Engineering Commons^™

Rheological Properties Of Two Stainless Steel 316l Powders For Additive Manufacturing, Haijun Gong, Xiaodong Xing, Hengfeng Gu

Department of Manufacturing Engineering Faculty Research and Publications

This study measures the rheological properties of two stainless steel 316L powders which are used for the powder-bed-fusion based additive manufacturing process. The purpose is to evaluate the newly acquired powder in comparison with the used and recycled powder, so that both powders can be mixed with each other to supplement the powder usage. The powder rheology properties, such as dynamic property, bulk property, and shear property, are tested and compared. The results and analysis confirm the compatibility of powder mixing.

Ua66/2 Ogden College Of Science & Engineering Architectural & Manufacturing Sciences, Wku Archives

WKU Archives Collection Inventories

Records created by the Architectural & Manufacturing Sciences.

Files are arranged in the following subseries:

1. Administration
2. Publications
3. Centers & Institutes

Ua66/1/5 Ogden College Of Science & Engineering Dean's Office Centers, Wku Archives

WKU Archives Collection Inventories

Records created by and about centers associated with the Dean's office in the Ogden College of Science & Engineering.

Hydrogen Fuel Cell Gasket Handling And Sorting With Machine Vision Integrated Dual Arm Robot, Devin C. Fowler

Electronic Theses and Dissertations

Recently demonstrated robotic assembling technologies for fuel cell stacks used fuel cell components manually pre-arranged in stacks (presenters), all oriented in the same position. Identifying the original orientation of fuel cell components and loading them in stacks for a subsequent automated assembly process is a difficult, repetitive work cycle which if done manually, deceives the advantages offered by automated fabrication technologies of fuel cell components and by robotic assembly processes. We present an innovative robotic technology which enables the integration of automated fabrication processes of fuel cell components with robotic assembly of fuel cell stacks into a fully automated fuel …

Modeling And Simulation Of The Thermoforming Process In Thermoplastic-Matrix Composite Materials, Philip M. Bean

Electronic Theses and Dissertations

Thermoplastic-matrix composite materials have unique advantages over traditional thermosets including faster processing, improved fracture toughness, and recyclability. These and other benefits have caused increasing interest in the use of these materials in both aerospace and automotive industries. Due to the differences in behavior, these materials require a different type of manufacturing process to thermoset matrix composites. This manufacturing process generally involves using pre manufactured tape-layers. These layers, containing both thermoplastic-matrix and fiber-reinforcement, are aligned to the desired orientation, and stacked up into a “tailored blank” using an automated tape layup machine. They are then heated to the thermoplastic melting temperature …

Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut

Graduate Theses and Dissertations

The underlying physics of failure are critical in assessing the long term reliability of power packages in their intended field applications, yet traditional reliability determination methods are largely inadequate when considering thermomechanical failures. With current reliability determination methods, long test durations, high costs, and a conglomerate of concurrent reliability degrading threat factors make effective understanding of device reliability difficult and expensive. In this work, an alternative reliability testing apparatus and associated protocol was developed to address these concerns; targeting rapid testing times with minimal cost while preserving fatigue life prediction accuracy. Two test stands were fabricated to evaluate device reliability …

All-Terrain Storage Surfboard Carts, Ben M. Kennedy, Danny Riedeman, Roberto Gonzalez

Mechanical Engineering

All Terrain Storage consists of three mechanical engineering students: Roberto Gonzalez, Ben Kennedy, and Danny Riedeman. The goal of All Terrain Storage is to design and create two portable storage devices for the non-profit organization AmpSurf. AmpSurf helps veterans, people with disabilities, and anyone else who could be helped through adaptive surfing and other outdoor activities. Their current method of storing and transporting equipment for events is carrying it from the trailer in the parking lot through the sand onto the beach. This document will provide: a more thorough introduction to AmpSurf and the project, the objectives, background information, the …

