Mechanical Engineering Commons^™

Fiber Orientation Prediction And Strength Evaluation Of Composite Spur Gears Reinforced By Discontinuous Fiber, Nawrin Jahan

Electronic Theses and Dissertations

Composite materials have been extensively used for their important role in attenuation of components design, low specific weight, high mechanical performance, and excellent corrosion resistance offer significant advantages over metallic materials. These superlative properties can be attained by tailoring different material in an appropriate combination of the reinforcing phase (carbon fiber, alumina, etc.) and matrix phase (polymer, ceramic, metals, etc.). Carbon fiber reinforced composites are mostly used on intricate stress sensitive structures like wings of aero plane or gear. Amount of fiber, fiber type, and size of the fiber and the orientation of reinforcing fibers directly influence the mechanical properties …

Characterization Of Mechanical Properties Of Gamma Irradiated Additively Manufactured Articles For In-Space Manufacturing, Behzad Rankouhi

Electronic Theses and Dissertations

Recently, additive manufacturing (AM) has opened many doors to engineers across various industries, such as medical, bio-engineering, automotive and recently, aerospace. In an effort to contribute to the development of AM in aerospace industry, a series of experiments were designed to help understand the behavior of 3D printed parts and extend its capabilities and possible uses. The first chapter of this project will focus on understanding the mechanical behavior of additively manufactured articles. In this chapter, a comprehensive effort was undertaken to represent the strength of a 3D printed object as a function of layer thickness by investigating the correlation …

Investigation Of Humidity And Temperature Response Of A Silica Gel Coated Microfiber Coupler, Yuliya Semenova, Gerald Farrell, Dejun Liu

Conference Papers

The humidity and temperature responses of a microfiber coupler (MFC) coated with silica gel are investigated. Two MFC structures with different waist diameters of 2.5 and 3.5 μm were fabricated by fusing and tapering two single-mode fibers using a microheater brushing technique. The influences of the coating thickness and tapered waist diameter on the sensing performance are analyzed. For the proposed sensor with a waist diameter of 2.5 μm and 8-layers thick coating, the change in the relative humidity (RH) results in an exponential blueshift with a maximum sensitivity of 1.6 nm/% RH in the range from 70 to 86% …

Properties Of Partially Stabilized Zirconia Components Fabricated By The Ceramic On-Demand Extrusion Process, Wenbin Li, Amir Ghazanfari, Devin Mcmillen, Ming Leu, Gregory Hilmas, Jeremy Watts

Faculty Publications, Mechanical Engineering

The Ceramic On-Demand Extrusion (CODE) process is a novel additive manufacturing process for fabricating dense ceramic components from aqueous pastes of high solids loading. In this study, 3 mol% Y2O3 stabilized tetragonal zirconia polycrystal (3Y-TZP) parts were fabricated using the CODE process. The parts were then dried in a humidity controlled environmental chamber and sintered under atmospheric pressure. Mechanical properties of the sintered parts were examined using ASTM standard test techniques, including density, Young’s modulus, flexural strength, Weibull modulus, fracture toughness and Vickers hardness. The microstructure was analyzed, and grain size was measured using scanning electron microscopy. The results compared …

Cryogenic Processing Of Al 7050-T7451 Alloy For Improved Surface Integrity, Bo Huang

Theses and Dissertations--Mechanical Engineering

Al 7050-T7451 alloy with good combinations of strength, stress corrosion cracking resistance and toughness, is used broadly in the aerospace/aviation industry for fatigue-critical airframe structural components. However, it is also considered as a highly anisotropic alloy as the crack growth behavior along the short transverse direction is very different from the one in the long transverse direction, due to the inhomogeneous microstructure with the elongated grains distributed in the work material used in the sheet/plate applications. Further processes on these materials are needed to improve its mechanical and material properties and broaden its applications.

