Manufacturing Commons^™

Optimal Rastering Orientation In Freeform Extrusion Fabrication Processes, Amir Ghazanfari, Wenbin Li, Ming-Chuan Leu, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Many researchers have tried to optimize the build direction of additively manufactured parts to minimize the vertical staircase effect. However, the horizontal staircase effect should also be considered when fully dense parts are to be fabricated. In this paper, part inaccuracy due to the horizontal staircase effect is considered in order to determine the optimal rastering orientation in building the part. An algorithm is developed to estimate this inaccuracy and a technique is proposed to minimize it. The effect of rastering orientation on staircase errors is examined, and the particle swarm optimization method is used to determine the optimum rastering …

Direct Laser Deposition Of Ti-6al-4v From Elemental Powder Blends, Lei Yan, Xueyang Chen, Wei Li, Frank W. Liou, Joseph William Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A thin-wall structure composed of Ti-6Al-4V has been deposited using direct laser deposition (DLD) from blended Ti, Al, and V elemental powders. The microstructure and composition distribution along the build height direction were intensively investigated using optical microscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS), and Vickers hardness testing. The microstructures of the as-deposited Ti-xAl-yV were studied using EDS to determine appropriate weight percentage for Al and V in the blended powders before mixing. The effects of laser power and laser transverse speed on the microstructure were investigated and optimized laser processing parameters were concluded.

Modeling Of Powder Bed Processing -- A Review, Aaron Flood, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Many models have been developed to model powder beds and these methods can be implemented to model a powder bed for Selective Laser Sintering, Selective Laser Melting and any other technique of additive manufacturing which uses powder beds. Two of the main systems are the Discrete Element Method (DEM) and the Geometric Method. The purpose of this paper is to analyze each of the methods. It will first highlight how each of the models creates the powder bed. The next aspect reviewed is the computational time and its causes. And lastly, each of the methods will be examined for their …

Solid Freeform Fabrication Of Transparent Fused Quartz Using A Filament Fed Process, J. Luo, L. J. Gilbert, C. Qu, B. Morrow, Douglas A. Bristow, Robert G. Landers, J. Goldstein, A. Urbas, Edward C. Kinzel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Glass is a critical material for many scientific and engineering applications including optics, communications, electronics, and hermetic seals. Despite this technological relevance, there has been minimal research toward Additive Manufacturing (AM) of glass, particularly optically transparent glass. Additive Manufacturing of transparent glass offers potential advantages for lower processing costs for small production volumes, increased design freedom, and the ability to locally vary the optical properties of the part. Compared to common soda lime glass, fused quartz is better for AM since it has lower thermal expansion and higher index homogeneity. This paper presents a study of additive manufacturing of transparent …

Dc-Gain Layer-To-Layer Stability Criterion In Laser Metal Deposition Processes, Patrick M. Sammons, Douglas A. Bristow, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In Laser Metal Deposition (LMD), a blown powder metal additive manufacturing process, functional metal parts are fabricated in a layer-by-layer fashion. In addition to the in-layer dynamics, which describe how the process evolves within a given layer, the additive-fabrication property of LMD creates a second set of dynamics which describe how the process evolves from layer-to-layer. While these dynamics, termed layer-to-layer dynamics, are coupled with both the in-layer dynamics and the process operating conditions, they are not widely considered in the modeling, process planning, or process control of LMD operations. Because of this, seemingly valid choices for process parameters can …

Performance Metric For Powder Feeder Systems In Additive Manufacturing, Venkata Sivaram Bitragunta, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In blown powder Direct Metal Deposition (DMD) process, parts are built by adding metal powder on the melt pool created by the laser system. At low feed rates powder feeder systems have perturbations. The study focused on relationship between the perturbation frequencies by inherent powder feeder designs and its impact on deposition quality. Performance metric determine the relation between perturbations in the powder flow and quality of the deposit. To determine performance metric, various powder feeder designs were analyzed. Perturbation frequencies were introduced to the disk feeder design. The quality of the deposit was determined by the surface roughness of …