Process-Property-Microstructure Relationships In Laser-Powder Bed Fusion Of 420 Stainless Steel., Subrata Deb Nath

Electronic Theses and Dissertations

Laser-powder bed fusion (L-PBF) is an additive manufacturing technique for fabricating metal components with complex design and customized features. However, only a limited number of materials have been widely studied using L-PBF. AISI 420 stainless steel, an alloy with a useful combination of high strength, hardness, and corrosion resistance, is an example of one such material where few L-PBF investigations have emerged to date. In this dissertation, L-PBF experiments were conducted using 420 stainless steel powders to understand the effects of chemical composition, particle size distribution and processing parameters on ensuing physical, mechanical and corrosion properties and microstructure in comparison …

Photochemical Etching Of Nitrided Stainless Steel Piston Rings, Steven Sonntag

Mechanical Engineering Undergraduate Honors Theses

Piston rings are designed to provide a seal between the piston and the cylinder wall of internal combustion engines, keeping oil from the crankcase from getting into the combustion chamber. This means piston rings are the main point of contact between the piston and the cylinder wall, which causes the piston to experience high amounts of friction and wear. By texturing the surfaces of the cylinder wall and/or the piston ring, the amount of contact area can be reduced, allowing for less friction, slower wear, and better gas mileage. In this thesis experiments, photochemical etching processes were developed to etch …

Optimization Of The Practice Of Slow Cooling Steel Bars: A Redesign And Modernization Of Materials, Eryn Johnston

Mechanical Engineering Undergraduate Honors Theses

Throughout the process of steel making, certain grades of steel are a higher risk for defects caused by the inability to quickly diffuse hydrogen through the steel when cooled to room temperature at a normal rate based on the ambient air temperature. To reduce the hydrogen flaking defects that are caused due to hydrogen entrapment in the steel, the process of slow cooling is utilized. This process reduces the cooling rate of steel bars by keeping them at a higher temperature for extended periods and in turn gives the hydrogen a chance to fully dissipate from the steel. In many …

A Scalable, Chunk-Based Slicer For Cooperative 3d Printing, Jace J. Mcpherson

Computer Science and Computer Engineering Undergraduate Honors Theses

Cooperative 3D printing is an emerging technology that aims to increase the 3D printing speed and to overcome the size limit of the printable object by having multiple mobile 3D printers (printhead-carrying mobile robots) work together on a single print job on a factory floor. It differs from traditional layer-by-layer 3D printing due to requiring multiple mobile printers to work simultaneously without interfering with each other. Therefore, a new approach for slicing a digital model and generating commands for the mobile printers is needed, which has not been discussed in literature before. We propose a chunk-by-chunk based slicer that divides …

A Systematic Approach To High Blood Pressure Risk Analysis And Healthcare Cost Reduction In Young Adults [Metodología Sistemática Para El Análisis De Riesgo Y Reducción De Costos De Servicios Médicos De Hipertensión En Adultos Jóvenes], Francisco Rafael Torres Diaz

Theses and Dissertations

The purpose of this research is to utilize publicly available data to estimate the current rate of occurrence of undiagnosed High Blood Pressure (HBP) in young adults (18 to 24 years old) and the out-of-pocket healthcare expenses associated with complications of HBP, to provide feasible alternatives to mitigate the effects on a region's economy. This has been done by building a Risk Factor Simulation Model that utilizes known HBP risk factors’ correlation to HBP, insurance coverage data, and rate of diagnosis to formulate the average Risk Factor Value for a region, which through an Annual Expected Cost Function estimates the …

Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe

Mechanical Engineering

Reinventing the Wheel selected tires and designed wheels for the 2018 Cal Poly, San Luis Obispo Formula SAE combustion vehicle. Available tire options were evaluated for steady-state and transient performance as well as vehicle integration. A single-piece composite wheel with hollow spokes was designed to meet stiffness, strength, and tolerance requirements. A detailed study of wheel loading and geometric structural efficiency was performed. Finite element analysis was used to iterate the geometry and laminate. A two-piece male mold was designed and machined to manufacture the wheel. Removable silicone inserts were used to create the hollow spokes.