The material with ultra-fine or nano …

Fabricating Superhydrophobic And Superoleophobic Surfaces With Multiscale Roughness Using Airbrush And Electrospray, Karam N. Almilaji

Theses and Dissertations

Examples of superhydrophobic surfaces found in nature such as self-cleaning property of lotus leaf and walking on water ability of water strider have led to an extensive investigation in this area over the past few decades. When a water droplet rests on a textured surface, it may either form a liquid-solid-vapor composite interface by which the liquid droplet partially sits on air pockets or it may wet the surface in which the water replaces the trapped air depending on the surface roughness and the surface chemistry. Super water repellent surfaces have numerous applications in our daily life such as drag …

Design Features And Optimization Of Profile Extrusion Dies, Abhishek Sai Erri Pradeep

Dissertations, Master's Theses and Master's Reports

This report deals with design of dies used in the plastic extrusion industry. The design methodology for extrusion dies has evolved over the years with advancement of computing technology. However, the design process is still heavily dependent on the experience of the die designer, and hence is still considered to be more of an art than science. Even for an experienced designer, the time required to design the die and perform consecutive fine tuning iterations is high. In this report, a proprietary optimization code for extrusion dies, .developed by Plastic Flow LLC, was tested and shown to be advantageous over …

The Reconfigurable Machinery Efficient Workspace Analysis Based On The Twist Angles, Ana M. Djuric, Vukica Jovanovic, Mirjana Filipovic, Ljubinko Kevac

Engineering Technology Faculty Publications

A novel methodology for the calculation, visualisation and analysis of the Reconfigurable Machinery Efficient Workspace (RMEW), based on the twist angles, is presented in this paper. The machinery's kinematic parameters are used for calculating the workspace, while the efficient workspace is associated with the machinery's path and includes the end-effector position and orientation. To analyse and visualise many different machinery efficient workspaces at the same time, the calculation is based on the previously developed and validated complex reconfigurable machinery's kinematic structure named n-DOF Global Kinematic Model (n-GKM). An industrial robot is used as an example to demonstrate …

Prediction Of Surface Roughness In Abrasive Waterjet Cutting Of Graphite Composite Using Response Surface Methodology, Prabhakar Bala

Masters Theses

"In the present work, surface roughness after machining of composite material was the main focus of study. Response surface methodology with Box- Behnken experimental design was applied in predicting the surface roughness (R_a) of abrasive waterjet cut 1-inch-thick graphite/epoxy composite. Second order response equations for R_a were generated with minitab, a statistical software as a function of pressure, traverse speed and isolated abrasive mesh size. Influence of each of these factors on the response were analyzed with 3D response surface plots. Abrasive mesh size was also found be a factor influencing Ra along with traverse speed and …

Applications Of Digital Manufacturing In Manufacturing Process Support, Vukica Jovanovic, Mihael Debevec, Niko Herakovic, Alok Verma, Mileta Tomovic

Engineering Technology Faculty Publications

In this study, the authors developed three new approaches and models for improvements related to manufacturing processes. The main focus was on planning in a digital environment before the actual manufacturing process is carried out. The first approach is digital manufacturing, which gives affords the opportunity for performing an entire manufacturing process in a virtual environment. In this way, engineers virtually define, plan, create, monitor, and control all production processes. The planning phase can be done simultaneously, while other manufacturing processes are already in place. In this way, processes can continue with no interruption. Various product lifecycle management tools have …

Mechanical Testing Of Fused Filament 3-D Printed Components For Distributed Manufacturing, Nagendra Gautam Tanikella

Dissertations, Master's Theses and Master's Reports

Fused filament fabrication (FFF)-based open-source 3-D printers offer the potential of decentralized manufacturing both in developing and developed countries. Unfortunately, a severe lack of data and standards relating to material properties and printed components limit this potential. This thesis first investigates the mechanical properties of a wide-range of FFF materials and provides a database of mechanical strength of the materials tested. The results demonstrate that the tensile strength of a 3-D printed specimen depends largely on the mass of the specimen, which provides a means to estimate the strength of 3-D printed components. Then this information is used to evaluate …

The Relationship Of Corporate Financial Performance And Innovation Among Manufacturing Industries, Charlaine T. Chong, Samantha R. Chua, Ma. Catrina S. Dy, Antonio Miguel E. Villavicencio

