Manufacturing Commons^™

An Investigation Of High-Speed Consolidation And Repair Of Carbon Fiber - Epoxy Composites Through Ultrasonic Welding, David A. Hoskins

LSU Master's Theses

Adhesive repair of carbon fiber composite structures is commonly done on damaged structures to extend the service life. This method requires careful preparation of the damaged surface with intricate steps to ensure good bonding between the repair patch and the parent structure by means of an adhesive film. As with many forms of composite manufacturing, it is required to perform vacuum bagging, debulking, and a heated cure depending on the resin. All these steps make the repair process costly and time consuming.

In this present work, an alternative method of repair is investigated which explores the experimental feasibility of using …

Effective Elastic Properties Of Additively Manufactured Metallic Lattice Structures: Unit-Cell Modeling, Okanmisope Fashanu, David Murphy, Myranda Spratt, Joseph William Newkirk, K. Chandrashekhara, Ben Brown, John Porter

Materials Science and Engineering Faculty Research & Creative Works

Lattice structures are lightweight materials, which exhibit a unique combination of properties such as air and water permeability, energy and acoustic absorption, low thermal conductivity, and electrical insulation. In this work, unit-cell homogenization was used to predict the effective elastic moduli of octet-truss (OT) lattice structures manufactured using selective laser melting (SLM). OT structures were manufactured using a Renishaw AM 250 SLM machine with various relative densities. Compression test was carried out at strain rate 5 x 10^-3 m^-1 using an MTS frame. Finite element analysis was used in the determination of the OT’s effective elastic properties. Results …

Comparison Of Fatigue Performance Between Additively Manufactured And Wrought 304l Stainless Steel Using A Novel Fatigue Test Setup, M. M. Parvez, Y. Chen, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

In this research, a novel adaptive controlled fatigue testing machine was designed for bending type high cycle fatigue test. A unique dual gauge section Krouse type mini specimen was designed for simply supported transverse bending. Displacement controlled fatigue tests were implemented using an electromechanical actuator. The variation in the control signal and load observed during the test provides unique insights into realizing the deterioration of the specimen due to fatigue. These analyses were utilized to compare the fatigue performance of wrought and additively manufactured 304L stainless steel. The influence of the build direction on fatigue performance was also investigated by …

Compressive And Bending Performance Of Selectively Laser Melted Alsi10mg Structures, D. Murphy, O. Fashanu, Myranda Spratt, Joseph William Newkirk, K. Chandrashekhara, H. Misak, D. Klenosky

Materials Science and Engineering Faculty Research & Creative Works

Selective laser melting (SLM) is a widely used additive manufacturing technique that effectively manufactures complex geometries such as cellular structures. However, challenges such as anisotropy and mechanical property variation are commonly found due to process parameters. In a bid to utilize this method for the commercial production of cellular structures, it is important to understand the behavior of a material under different loading conditions. In this work, the behavior of additively manufactured AlSi10Mg under compression, bending, and tension loads was investigated. Vertical and horizontal build directions are compared for each type of loading. Specimens were manufactured using the reduced build …

Elevated Temperature Mechanical And Microstructural Characterization Of Slm Ss304l, G. R. Hecht, Sriram Praneeth Isanaka, Joseph William Newkirk

Materials Science and Engineering Faculty Research & Creative Works

SLM built SS304L was annealed and water quenched to minimize residual stress and avoid carbide precipitation. Mini-tensile characterization of strength and elongation at temperature conditions up to 800°C, along with observations of the associated microstructural transformations were utilized to understand the changes produced in SLM SS304L. As-built and annealed specimens were found to exhibit decreasing strength and elongation with increasing temperature as expected. Carbide precipitates appeared after short times at high temperatures within both as-built and annealed specimens for all cases, but no brittle intermetallic phase development was observed for any of the temperatures investigated. While the lack of Sigma, …

Development Of Experimental And Finite Element Models To Show Size Effects In The Forming Of Thin Sheet Metals, Jeffrey D. Morris

University of New Orleans Theses and Dissertations

Abstract

An experimental method was developed that demonstrated the size effects in forming thin sheet metals, and a finite element model was developed to predict the effects demonstrated by the experiment. A universal testing machine (UTM) was used to form aluminum and copper of varying thicknesses (less than 1mm) into a hemispherical dome. A stereolithography additive manufacturing technology was used to fabricate the punch and die from a UV curing resin. There was agreement between the experimental and numerical models. The results showed that geometric size effects were significant for both materials, and these effects increased as the thickness of …