Single Arm Recumbent Bicycle, Alexander Borsotti, Ryan Westermann, Sean Liston

Mechanical Engineering

The goal of this report is to outline and cover the scope of work for the Single Arm Recumbent Bicycle Senior Project. The report will give an introduction of the problem, a background of the existing research or products relating to our project, the objectives of our project, our project management plan, our final design, manufacturing, testing, our project management, and final recommendations for improving the final design. The team is being supported by the Quality of Life Program, a non-profit organization that works to improve the lives of those injured in duty while serving our nation.

Up until now, …

Daimscale — 1:14th Tractor-Trailer For Testing Driver Assistance Technology, Christopher Marrale, Jase Sasaki, Devin Bodmer

Mechanical Engineering

Active driver assistance systems are becoming increasingly wide-spread throughout the automotive industry due to their potential for safer roads and decreased costs of transportation, but testing these systems on real trucks can be time consuming, dangerous, and costly. Testing these systems on a small-scale tractor-trailer combination will lead to faster and more efficient development of driver assistance systems and can be used by both engineers and students, leading to a larger field of experienced developers to improve these systems.

Our goal will be to design, manufacture, and build a scale 6x2 model of the tractor portion of a Daimler semi-truck …

Transcribing Braille Code: Learning Equations Across Platforms, Deegan Atha, Courtney Balogh

Purdue Journal of Service-Learning and International Engagement

Deegan Atha, a graduating senior in electrical engineering and a future engineer, is interested in human-centered design and developing technology that helps students engage and be successful in STEM.

Courtney Balogh, a junior in mechanical engineering, is interested in human-centered design and the importance it plays in product development. Deegan and Courtney are members of the Purdue EPICS project, Learning Equations Across Platforms (LEAP). They partnered with the Indiana School for the Blind and Visually Impaired (ISBVI) to develop a braille transcription device and web application that converts braille to print in real time.

Model-Based Predictive Analytics For Additive And Smart Manufacturing, Zhuo Yang

Doctoral Dissertations

Qualification and certification for additive and smart manufacturing systems can be uncertain and very costly. Using available historical data can mitigate some costs of producing and testing sample parts. However, use of such data lacks the flexibility to represent specific new problems which decreases predictive accuracy and efficiency. To address these compelling needs, in this dissertation modeling techniques are introduced that can proactively estimate results expected from additive and smart manufacturing processes swiftly and with practical levels of accuracy and reliability. More specifically, this research addresses the current challenges and limitations posed by use of available data and the high …

Electroplating Of Copper On Tungsten Powder, Richard Berdos

Masters Theses

Strengthening, resistant and shielding properties, to name a few, can be achieved by implementing a surface material coating onto an engineering component. Various elements of these compounded parts can augment the functionality of the part, such as, increased life time and more interactive surfaces. Tungsten has proven to be a challenge to plate with other metals, but if done correctly, the results can allow for the cold spray of tungsten. Cold spraying tungsten particles alone provides a challenge because the powder is too hard and instead of adhering, it erodes the surface it is attempting to plate. Coating tungsten in …

Three-Dimensional Forming Of Multi-Layered Materials: Material Heat Response And Quality Aspects, Sami-Seppo Ovaska, Pavel Geydt, Ville Leminen, Johanna Lyytikäinen, Sami Matthews, Panu Tanninen, Malte Wallmeier, Marek Hauptmann, Kaj Backfolk

Journal of Applied Packaging Research

The micro- and macrostructural changes occurring in multi-layered substrates during three-dimensional forming were studied by atomic force microscopy (AFM), scanning electron microscopy (SEM) and optical analyses. Particular attention was paid to heat-induced deformations at the interface between of polymeric coating layer and the paperboard. With excessive heat transfer, occasional delamination of polyethylene terephthalate (PET) coating from the paperboard was observed. The mechanism behind delamination was studied in detail in-situ with an AFM at temperatures relevant to the converting process. Based on the analysis, the delamination could partially be linked to the widening of the initially-existing nano-scale cracks at the coating-paperboard …

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

Buenaventura "Ven" Basco

No abstract provided.