Angelo King Institute for Economic and Business Studies (AKI)

Innovation is becoming a critical determinant of the survival and advancement of firms. Despite this realization, there is a dearth of literature that tackles the subject matter and its specific role in corporate settings remains vague. Using corporate data on East and Southeast Asian manufacturing firms from 2008 to 2013, this study aims to identify the impact of corporate financial performance on research and development (R&D) expenditure as a measure of innovation. On the whole, the researchers utilized random effects (REM) and fixed effects (FEM) models to establish the relationship between R&D and corporate performance. The researchers, then, identified the …

Composite Model Representation For Computer Aided Design Of Functionally Gradient Materials, Fangquan Wang

Masters Theses

"Functionally Gradient Materials (FGMs) feature smooth transition from one material to another within a single object. FGMs modeling is considered to be one of the new challenges in Computer Aided Design (CAD) area. To overcome this challenge, this thesis presents a composite approach to model FGMs. The input in STL format can be meshed and voxelized in FGMs modeling system. The material composition in each voxel can be generated from multiple different types of control features. And LTI filters including Gaussian Filter and Average Filter are applied to blur default material features in order to generate FGMs inside models. The …

Design Of An Adaptive Force And Stiffness Controlled Compliant Device For Robotic Polishing, Mohammad Masud Parvez

Masters Theses

"Polishing is a repetitive task done in an unhealthy environment. Often more than half of the manufacturing time is required to polish a die. The manual polishing process is a tedious work actively rely on a skilled human worker. Industrial Robot has replaced the human in performing these tasks. For robotic polishing to control the polishing force, an active compliant device is used. Due to the compressibility of air, a pneumatic system is preferred as the actuator of the device. The force of the actuator is controlled by regulating air pressure in both chambers of the cylinder. However, to improve …

Design, Fabrication And Analysis Of An Auxiliary Power Unit On A Heavy-Duty Truck To Power The Hvac Systems Of The Truck During Driver Off-Duty Conditions, Rohan Milind Kalurkar

Dissertations, Master's Theses and Master's Reports

Currently, one of the biggest challenges the world is facing is energy insufficiency. One of the contributors to energy consumption in United States are the idling semi-trailer trucks. In May 2001, President Bush issued The National Energy Policy in which he directed The Environmental Protection Agency (EPA) and Department of Transportation (DOT) to reduce the idling of trucks. This was done in order to reduce energy consumption by lowering fuel consumption and emissions coming out of semi-trailer trucks in the United States of America.

This project deals with the efforts of installing an Auxiliary Power Unit (APU) as a device …

Design And Fabrication Of A Suspension Rig, Abhijith Geo Philip

Dissertations, Master's Theses and Master's Reports

Owing to its placement under the vehicle body, the suspension system is one of the parts of the vehicle which are difficult to comprehend completely, albeit being a vital component. For demonstrating the working of a suspension system, a physical model in which one can actually see the movement of all the components would be a great tool. A Mustang II independent front suspension system was purchased from Heidts Engineering Performance and a rig that can emulate some of the real world situations of vehicle suspension action was designed and fabricated. All the components are accessible and conditions like bounce, …

Energy Resources Use Metrics, Rahul Y. Nehete

Theses and Dissertations--Mechanical Engineering

Energy resources use has been considered as a key component of sustainable development. Data related to global, regional, state, sector, industry and process demonstrate that a significant reduction of energy resources for a given production rate in manufacturing processes requires an introduction of transformational technologies at the process level, propagating the impact to higher scales, leading not just to a gradual improvement of traditional technologies but to more sustainable development.

