Engineering Commons^™

Experimental And Numerical Studies On Laser Hot Wire Cladding By A High-Power Direct Diode Laser, Mingpu Yao

Mechanical Engineering Research Theses and Dissertations

Laser hot wire cladding is an advanced surface modification technology. It has been extensively growing during the last decades due to its high deposition rate, good metallurgical bonding between the substrate and clad layer, low dilution ratio, and small heat-affected zone. There are many kinds of lasers widely used in the laser cladding process. The high-power direct diode laser is widely welcomed because of its high energy efficiency, high electro-optic conversion efficiency, low cost, and high reliability. A rectangular-shaped direct diode laser beam combined with hot wire feeding can achieve a lower dilution depth with a uniform fusion line compared …

Baby Soothing Device, Grace Kalene Mekrut, Matteo Gozzini, Miles Angel Ibarra, Christian Joel Roberts

Mechanical Engineering

This document is the official final design review for the Baby Soothing Device. This product is intended to help families sleep throughout the night by allowing a baby to be soothed back to sleep without constant and direct parental interaction. It is maintained by Mechanical Engineering students at California Polytechnic State University, San Luis Obispo for Dustin Yoder, the project sponsor. The purpose of this document is to present the design process from ideation to finished design in great enough detail that its manufacturing procedure may be replicated if desired. This document further explains all the research, testing, and benchmarks …

Novelty Ice Cream Assembly Prototype, Mason Sylvester, Logan Williamson, Alvaro Martinez, Adin Gilman-Cohen

Mechanical Engineering

Cool Beans USA is a novelty ice cream startup company founded by Keith Zachow. In the winter of 2022, our team began working with Mr. Zachow to develop a machine to automate parts of the production process for his product. This product consists of two hemispherical ice-cream cone shell halves filled with soft serve ice cream and pressed together. The assembled pods are around the size and shape of a small walnut and are intended to be sold in stores as a frozen finger food. At the time of project inception, this product was in its early stages and was …

Repeatability And Reproducibility Analyses For Structured Light Scanning, Leah Jacobs

Masters Theses

Structured light scanning is used to create a digital twin of a manufactured part. Features can be extracted from this digital twin to determine if the part meets the designer’s intent and required tolerances. This paper describes a repeatability and reproducibility study for a selected structured light scanning system and measurement artifact.

Path Planning For Additive Manufacturing Of Wire Arc Additive Manufacturing And Blue Light Fringe Projection Scanning, Tiffany Patricia Quigley

Masters Theses

Current methods of manufacturing large scale parts can take up to six months to generate the objective product. The objective of the wire arc additive manufacturing (WAAM) hybrid cell is to significantly reduce lead time associated with large scale parts. The WAAM process utilizes a 6 degree-of-freedom (DOF) robot manipulator in addition to a 2 DOF part positioner. 5 degrees of freedom are necessary for an effective WAAM process, leaving 3 DOF as redundant in this cell. This thesis serves to prove successful implementation of redundant kinematics on a WAAM robotic system. This is accomplished by maintaining a gravity aligned …

Optimized 3d-Printing Of Carbon Fiber-Reinforced Polyether-Ether-Ketone (Cfr-Peek) For Use In Overmolded Lattice Composite, Ryan C. Ogle

Masters Theses

Current orthopedic implants are overwhelmingly composed from metallic materials. These implants show superior mechanical properties, but this can additionally result in stress shielding due to a modulus mismatch between the bone tissue and implanted device. Polymeric implants reduce this stress shielding effect but have much lower mechanical properties, limiting their use. Polylactic acid (PLA) is a widely used biodegradable thermoplastic polymer, however, its use has been limited by the polymer’s mechanical properties and rapid loss of strength during degradation in vivo. Polyether-ether-ketone (PEEK) is another common biocompatible polymer , with chemical and mechanical properties which make it a popular alternative …