A Displacement Controlled Fatigue Test Method For Additively Manufactured Materials, Mohammad Masud Parvez, Yitao Chen, Sreekar Karnati, Connor Coward, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

A novel adaptive displacement-controlled test setup was developed for fatigue testing on mini specimens. In property characterization of additive manufacturing materials, mini specimens are preferred due to the specimen preparation, and manufacturing cost but mini specimens demonstrate higher fatigue strength than standard specimens due to the lower probability of material defects resulting in fatigue. In this study, a dual gauge section Krouse type mini specimen was designed to conduct fatigue tests on additively manufactured materials. The large surface area of the specimen with a constant stress distribution and increased control volume as the gauge section may capture all different types …

Stress Corrosion Cracking Resistance Of Cold-Sprayed Al 6061 Deposits Using A Newly Developed Test Fixture, Mala M. Sharma, Jeremy Schreiber, Timothy Eden, Victor Champagne

Faculty Journal Articles

The stress corrosion cracking (SCC) response of Al 6061 bulk deposits produced by high-pressure cold spray (HPCS) was investigated and compared to commercial wrought Al 6061-T6 material. Representative tensile coupons were stressed to 25%, 65% and 85% of their respective yield strength and exposed to ASTM B117 salt fog for 90 days. After exposure, the samples were mechanically tested to failure, and subsequently investigated for stress corrosion cracking via optical and scanning electron microscopy with energy-dispersive X-ray spectroscopy (EDS). The results were compared to the wrought Al 6061-T6 properties and correlated with the observed microstructures. Wrought samples showed the initiation …

Bioprinting With Human Stem Cell-Laden Alginate-Gelatin Bioink And Bioactive Glass For Tissue Engineering, Krishna C. R. Kolan, Julie A. Semon, Bradley Bromet, D. E. Day, Ming-Chuan Leu

Biological Sciences Faculty Research & Creative Works

Three-dimensional (3D) bioprinting technologies have shown great potential in the fabrication of 3D models for different human tissues. Stem cells are an attractive cell source in tissue engineering as they can be directed by material and environmental cues to differentiate into multiple cell types for tissue repair and regeneration. In this study, we investigate the viability of human adipose-derived mesenchymal stem cells (ASCs) in alginate-gelatin (Alg-Gel) hydrogel bioprinted with or without bioactive glass. Highly angiogenic borate bioactive glass (13-93B3) in 50 wt% is added to polycaprolactone (PCL) to fabricate scaffolds using a solvent-based extrusion 3D bioprinting technique. The fabricated scaffolds …

Modifying Casting Parameters To Improve The High Temperature Ductility Of Investment Cast Nickel-Based Superalloy Pwa 1455, Lars Alexander Hedin, Cole Magnum Introligator

Materials Engineering

PCC Structurals, an industry leader in superalloy investment castings, has observed inconsistencies in the stress rupture performance of polycrystalline nickel-based superalloy PWA 1455. PCC has changed their casting parameters to reduce the thermal gradient during cooling but have been unable to correlate these changes with an increase in stress rupture elongation. Metallographic examination of past samples indicated microstructures composed of non- equiaxed dendritic grains with mean diameter of .021 inches along the test axis. A similar study on polycrystalline superalloys has indicated that excessive superheat temperatures above the liquidus can result in large grains identical to those observed, limiting the …

Design Of Natural Composite I-Beam For Sampe 2019, Brian Harkness

Honors Theses

In recent years, the demand for high performance, lightweight, fiber-reinforced composites have grown substantially. Fiberglass and carbon fiber have exemplary material properties that meet the demand and have set the industry standard for performance materials. Although these materials meet their design function, they suffer from high environmental impacts throughout their life cycle and are not cost effective to produce. Flax fiber composites have comparable properties to fiberglass but can be produced more efficiently and production requires much less energy consumption. Flax is a readily available, renewable material that will easily biodegrade once it is the end of its useful life …

Evaluation Of Tensile Properties For Selective Laser Melted 316l Stainless Steel And The Influence Of Inherent Process Features, Paul Swartz