Improving Sheet Molding Compound, Zebulon G. Mcreynolds

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Zebulon McReynolds

An important attribute of the compression molding process is the requirement of (Sheet Molding Compound) SMC. The fibers, commonly glass or carbon fibers, are impregnated with thermoset resin and collected in continuous form on a conveyor belt. The SMC charge is rolled between rollers to wet out the fibers with resin. The SMC charge is then compression molded to a desired part reflecting the designed mold. The part could be an automotive part or any other industrial applicable part. Compression molding with fibers and polymers is the largest component of most of the manufacturing industries in the world. …

Modular Crates – A Holistic Design Approach For Optimizing Cube Size In Industrial Packaging, Marshal Louie, Kumar B

Journal of Applied Packaging Research

Global market is a field where all industries strive to provide personalized product for every customer demand in order to compete with their competitors in the business battlefield. Product personalization varies with customer to customer which increases the product variety. When the product size variability is vast, producing packages for every individual product is not only difficult but also increases the design time, production time, total manufacturing cost and inventory cost. For the present scenario, Industrial packages does not opt customizability for variable product sizes. Customized package for personalized product is achievable only by redesigning the existing distribution package with …

Thermo-Physical Modelling And Experimental Analysis Of The Laser-Material Interactions During Cw Laser Polishing, Shirzad Mohajerani

Electronic Thesis and Dissertation Repository

Laser polishing (LP) represents one of the finishing/superfinishing technologies that has experienced a rapid growth over the past two decades. However, while undeniable progress has been achieved on the experimental and/or practical side, the development of the mathematical models continue to be somewhat slower and still dominated by significant simplifying assumptions.

To address this research gap, after identification of underlying thermo-physical processes during LP through a comprehensive literature review, two CFD (Computational Fluid Dynamics) models are developed to simulate the laser-material interactions and eventually predict the final geometry of the irradiated surface. In this context, a 3D CFD model is …

Feasibility Of Hybrid Thermoplastic Composite-Concrete Load Bearing System, Camerin M. Seigars

Electronic Theses and Dissertations

Thermoplastic composites have many advantages over thermoset composites such as being recyclable, rapidly manufacturable, and more impact resistant. The goal of this thesis is to assess the feasibility of using thermoplastic composites in structural applications through literature review, mechanical testing, design of a load-bearing hybrid composite-concrete structures, and the implementation of thermoplastic composites for tensile reinforcement of concrete. The study had four objectives covering the stated goal.

1. Conduct a literature review to direct thermoplastic material selection
2. Characterize thermoplastic material mechanical properties using standardized mechanical testing
3. Design a hybrid composite-reinforced concrete beam, and
4. Develop thermoplastic shear connectors to develop composite action …

Experimental Characterization Of A Direct Metal Deposited Cobalt-Based Alloy On Tool Steel For Component Repair, Xinchang Zhang, Tan Pan, Wei Li, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Die casting dies made of tool steel is subject to impact, abrasion and cyclic thermomechanical loading that delivers damage such as wear, corrosion, and cracking. To repair such defects, materials enveloping the damage need to be machined and refilled. In this study, V-shape defects with varied sidewall inclination angles were prepared on H13 tool steel substrates and refilled with cobalt-based alloy using direct metal deposition (DMD) for superior hardness and wear resistance. The microstructure of rebuild samples was characterized using an optical microscope (OM) and scanning electron microscope (SEM). Elemental distribution from the substrate to deposits was analyzed using energy …