Multiple Objective Function Optimization And Trade Space Analysis, Yifan Xu

All Theses

Optimization can assist in obtaining the best possible solution to a design problem by varying related variables under given constraints. It can be applied in many practical applications, including engineering, during the design process. The design time can be further reduced by the application of automated optimization methods. Since the required resource and desired benefit can be translated to a function of variables, optimization can be viewed as the process of finding the variable values to reach the function maxima or minima. A Multiple Objective Optimization (MOO) problem is when there is more than one desired function that needs to …

Fabrication Of Solar Absorber Tube With Internal Fin Structure With In718 And Effect Of Boron With In718 For Solar Absorber Tube Using Selective Laser Melting 3d Printing Technology, Naznin Nuria Afrin

Theses and Dissertations

This research aimed to fabricate Solar Absorber Tubes for Solar-Thermal Power Plant with internal fin structures using Selective Laser Melting (SLM) technology. In this study, we investigated the effect of B with IN718 in 3D printing using SLM for solar absorber tubes. The objective was to study the material-process-properties relationship with goal to identify and validate the optimal parameters for the SLM process. Material selected for this study was IN718 with 0.5% and 1% B particle mixed using a V-shape mixing machine. The flowability test was conducted using the Angle of Repose (AOR) method. 3D printed samples …

Callaway Measurement Device, Andre S. Fisher, Roman Hays, Blake Sousa, Grant Gabrielson

Mechanical Engineering

The purpose of this document is to illustrate the Callaway Measurement Device senior project from start to finish. The challenge given to the team was to update and improve a gauge used by Callaway employees to measure the loft, lie, and face angle of their full spectrum of golf clubs. Once the team understood how the pre-existing gauge operates, the team conducted background research into other technologies that could improve the gauge. The team decided to digitalize the device amongst other tweaks to reduce error. Because the CAD files were not available for the pre-existing device, the team began reverse …

Rotating Backing Brush, Caleb Savard, David Dalal, Max Allred, Mathis Weyrich

Mechanical Engineering

In the final steps of GAF’s shingle production process, small asphalt particles called fines are applied. Some fines adhere well to the shingle sheet, while others temporarily stick only to fall off the sheet further down the manufacturing line. As a result, the shingle plant floor is covered in fines that have fallen due to vibrations and gravity. The technicians and engineers at GAF want a cleaner working environment and to potentially reuse the loose fines. We are a senior project team that solved this problem by designing a system to remove and collect loose fines. In this document, the …

Novel Hitch Cargo Cart, Cesilio Sanchez Ramirez, Lance Haidet, Richard Lontoc, Tyler Selinka

Mechanical Engineering

This document presents the engineering design process used to develop, manufacture, and test a new and improved iteration of a hitch cart prototype. This process was performed by a team of four mechanical engineering seniors as part of California Polytechnic State University, San Luis Obispo’s senior design pathway. The goal of this project was to develop a sturdy and reliable iteration of our sponsor’s hitch cart prototype, that integrated the functionality of a vehicle hitch cargo platform and that of a height adjustable cargo cart into a single streamlined and easy to use product. This design could be used by …

The Deflection And Heat Transfer Analysis Of Injection Mold Cavity With Sla Cooling Channel Insert, Olumide Temidayo Aladesiun

Theses and Dissertations

Fast cooling in injection molding is the critical in the process economy. Among many different cooling channel designs available, conformal cooling offers the best and the most efficient cooling. However, limited awareness, accessibility, complexity, cost, knowledge, and experience limit the use of conformal cooling channels to be used into the mold in a molding process.

Typically, SLM(Selective Laser Melting) method is used to create cavity inserts with conformal cooling channels, however, due to the difficulties listed above, applications of conformal cooling channels are very limited. For an inexpensive alternative SLA (Stereolithography Apparatus) can print cavity inserts with conformal cooling channels. …

Ultrafast Laser Direct Writing Of Conductive Patterns On Modified Polyimide Film For Flexible Electronic Applications, Ishrat Jahan Biswas