Master's Theses

Optimal print parameters for additively manufacturing 316L stainless steel using selective laser melting (SLM) at Cal Poly had previously been identified. In order to further support the viability of the current settings, tensile material characteristics were needed. Furthermore, reliable performance of the as-printed material had to be demonstrated. Any influence on the static performance of parts in the as-printed condition inherent to the SLM manufacturing process itself needed to be identified. Tensile testing was conducted to determine the properties of material in the as-printed condition. So as to have confidence in the experimental results, other investigations were also conducted to …

Design And Control Of Fiber Encapsulation Additive Manufacturing, Matt Saari

Mechanical Engineering Research Theses and Dissertations

This work presents the design, development, and analysis of the Fiber Encapsulation Additive Manufacturing (FEAM) system developed at the Laboratory for Additive Manufacturing Robotics \& Automation at the Lyle School of Engineering at Southern Methodist University. The innovation introduced by FEAM is the ability to insert a continuous fiber of different material into the flowing extrudate. Correctly positioning the fiber feed inside the extrudate while turning the fiber in arbitrary directions is a critical aspect of the technology. This will allow for the full exploitation of the capabilities of the FEAM technology to produce robotic components that actuate and sense. …

Additive Manufacturing Of High Performance Flexible Thermoelectric Generators Using Nanoparticle Inks, Tony Valayil Varghese

Boise State University Theses and Dissertations

Flexible thermoelectric devices are attractive power sources for the growing demand of flexible electronics and sensors. Thermoelectric generators have an advantage due to no moving parts, silent operation and constant power production with a thermal gradient.

Conventional thermoelectric devices are rigid and fabricated using complex and relatively costly manufacturing processes, presenting a barrier to increase the market share of this technology. To overcome such barriers, this work focuses on developing near ambient-temperature flexible thermoelectric generators using relatively low-cost additive manufacturing processes. A screen printable ink was developed for transforming nanoparticle ink into high-performance flexible thermoelectric generators with a peak thermoelectric …

Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon

McKelvey School of Engineering Theses & Dissertations

Carbon fiber reinforced thermoplastic (CFRTP) composites are becoming increasingly attractive materials in manufacturing due to their lightweight nature, mechanical strength, and corrosion resistance. Surface activation of these materials is usually required during processing to increase the bond strength of assemblies (aerospace and automotive industries) or improve adhesion with implants (biomedical industry). Industrially-relevant, nondestructive quality control methods for assessing the activation state of these materials do not currently exist, however. Applying principles discovered through the use of scanning probe microscopy, a multiple-probe Kelvin scanning (MPKS) device has been developed that can assess the uniformity of the activation state of plasma-treated CFRTP …

A Study On Ultrasonic Energy Assisted Metal Processing : Its Correeltion With Microstructure And Properties, And Its Application To Additive Manufacturing., Anagh Deshpande

Electronic Theses and Dissertations

Additive manufacturing or 3d printing is the process of constructing a 3-dimensional object layer-by-layer. This additive approach to manufacturing has enabled fabrication of complex components directly from a computer model (or a CAD model). The process has now matured from its earlier version of being a rapid prototyping tool to a technology that can fabricate service-ready components. Development of low-cost polymer additive manufacturing printers enabled by open source Fused Deposition Modeling (FDM) printers and printers of other technologies like SLA and binder jetting has made polymer additive manufacturing accessible and affordable. But the metal additive manufacturing technologies are still expensive …

Method And Apparatus For Fabricating Ceramic And Metal Components Via Additive Manufacturing With Uniform Layered Radiation Drying, Ming-Chuan Leu, Amir Ghazanfari, Wenbin Li, Greg Hilmas, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A freeform extrusion fabrication process for producing three - dimensional ceramic, metal and functionally gradient composite objects, including the steps of filling a plurality of paste sources with a respective plurality of aqueous paste compositions, operationally connecting respective syringes containing respective aqueous paste compositions to a mix ing chamber, moving a first aqueous paste composition from a first respective paste source into the mixing chamber, moving a second aqueous paste composition from a second respective paste source into the mixing chamber, mixing the first and second aqueous paste compositions to define a first admixture having a first admixture composition, extruding …

Analytical And Experimental Study Of Laser Cladding Of Ni/Wc Metal Matrix Powders Reinforced With Rare Earth Elements Using A High Power Direct Diode Laser, Mohammed Sayeed

