


Investigation On Ti6al4v-V-Cr-Fe-Ss316 Multi-Layers Metallic Structure Fabricated By Laser 3d Printing, Wei Li, Frank W. Liou, Joseph William Newkirk, Karen M. Brown Taminger, William J. Seufzer Dec 2017

Investigation On Ti6al4v-V-Cr-Fe-Ss316 Multi-Layers Metallic Structure Fabricated By Laser 3d Printing, Wei Li, Frank W. Liou, Joseph William Newkirk, Karen M. Brown Taminger, William J. Seufzer

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Joining titanium alloy and stainless steel is becoming an urgent need since their outstanding mechanical properties can be utilized integratedly. However, direct fusion joining of Ti6Al4V to SS316 can cause brittle Ti-Fe intermetallics which compromise join bonds’ mechanical properties. In this research, Laser 3D Printing was applied to explore a new Ti6Al4V to SS316 multi-metallic structure. A novel filler transition route was introduced (Ti6Al4V → V → Cr → Fe → SS316) to avoid the Ti-Fe intermetallics. Two experimental cases were performed for comparison to evaluate this novel route’s effect. In the first case, SS316 layer was directly deposited on …


Design, Analysis, And Application Of A Cellular Material/Structure Model For Metal Based Additive Manufacturing Process., Shanshan Zhang Dec 2017

Design, Analysis, And Application Of A Cellular Material/Structure Model For Metal Based Additive Manufacturing Process., Shanshan Zhang

Electronic Theses and Dissertations

Powder bed fusion additive manufacturing (PBF-AM) has been broadly utilized to fabricate lightweight cellular structures, which have promising potentials in many engineering applications such as biomedical prosthesis, aerospace, and architectural structures due to their high performance-to-weight ratios and unique property tailorabilities. To date, there is still a lack of adequate understanding of how the cellular materials are influenced by both the geometry designs and process parameters, which significantly hinders the effective design of cellular structures fabricated by PBF-AM for critical applications. This study aims to demonstrate a cellular structure design methodology that integrates geometrical design and process-material property designs. Utilizing …


Usa Boccia Ball Ramp For Athletes With Quadriplegia, Alissa A. Koukourikos, Matthew Lee, Nathan Bernards Dec 2017

Usa Boccia Ball Ramp For Athletes With Quadriplegia, Alissa A. Koukourikos, Matthew Lee, Nathan Bernards

Mechanical Engineering

In this report, the design process in creating an assistive device for Boccia Classification 3 (BC3) players is outlined. The initial research steps, including research into the rules of the game, capabilities of the players, and existing products is documented to show where ideas for the product stemmed from. This transitions into requirements that the sponsor requested, and preliminary designs and ideas for the product. Finally, this report explains the details of the final design, which has been analyzed for safety, ease of use, and ability to function under different conditions. The processes of manufacturing and testing will also be …


Evolution Of The Pore Size Distribution In Sheared Binary Glasses, Nikolai V. Priezjev, Maxim A. Makeev Nov 2017

Evolution Of The Pore Size Distribution In Sheared Binary Glasses, Nikolai V. Priezjev, Maxim A. Makeev

Mechanical and Materials Engineering Faculty Publications

Molecular dynamics simulations are carried out to investigate mechanical properties and porous structure of binary glasses subjected to steady shear. The model vitreous systems were prepared via thermal quench at constant volume to a temperature well below the glass transition. The quiescent samples are characterized by a relatively narrow pore size distribution whose mean size is larger at lower glass densities. We find that in the linear regime of deformation, the shear modulus is a strong function of porosity, and the individual pores become slightly stretched while their structural topology remains unaffected. By contrast, with further increasing strain, the shear …


Investigating Scalable Manufacturing Of High-Conductivity Wires And Coatings From Ultra-Long Carbon Nanotubes, Pouria Khanbolouki Nov 2017

Investigating Scalable Manufacturing Of High-Conductivity Wires And Coatings From Ultra-Long Carbon Nanotubes, Pouria Khanbolouki

Mechanical Engineering ETDs

Carbon nanotubes (CNTs) are a promising candidate for next generation of electrical wirings and electromagnetic interference (EMI) shielding materials due to their exceptional mechanical and electrical properties. Wires and coatings from ultralong nanotubes that are highly crystalline, well-aligned and densely packed can achieve this goal. High-performance CNT conductors will be relatively lightweight and resistant to harsh conditions and therefore can potentially replace current conductors in many industries including aerospace, automotive, gas and oil.