Theses and Dissertations

Conductive patterns can be printed on a flexible polymer substrate using the direct laser writing (DLW) method. In order to write conductive circuits in such polymer using a laser, polyimide (PI) is a desirable material choice due to its electrical, chemical, and mechanical properties. Electrically non-conductive PI has shown great potential for flexible printed electronics as LDW enables selective carbonization in the bulk of such material leading to the formation of conductive lines. The technique is shown to be a rapid and minimal cost method for printing electrodes to nanoscale devices. However, investigations in this field show several limitations to …

A Study Of The Surface Properties Of Additive Manufactured Inconel 718 After Laser Surface Treatment And Cnc Grinding, Sampson K. Canacoo

Theses and Dissertations

This study investigated the surface properties of additive manufactured Inconel 718 produced through selective laser melting, and the effects of laser ablation and CNC grinding on the surface finish. The objectives were to investigate the effects of the various parameters of laser ablation and CNC grinding on the Inconel 718 surface. The parameters used for the laser experiments were pulse energy (4, 20, and 30 µJ), scanning speed (5, 10, and 15 mm/s), and hatch distance (10, 30, and 50 µm). For the grinding experiments, the wheel speed was kept constant at 20.3 m/sec, however, two different workpiece speed (8.6 …

A Numerical Simulation Of The Powder Bed Additive Manufacturing Process With Molecular Dynamics Simulation, Yeasir Mohammad Akib

Theses and Dissertations

Many manufacturing industries utilize powder bed fusion (PBF) since it can produce microscale precision 3D parts. During PBF, powder particles are selectively fused layer by layer using thermal energy. The build quality in the PBF process relies heavily on powder bed properties and thermal energy deposition. Powder flowability, spreadability, and packing fraction are some of the insightful factors that determine the quality of the powder bed. In this study, a two-dimensional powder bed is developed using the LAMMPS package. A cloud-based pouring of powders with varying volumes and initialization is adopted for the work. A blade-type and circular recoater is …

Investigation Of Process Parameters To Fabricate Refractory Medium-Entropy Alloy By Selective Laser Melting Process, Abdullah Al Masum Jabir

Theses and Dissertations

This thesis proposal investigates the synthesis of TiWMo refractory medium entropy alloy (RMEA) by selective laser melting process from elemental powder. Steel, titanium and tungsten substrates were used to study the impact on the formation of TiWMo RMEA. Different process parameters were applied to investigate the effects on melting, diffusion and formation of RMEA. The microstructure of TiWMo and elemental distribution were observed by scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). SEM analysis revealed that with higher energy density the pores and microcracks were improved. EDS data validated the composition is homogenized and stable after few layers …

Femtosecond Pulse Filamentation In Dielectric Media Toward Photonics Sensor Fabrication, Anitha Narayanan

Theses and Dissertations

Through pulse filamentation, femtosecond laser pulses have been utilized to modify the refractive indices of dielectric materials such as glass, A-plane sapphire crystal, and Cplane sapphire crystal. The 10x Infinity Corrected Lens was used, and the focusing condition was tuned as being the same and fixed to both glass and sapphire crystals. First, 8uJ of laser energy was optimized to produce controlled pulse filamentation voids in the glass. The laser intensity was then optimized to 2-3.5 uJ, 1.5 uJ, & 2.5 uJ, respectively, for the controlled pulse filamentation in A and C plane sapphire crystals. Due to the different crystal …

Feasibility Analysis Of Embedding Optical Fiber Sensor Into Additively Manufactured Part, Mahmudul Hasan Porag

Theses and Dissertations

The research tried to examine the viability of the embedment of optical fiber sensors in Additively built components, packaging the sensors within the components, and characterizing the sensors for sensing a specified measurement. Optical fiber sensors are popular due to their small size, resilience against electromagnetic radiation, and reliability in potentially dangerous conditions. Embedding fibers inside a product allows for the monitoring of critical areas, allowing for preemptive action in the case of a breakdown. Coupons of Inconel 718 were made using laser powder-bed fusion (LPBF), with the fabrication settings tuned to determine whether such a development was possible. After …

Characterization Of Materials Properties In Additively Manufactured Aisi-420 Martensitic Steel Deposited By Laser Engineered Net Shaping, Md Mehadi Hassan