Mechanical Engineering Research Theses and Dissertations

The corrosion and wear are major limiting factors for steel in the harsh environments and can be controlled by depositing protective passive coatings. Nickel based alloy cladding of steel offers a solution by enabling better corrosion and wear resistance, and high bonding strength. The laser surface cladding of steel was conducted using a high power direct diode laser. Layers of tungsten carbide in Ni (40%Ni-60%WC) combined with 1% and 2% Lanthanum Oxide (La₂O₃) and Cerium Oxide (CeO₂) were deposited on ASTM A36 steel substrate. The X-ray diffraction and scanning electron microscopy were employed to …

Process Parameter Development Of Additively Manufactured Af9628 Weapons Steel, Erin M. Hager

Theses and Dissertations

The manufacture of components in Additive Manufacturing processes is limited by the range of materials available. Qualification of materials for Additive Manufacturing is time intensive, and is often specific to a single type of machine. In this study, an approach to selecting power, speed, and hatch spacing values for a newly powderized material, AF9628 weapons steel, is described that results in highly dense (>99.9%) parts on an MLab 200R Cusing. Initial power and speed values used in a weld track study were selected based on a survey of parameters used on similar materials, with a focus on the energy …

Microscale Metal Forming: Mesoscopic Size Effect, Extrusion And Molding, Bin Zhang

LSU Doctoral Dissertations

The continuing trend of metallic device and product miniaturization has motivated studies on microscale metal forming technologies. A better understanding of materials’ mechanical response and deformation behavior is of importance for the design and operation of micro metal forming processes. In this dissertation, uniaxial compression testing was conducted on Al ring and pillar specimens with characteristic dimensions at meso to micro scales. The experimental data reveal inadequacies of the existing surface layer model and provides a baseline for delineating deformation mechanisms in micro metal forming operations. Microscale reverse extrusion experiment was carried out on Cu and Al rod specimens with …

A Total Life Cycle Approach For Developing Predictive Design Methodologies To Optimize Product Performance, Buddhika M. Hapuwatte, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainable products must be designed by considering how design decisions impact their total life cycle (TLC) sustainability content. Even more so important when designing products to incorporate the technological elements of sustainable manufacturing, the 6Rs (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacture), to achieve Circular Economy (CE). This paper presents the preliminary work of an ongoing research project on developing a novel framework incorporating predictive models with TLC considerations. This unique approach develops and integrates models with associated risks, and optimizes for maximizing the sustainability benefits due to design decisions. Such predictive capability is extremely useful for process planning, where …

Stair Climbing Hand Truck, James Mcpherson

All Undergraduate Projects

Abstract

Getting a heavy object up a flight of stairs usually requires a team of two or more people. Even with a team of people, the task is often still difficult, dangerous, and possibly insurmountable by one person. This problem is especially prevalent in for those who are moving into apartment complexes. Most apartment complexes have many buildings with two or more floors of living quarters, and elevators are often missing. This project sought to offer a solution to this problem. The solution in question; a motorized hand-truck with 2, trigonal planar pinwheels in place of the stock wheels. The …

Process Sustainability Evaluation For Manufacturing Of A Component With The 6r Application, Ana E. Bonilla Hernández, Tao Lu, Tomas Beno, Claes Fredriksson, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainability in manufacturing can be evaluated at product, process and system levels. The 6R methodology for sustainability enhancement in manufacturing processes includes: reduced use of materials, energy, water and other resources; reusing of products/components; recovery and recycling of materials/components; remanufacturing of products; and redesigning of products to utilize recovered materials/resources. Although manufacturing processes can be evaluated by their productivity, quality and cost, process sustainability assessment makes it a complete evaluation. This paper presents a 6R-based evaluation method for sustainable manufacturing in terms of specific metrics within six major metrics clusters: environmental impact, energy consumption, waste management, cost, resource utilization and …

Design And Process Of 3d-Printed Parts Using Composite Theory, Jordan Garcia

Theses and Dissertations--Mechanical Engineering

3D printing is a revolutionary manufacturing method that allows the productions of engineering parts almost directly from modeling software on a computer. With 3D printing technology, future manufacturing could become vastly efficient. However, it is observed that the procedures used in 3D printing differ substantially among the printers and from those used in conventional manufacturing. In this thesis, the mechanical properties of engineering products fabricated by 3D printing were comprehensively evaluated and then compared with those made by conventional manufacturing. Three open-source 3D printers, i.e., the Flash Forge Dreamer, the Tevo Tornado, and the Prusa, were used to fabricate the …