Fabricating Functionally Graded Materials By Ceramic On-Demand Extrusion With Dynamic Mixing, Wenbin Li, Austin J. Martin, Benjamin Kroehler, Alexander M. Henderson, Tieshu Huang, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu

Materials Science and Engineering Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is an extrusion-based additive manufacturing process recently developed for fabricating dense, functional ceramic components. Presented in this paper is a further development of this process focusing on fabrication of functionally graded materials (FGM). A dynamic mixing mechanism was developed for mixing constituent ceramic pastes, and an extrusion control scheme was developed for fabricating specimens with desired material compositions graded in real time. FGM specimens with compositions graded between Al₂O₃ and ZrO₂ were fabricated and ultimately densified by sintering to validate the effectiveness of the CODE process for FGM fabrication. Energy dispersive spectroscopy …

Additive Manufacturing Of Metal Bandpass Filters For Future Radar Receivers, Bradley Grothaus, Dane Huck, Austin T. Sutton, Ming-Chuan Leu, Ben Brown

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Selective laser melting (SLM) is a powder-bed fusion (PBF) process that bonds successive layers of powder with a laser to create components directly from computer-aided design (CAD) files. The additive nature of the SLM process in addition to the use of fine powders facilitates the construction of complex geometries, which has captured the attention of those involved in the design of bandpass filters for radar applications. However, a significant drawback of SLM is its difficulty in fabricating parts with overhangs necessitating the use of support structures, which, if not removed, can greatly impact the performance of bandpass filters. Therefore, in …

Fiber-Fed Printing Of Free-Form Free-Standing Glass Structures, John M. Hostetler, Jason E. Johnson, Jonathan T. Goldstein, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel

Materials Science and Engineering Faculty Research & Creative Works

Additive Manufacturing (AM) of low-profile 2.5D glass structures has been demonstrated using a fiber-fed laser-heated process. In this process, glass fibers with diameters 90-125 μm are supported as they are fed into the intersection of the workpiece and a CO₂ laser beam. The workpiece is positioned by a four-axis CNC stage with coordinated rotational/transitional kinematics. The laser energy at λ = 10.6 μm is coupled to phonon modes in the glass, locally heating it above its working point. The rapid heating and cooling process allows for the deposition of various glasses into free-standing three-dimensional structures such as trusses and …

Mechanical Properties Evaluation Of Ti-6al-4v Thin-Wall Structure Produced By A Hybrid Manufacturing Process, Lei Yan, Wenyuan Cui, Joseph William Newkirk, Frank W. Liou, Eric E. Thomas, Andrew H. Baker, James B. Castle

Materials Science and Engineering Faculty Research & Creative Works

The hybrid manufacturing (HM) process combines the precision of computer numerical control (CNC) and the freeform capability of additive manufacturing to expand the versatility of advanced manufacturing. The intent of this paper is to explore the relationship between HM processing parameters and mechanical properties of the final parts manufactured by one type of HM process that combines laser metal deposition (LMD) and CNC milling. The design of experiment (DOE) is implemented to explore the Ti-6Al-4V thin-wall structure fabrication process with different HM build strategies. Vickers hardness, tensile test, and microstructure analyses are conducted to evaluate the mechanical property variance within …

Development Of An Engineering Diagram For Additively Manufactured Austenitic Stainless Steel Alloys, Zachary T. Hilton, Joseph William Newkirk, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Austenitic stainless steels are the most widely applied types of stainless steels, due to their good weldability and high corrosion resistance. A number of engineering diagrams exist for the purpose of providing insight into the behavior of these steels. Examples of these diagrams are constitution diagrams (aka Schaeffler Diagrams) which are used to approximate the solidification path of the alloy and the amount of retained ferrite in the solidified matrix. Other diagrams are the Suutala diagram, which approximates cracking susceptibility, and microstructural maps, which predict the solidification path by varying a processing parameter, such as cooling rate. By combining these …