Nanoscience and Microsystems ETDs

Metal additive manufacturing (AM) is a disruptive technology enabling the fabrication of complex and near-net-shaped parts by adding material layer-wise. It offers reduced lead production time. AM processes are finding applications in many industrial sectors such as aerospace, automotive, biomedical, and mold tooling. Despite the tremendous advantages of AM, some challenges still prevent this technology's adoption in high-standard applications. Anisotropy and inhomogeneity in the mechanical properties of the as-built parts and the existence of pores and lack-of-fusion defects are considered the main issues in directed energy deposition (L-DED) parts. Laser-engineered net shaping LENS® offers excellent possibilities to fabricate metal tools …

Biomass Characterization And Insulation Optimization Studies, Hussein Awad Kurdi Saad

Doctoral Dissertations and Master's Theses

This study indicates how biomass materials can be effectively used as naturally sustainable alternatives to insulation materials. Barley grains and oak leaves, straw, and jute are collected, and crushed into powders/ chopped pieces. The physical characteristics are measured to characterize each powder. The biomass powder reinforced composites are manufactured in varying weight ratios. The density and thermal conductivity of composite materials are measured. The properties of composites compared to those of commercial insulation materials are found to be close to them. Furthermore, genetic algorithms (GA) can be used to achieve multi-objective optimization entailing maximizing insulation (minimizing heat transfer) and simultaneously …

A Machine Learning Approach To Robotic Additive Manufacturing Of Uv-Curable Polymers Using Direct Ink Writing, Luis A. Velazquez

LSU Master's Theses

This thesis presents the design and implementation of a robotic additive manufacturing system that uses ultraviolet (UV)-curable thermoset polymers. Its design considers future applications involving free-standing 3D printing by means of partial UV curing and the fabrication of samples that are reinforced with fillers or fibers to manufacture complex-shape objects.

The proposed setup integrates a custom-built extruder with a UR5e collaborative manipulator. The capabilities of the system were demonstrated using Anycubic resin formulations containing fumed silica (FS) at varying weight fractions from 2.8 to 8 wt%. To fully cure the specimens after fabrication, a UV chamber was used. Then, measurements …

Hypoxic Incubation Chamber, Simone Lisette Helfrich, Makenzie Nicole Jones

Biomedical Engineering: Graduate Reports and Projects

This paper describes the design, manufacturing, and testing of a novel controllable hypoxic incubator with fully functional oxygen gas control and temperature control in a humid environment. On the current market, a majority of the few hypoxic incubators use pre-mixed gas that does not offer precise control over gas concentration. The objective for this project was to create a chamber that allows the user to set the O2 concentration to varying set points of % O2 while maintaining the chamber at a constant body temperature, CO2 level, humidity, and sterility. To start the project, multiple concepts were developed for the …

Hypoxic Incubation Chamber, Simone Lisette Helfrich, Makenzie Nicole Jones

Master's Theses

This paper describes the design, manufacturing, and testing of a novel controllable hypoxic incubator with fully functional oxygen gas control and temperature control in a humid environment. On the current market, a majority of the few hypoxic incubators use pre-mixed gas that does not offer precise control over gas concentration. The objective for this project was to create a chamber that allows the user to set the O2 concentration to varying set points of % O2 while maintaining the chamber at a constant body temperature, CO2 level, humidity, and sterility. To start the project, multiple concepts were developed for the …

A Benchtop Robotic Automation Approach For Manufacturing Prefilled Syringes, Yehua Zhong

All Theses

Automation and robotics have become a staple in the biological manufacturing sector due to their ability to efficiently work without operator inputs, with a high degree of accuracy and repeatability. Industrial robotic arms, in particular, present themselves as valuable tools for biological manufacturing scenarios that require customized solutions due to their ease of programming and flexibility. The traditional hospital-focused healthcare system was organically developed to address acute conditions, however, in recent years, due to the unprecedented occurrence of emergencies happening more frequently, fast and efficient drug production becomes important [17]. This thesis represents the use of a benchtop robot and …

Additive Manufacturing Of Molybdenum For High Temperature Structural Applications, Megan L. Bustin