Investigation Of Chip-Form And Tool-Wear In Turning Of Hardened Af9628 Alloy Under Various Cooling And Lubrication Conditions, Jason Wolf

Theses and Dissertations--Manufacturing Systems Engineering

Next generation defense and commercial applications for structural steels require new alloys that eliminate or reduce critical elements from their composition to lower cost and improve manufacturability, while maintaining or exceeding high strength and toughness requirements. A new alloy, denoted as AF9628, has recently been developed for this purpose and its manufacturing characteristics and the material response in component manufacturing must be fully understood.

In the present study, hardened AF9628 alloy was turned with a coated carbide cutting tool under fixed cutting speed, feed rate, and depth of cut parameters. This work focuses on chip-form and tool-wear analysis to understand, …

3d Textile Preforms And Composites For Aircraft Strcutures: A Review, Abbasali Saboktakin

International Journal of Aviation, Aeronautics, and Aerospace

Over the last decades, the development of 3D textile composites has been driven the structures developed to overcome disadvantages of 2D laminates such as the needs of reducing fabrication cost, increasing through-thickness mechanical properties, and improving impact damage tolerance. 3D woven, stitched, knitted and braided preforms have been used as composites reinforcement for these types of composites. In this paper, advantages and disadvantages of each of them have been comprehensively discussed. The fabric architects and their specification in particular stitched preforms and their deformation mode for aerospace applications have been reviewed. Exact insight into various types of damage in textile …

Autojack - Hydraulic Powertrain System, Tyce Vu

All Undergraduate Projects

A primary problem for mechanics and automotive enthusiasts is the risk associated with lifting and securing a vehicle with conventional jack stands. Often times, improper jack-stand installation results in the vehicle collapsing unexpectedly, causing injury and/or death. This problem can be minimized through the application of a newly re-designed vehicle lifting system. The conventional method for lifting cars is time consuming and can be unsafe in many circumstances. A better, safer, and more efficient lift design was needed; the AutoJack. The approach of the AutoJack design was entirely focused on the safety of lifting a vehicle. Safety was improved by …

Enhanced Surface Integrity With Thermally Stable Residual Stress Fields And Nanostructures In Cryogenic Processing Of Titanium Alloy Ti-6al-4v, James R. Caudill

Theses and Dissertations--Mechanical Engineering

Burnishing is a chipless finishing process used to improve surface integrity by severe plastic deformation (SPD) of surface asperities. As surface integrity in large measure defines the functional performance and fatigue life of aerospace alloys, burnishing is thus a means of increasing the fatigue life of critical components, such as turbine and compressor blades in gas turbine engines. Therefore, the primary objective of this dissertation is to characterize the burnishing-induced surface integrity of Ti-6Al-4V alloy in terms of the implemented processing parameters. As the impact of cooling mechanisms on surface integrity from SPD processing is largely unexplored, a particular emphasis …

Carbon Fiber Monocoque, Dan Brown, Leland Hoffman

Williams Honors College, Honors Research Projects

The University of Akron’s Human Powered Vehicle Team designed a high performing, fully functioning vehicle that is safe, efficient, and practical for the 2018-2019 season. These objectives were the main priorities when it came to the initial stages of designing the vehicle. In addition, the vehicle was designed in accordance with the ASME 2019 Human Powered Vehicle Challenge guidelines to satisfy all the rules and requirements. Additional priorities have been created to teach practical engineering skills and techniques to the students participating in the project through different points in the production process including research, vehicle design, construction, and testing.

The …

Generator Design: A Study Of Optimized Airflow, Rachel Wattleworth

Williams Honors College, Honors Research Projects

The core goal of this project was to prototype, test, and evaluate a new type of fan for the Safran Electrical & Power air-cooled generators. The idea of a new fan being made for these two generators arose when they were not adhering to design requirements. A base mixed-flow fan was created to test on multiple generators. Upon creating a prototype, it will be tested to prove if it can increase the air flow, decrease temperatures, and increase power and life of the machines. They all proved to be successful and achieve the main objectives for this project. Data such …