The study offers two approaches to the formulation of the limits of energy use in the context of sustainable development. The first is to construct a map of key selected …

Parametric Investigations Into Internal Surface Modification Of Brass Tubes With Alternating Magnetic Field, Harish Kumar, Sehijpal Singh, Anil K. Srivastava

Manufacturing & Industrial Engineering Faculty Publications and Presentations

The final finish operations have great significance in an overall manufacturing cycle of a product. The surface finishing and modification of surfaces have been the vital requirements of most of the products. The processes like shot peening, shot blasting, abrasive finishing and super finishing are being largely employed for such requirements. While final finishing of flat and outside surfaces are relatively easy and well established, the internal surfaces such as those of pipes is not so simple. In this paper, the application of low frequency alternative magnetic field has been explored for imparting surface modification including surface on the internal …

Period Batch Control - A Production Planning System Applied To Virtual Manufacturing Cells, Z. Tesic, B. Stevanaov, V. Jovanovic, M. Tomic, C. Kafol

Engineering Technology Faculty Publications

Period Batch Control (PBC) system has been known for its implementation with the classical group technology (GT) cells, and it has been known for its simplicity. The main production planning decisions concern the choice of the period length and the stage number and contents. Also, in order to better integrate the production planning with the application of GT cells at the shop floor, the concept of virtual manufacturing cells has been applied. Since virtual cells configurations are changing periodically, a model for implementing the PBC system into virtual manufacturing cells environment is developed. The model enables alignment of the PBC …

Fatigue Properties Of Magnetorheological Elastomers And The Design Of Interfacial Layers To Improve Fatigue Life., Yanfen Zhou

Doctoral

The primary aim of this PhD programme was to understand the fatigue behaviour of magnetorheological elastomers (MREs) and provide a reliable fatigue life predictor for this class of materials. To realise this aim required the study of the dynamic behaviour of MREs using the equi-biaxial bubble inflation test method. Isotropic and anisotropic MREs were fabricated from silicone rubber (SR) filled with soft carbonyl iron (CI) particles. The equi-biaxial fatigue behaviour of these samples was determined using a bubble inflation method. Wohler (S-N) curves for both isotropic and anisotropic MREs were produced by subjecting the compounds to cycling over a range …

Process Improvement By Lean Thinking In Trucking Industry, Abhiram Reddy Ramasahayam

All Graduate Theses, Dissertations, and Other Capstone Projects

Manufacturing industries with complex production systems are struggling with designing optimal process to increase throughput. Companies will require high amount of labor and process improvement resources to sustain growth and delivery quality products to its customers. A chain of value added activities when designed and deployed with help of lean based methodologies can create high efficiency process. In this paper we have studies and implemented value added process based on the lean manufacturing methodologies which was adapted on the shop floor.

In many traditional truck body production industries have facing many problems like low production rate, big lead times, material …

The University Of Akron Human Powered Vehicle Team, Maria E. Rizzo, Andrew J. Derhammer, Christopher M. Trowbridge, Timothy M. Nutt, Joseph R. Boyd, Jeremy W. Marcum, Jonathan E. Adams, Donald G. Haiss, Julia Wood, Brian D. Goshia, Scott T. Fagan, Joshua D. Everhard, Rebecca L. Slivka

Williams Honors College, Honors Research Projects

The University of Akron Human Powered Vehicle Team’s 2016 vehicle, Klokan, was designed, manufactured and tested with safety, reliability, performance and ease of use in mind. The vehicle is a fully faired tadpole trike with a lightweight aluminum frame constructed from 6061-T6 tubing having a total weight of 8.9 lbs. To complement the lightweight frame, the fairing is constructed from polycarbonate, PETG and carbon fiber strips which combine into a lightweight, easy to manufacture weather barrier and aerodynamic structure. Klokan was designed to be a safe and efficient mode of everyday transportation which ensures that riders are sufficiently protected by …

Enhancing Project Management With Lean World Class Manufacturing In Construction, Jacob Randles

Electronic Theses and Dissertations

In construction, the goal of commercial projects is to turn a profit. This is achieved by minimizing inputs and maximizing outputs while building a product that meets the customer’s perception of value. Value is determined through pre-negotiated specifications, plans, and material quality. Even in U.S. military construction, the unit executing the construction wants to complete the task on time and on budget, which can be difficult to do. Studies on project completion showcase a surprisingly high rate of failure in reaching the aforementioned “on time, on budget” goal. It is important to understand the nuances and details of U.S. Army …