Theses and Dissertations

This research considered additive manufactured (AM) molybdenum (Mo) and the effect of three variables on microstructure, mechanical properties, and the relationship between the two. Test temperature, laser speed, and shield gas or build atmosphere were varied, and samples tested and analyzed using a three-point bending test, chemical composition, and optical and scanning electron microscopy. The relationship among variables and results using a Design of Experiments was limited compared to the inclusion of every tested sample. Most effects were expected: samples tested at room temperature were brittle without statistical significance; increasing laser speed resulted in decreased ductility and strain, smaller grain …

Additively Manufactured Polymer And Metal Lattice Structures With Eulerian Path, Adeeb Ibne Alam

Electronic Theses and Dissertations

Lattice structure manufacturing with polymers and metals can benefit from the use of Eulerian paths. In this research, two types of lattice fabrication methods are studied where the Eulerian path can be applicable. Polymer lattice is improved by using a new assembly design, while a new way of metal lattice fabrication is discussed.

For the fused filament fabrication process, a new interlocking design and assemble-based lattice structure building approach is investigated by increasing continuity in layers and avoiding support structures. To minimize contour plurality, Eulerian paths between the edges were enforced. Two configurations in the form of cubic and octet …

Aluminum-Based Material Fabrication By Friction Stir Processing: Microstructural Evolution And Mechanical Properties, Suhong Zhang

Doctoral Dissertations

Friction stir processing (FSP) is an energy efficient solid-state material processing technique for microstructure modification of commercial high-strength Al alloys. Many variant techniques were developed in recent years that enabled light-weight and high-strength structure fabrication. Identifying relationship among process conditions, microstructures, and mechanical properties is of critical importance to facilitate the practical implementation of these new techniques. The research in the dissertation focusses on developing two main techniques of the FSP: a) friction stir back extrusion (FSBE) of 6063 aluminum alloy for tube making and b) FSP of 7075 aluminum alloy from powder feedstock. FSBE fabricated Al 6063 alloy tubes …

Additive Metal Deposition Feedback Optimization For The 3d Hybrid Metal Printer, Andrew James Wyman

Dissertations

In the additive manufacturing realm, explicitly the direct energy deposition method, there continues to be numerous advancements along with advantages to control print quality of the component and the ability to apply the successful repetition of metallic layers consecutively. Metal additive printed components have the capacity to directly use the component for the desired application or intended purpose from which the three-dimensional model was created. In contrast, plastic printers that produce components that would not hold to the physical conditions required such as a metallic component could withstand.

Research exertions were focused on improving the present Western Michigan University patented …

Additive Manufacturing Of Aluminum Alloy By Metal Fused Filament Fabrication (Mf3)., Luke J. Malone

Electronic Theses and Dissertations

This research studies metal-fused filament fabrication (MF3) for manufacturing aluminum alloy parts. An aluminum alloy powder-based feedstock with a polymer-binder system was extruded via capillary rheometry to form a filament. The filament was used to print green parts that were involved in a two-step debinding process combining solvent and thermal extraction of the polymer binder, then sintered in a partial vacuum. Resulting grain structure, sintered density, and mechanical properties will be characterized and compared to metal injection molded (MIM) specimens. The main objective is to gain an understanding of the MF3 process characteristics and the ensuing material properties and microstructure …

A Modification To The Skiving Process For The Manufacture Of Offset Geometry Strip-Fin Heat Sinks, Daniel Luberda

McKelvey School of Engineering Theses & Dissertations

High-powered electronics are extremely prevalent, and a vast majority of these devices use some form of heat sinks as either an active or passive cooling device. Although two-phase cooling technology has rapidly advanced to accommodate increasing heat loads on modern electronics, the added costs and complication inherent in two-phase cooling solutions makes effective air-cooled heat sinks potentially valuable.

A more effective heat sink can occupy a smaller footprint to dissipate the same heat flux, meaning material and packaging costs can be reduced. Aluminum heat sinks are produced through a variety of manufacturing processes, including machining, bonding, extrusion, casting, forging, 3D …