This thesis investigates a new manufacturing approach, based on conventional solution coating and wire drawing methods, to fabricate high conductivity wires and coatings from ultra-long carbon nanotubes. …


Effect Of Ultrasonic Treatment On The Microstructure And Mechanical Properties Of Al6061 And Composite, Ana S. Exime Nov 2017

Effect Of Ultrasonic Treatment On The Microstructure And Mechanical Properties Of Al6061 And Composite, Ana S. Exime

FIU Electronic Theses and Dissertations

In this study, the effect of ultrasonic treatment (UST) parameters such as amplitude, sonication time, and melt temperature on microstructure and microhardness of Al 6061 alloy is evaluated. The effect of UST on the dispersion of tungsten disulfide (WS2) and carbon nanotubes (CNT) as reinforcement particles in Al 6061 during casting is also studied. The cast Al 6061 with UST demonstrated 32% grain size reduction and 8% increase in the microhardness for optimum processing conditions. The cavitation process induced by UST is responsible for the refinement in microstructure and increase of hardness by enhancing the degassing and nucleation …


Friction Stir Welding Manufacturing Advancement By On-Line High Temperature Phased Array Ultrasonic Testing And Correlation Of Process Parameters To Joint Quality, Daniel James Huggett Nov 2017

Friction Stir Welding Manufacturing Advancement By On-Line High Temperature Phased Array Ultrasonic Testing And Correlation Of Process Parameters To Joint Quality, Daniel James Huggett

LSU Doctoral Dissertations

Welding, a manufacturing process for joining, is widely employed in aerospace, aeronautical, maritime, nuclear, and automotive industries. Optimizing these techniques are paramount to continue the development of technologically advanced structures and vehicles. In this work, the manufacturing technique of friction stir welding (FSW) with aluminum alloy (AA) 2219-T87 is investigated to improve understanding of the process and advance manufacturing efficiency. AAs are widely employed in aerospace applications due to their notable strength and ductility. The extension of good strength and ductility to cryogenic temperatures make AAs suitable for rocket oxidizer and fuel tankage. AA-2219, a descendent of the original duralumin …


The Rheology And Roll-To-Roll Processing Of Shear-Thickening Particle Dispersions, Sunilkumar Khandavalli Nov 2017

The Rheology And Roll-To-Roll Processing Of Shear-Thickening Particle Dispersions, Sunilkumar Khandavalli

Doctoral Dissertations

Particle dispersions are ubiquitous in our daily lives ranging from food and pharmaceutical products to inks. There has been great interest in the recent years in formulation of functional inks to fabricate myriad flexible electronic devices through high-throughput roll-to-roll technologies. The formulations often contain several functional additives or rheological modifiers that can affect the microstructure, rheology and processing. Understanding the rheology of formulations is important for tuning the formulation for optimal processing. This thesis presents investigations on the rheology of particle dispersions and their impact on roll-to-roll technologies. Shear-thickening behavior is common in particle dispersions, particularly, concentrated particulate inks. We …


Numerical Simulation Of Multi-Phase Core-Shell Molten Metal Drop Oscillations, Kaushal Sumaria Oct 2017

Numerical Simulation Of Multi-Phase Core-Shell Molten Metal Drop Oscillations, Kaushal Sumaria

Masters Theses

The surface tension of liquid metals is an important and scientifically interesting parameter which affects many metallurgical processes such as casting, welding and melt spinning. Conventional methods for measuring surface tension are difficult to use for molten metals above temperatures of 1000 K. Containerless methods are can be used to measure the surface tension of molten metals above 1000 K. Oscillating drop method is one such method where a levitated droplet is allowed to undergo damped oscillations. Using the Rayleigh’s theory for the oscillation of force-free inviscid spherical droplets, surface tension and viscosity of the sample can be calculated from …


Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic Oct 2017

Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic

Mechanical Engineering Faculty Publications

We review the process rates and energy intensities of various additive processing technologies and focus on recent progress in improving these metrics for laser powder bed fusion processing of metals, and filament and pellet extrusion processing of polymers and composites. Over the last decade, observed progress in raw build rates has been quite substantial, with laser metal processes improving by about 1 order of magnitude, and polymer extrusion processes by more than 2 orders of magnitude. We develop simple heat transfer models that explain these improvements, point to other possible strategies for improvement, and highlight rate limits. We observe a …


Orientation Dependent Compression Behavior Of Co35Ni35Al30 Single Crystals, Peizhen Li, Haluk E. Karaca, Yury I. Chumlyakov Sep 2017

Orientation Dependent Compression Behavior Of Co35Ni35Al30 Single Crystals, Peizhen Li, Haluk E. Karaca, Yury I. Chumlyakov

Mechanical Engineering Faculty Publications

The shape memory effect (SME) and superelasticity (SE) behavior of homogenized Co35Ni35Al30 single crystals were systematically characterized along the [100], [110] and [111] orientations under compression. The shape memory behavior of CoNiAl was found to be highly orientation and stress/temperature dependent. Maximum compressive recoverable strains were 3.98 % in [110], 3 % in [100] and 0.30 % in [111] orientations, respectively. The Co35Ni35Al30 demonstrated a very high superelastic temperature window of more than 350 °C along the [100] and [110] orientations. Moreover, two-way shape memory effect with very low thermal …


3d Printing Of Functional Materials: Surface Technology And Structural Optimization, Dongxing Zhang Sep 2017

3d Printing Of Functional Materials: Surface Technology And Structural Optimization, Dongxing Zhang

Electronic Thesis and Dissertation Repository

There has been a surge in interest of 3D printing technology in the recent 5 years with respect to the equipment and materials, because this technology allows one to create sophisticated and customized parts in a manner that is more efficient regarding both material and time consumption. However, 3D printing has not yet become a mainstream technology within the established manufacturing routes. One primary factor accounting for this slow progress is the lack of a broad variety of 3D printable materials, resulting in limited functions of 3D printed parts.

To bridge this gap, I present an integrated strategy to fabricate …


Optimization Of The Hot Embossing Parameters And Sintering Characterization For Alumina/Berea Sandstone Sintering, Justin F. Robbins Aug 2017

Optimization Of The Hot Embossing Parameters And Sintering Characterization For Alumina/Berea Sandstone Sintering, Justin F. Robbins

LSU Master's Theses

The purpose of this study is to investigate the process of hot embossing on alumina based ceramics as a cost-efficient procedure for manufacturing microfluidic testing components. Alumina ceramics were used as an exploratory phase for the final objective of the project, manufacturing of Berea sandstone based ceramic samples. Previous research has shown potential in using hot embossing on Alumina based ceramics; however, complications with extrusion and micro-structure quality were observed. For this reason, the research performed aimed to produce Berea Sandstone based components by first improving upon the embossing quality of alumina ceramics.

The thesis first investigates changes in the …


The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco Aug 2017

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.


Additive Manufacturing Process Of 3d Polyaniline Transducers Via Direct Ink Writing, Frederick Benjamin Holness Aug 2017

Additive Manufacturing Process Of 3d Polyaniline Transducers Via Direct Ink Writing, Frederick Benjamin Holness

Electronic Thesis and Dissertation Repository

Electroactive polymers exhibit a change in properties, typically size or shape, in response to electrical stimuli. One class of electroactive polymer of particular interest are the conjugated polymers, whose conjugated backbone structure imparts electrical conductivity. However, this structure imposes processing limitations restricting their form to 2D structures. To overcome this, we develop specially formulated polyaniline- based blends via counter-ion induced thermal doping for the fabrication of 3D conductive structures via direct ink writing. This approach employs multi-material extrusion for the production of structures with passive and active features, rapid device fabrication, and improved design freedom. A model of the thermal …


Analysis Of Variable Insensitive Friction Stir Welding Parameters, Robert L. Marrero Jr Aug 2017

Analysis Of Variable Insensitive Friction Stir Welding Parameters, Robert L. Marrero Jr

University of New Orleans Theses and Dissertations

Friction Stir Welding (FSW) was used to perform a Design of Experiment (DOE) to determine the welding parameters effects on yielding consistent mechanical properties across the length of the weld. The travel speed was varied across set forge force and RPM conditions, to find a dataset that will yield consistent mechanical properties independent of the travel speed. Six different welds were completed on two different aluminum panels, the advancing side being Aluminum alloy 2195-T8 at a thickness of .350”, with the retreating side being Aluminum alloy 2219-T851 with a gauge thickness of .360”. A Left-hand Right-hand self-reacting pin tool was …


Building Zr-Based Metallic Glass Part On Ti-6al-4v Substrate By Laser-Foil-Printing Additive Manufacturing, Yingqi Li, Yiyu Shen, Ming-Chuan Leu, Hai-Lung Tsai Aug 2017

Building Zr-Based Metallic Glass Part On Ti-6al-4v Substrate By Laser-Foil-Printing Additive Manufacturing, Yingqi Li, Yiyu Shen, Ming-Chuan Leu, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Through using Zr intermediate layers, Zr52.5Ti5Al10Ni14.6Cu17.9 metallic glass (MG) parts are successfully built on Ti-6Al-4V substrates by laser-foil-printing (LFP) additive manufacturing technology in which MG foils are laser welded layer-by-layer onto the substrate. The printed MG part is free of porosity, cracking and crystallization; additionally, its glass transition temperature, crystallization temperature, micro-hardness, and tensile strength are very similar to the original MG material. The Zr intermediate layers are aimed at preventing direct interaction between the first layer of MG foil and the Ti substrate; otherwise, the welded MG foils would peel …