Parameter Determination And Experimental Validation Of A Wire Feed Additive Manufacturing Model, Kannan Suresh Kumar, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser metal deposition with wire feed is one of the additive manufacturing methods with great scope and robustness. Process parameters plays an important role in controlling the process and obtaining an ideal manufactured part. Simulations tools are highly essential in determining the ideal parameters and melt pool conditions. The current work is a transient 3D model of wire feed additive manufacturing which realizes the heat transfer and fluid flow behavior of the process with varying laser power and power density. The model was programmed in Python and a 1 KW Gaussian beam fiber laser was used to conduct experiments. The …

Depth Of Cut Monitoring For Hybrid Manufacturing Using Acoustic Emission Sensor, Haythem Gaja, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser Metal Deposition LMD is a hybrid manufacturing process consist of a laser deposition system combined with a 5-axis CNC milling system. During laser deposition many parameters and their interaction affect the dimensional accuracy of the part produced, powder flow rate, laser power and travel speed are some of these parameters. Sensing the acoustic emission during milling marching gives feedback information regarding depth of metal being cut subsequent part dimensions, if an error in dimensions is found certain actions, such as remaching, close loop control, or laser remelting can be carried out to correct it. Thus a reliable hybrid manufacturing …

Methods Of Extrusion On Demand For High Solids Loading Ceramic Paste In Freeform Extrusion Fabrication, Wenbin Li, Amir Ghazanfari, Ming-Chuan Leu, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fabrication of highly dense parts with complex geometry by paste-extrusion-based solid freeform fabrication processes requires a precise control of the extrusion flow rate to dispense material on demand, which is often referred as Extrusion-On-Demand (EOD). The extrusion process for aqueous ceramic pastes is complex and difficult to control due to their non-Newtonian behavior, compressibility and inhomogeneity. In this study, three methods of EOD (based on ram extruder, needle valve, and auger valve) are introduced and investigated for the extrusion of high solids loading (i.e., > 50%, volumetric) aqueous alumina paste. Optimal extrusion process parameters for these methods are determined through printing …

Planning Freeform Extrusion Fabrication Processes With Consideration Of Horizontal Staircase Effect, Amir Ghazanfari, Wenbin Li, Ming-Chuan Leu, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An algorithm has been developed to estimate the “horizontal” staircase effect and a technique is proposed to reduce this type of geometrical error for freeform extrusion fabrication processes of 3D “solid” parts. The adaptive rastering technique, proposed in this paper, analyzes the geometry of each layer and changes the width of each line of the raster adaptively in order to reduce the staircase error and increase the productivity simultaneously. For each line, the maximum width that results in a staircase error smaller than a predefined threshold is determined for decreasing the fabrication time or increasing the dimensional accuracy, or both. …

A Framework For Large Scale Fused Pellet Modeling (Fpm) By An Industry Robot, Zhiyuan Wang, Renwei Liu, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fused pellet modeling (FPM) is an important method in additive manufacturing technology, where granular material is used instead of filaments. In FPM, prototypes are constructed by the sequential deposition of material layers. As the size of the part increases, the problem of long build times and part deformation becomes critical. In this paper, methods for eliminating the void density during deposition and accuracy control principles for large scale FPM processes are studied. By analyzing the ab initio principles of this process, a mini extruder with variable pitch and progressive diameter screw for the large scale fused deposition is proposed. Based …

Securemems: Selective Deposition Of Energetic Materials, Trevor J. Fleck, Josiah R. Thomas, Lillian F. Miles, Allison K. Murray, Zane A. Roberts, Raghav Ramachandran, I Emre Gunduz, Steven F. Son, George T. Chiu, Jeffrey F. Rhoads

The Summer Undergraduate Research Fellowship (SURF) Symposium

There exists a pressing operational need to secure and control access to high-valued electromechanical systems, and in some cases render them inoperable. Developing a reliable method for depositing energetic materials will allow for the near-seamless integration of electromechanical systems and energetic material, and, in turn, provide the pathway for security and selective destruction that is needed. In this work, piezoelectric inkjet printing was used to selectively deposit energetic materials. Nanothermites, comprising of nanoscale aluminum and nanoscale copper oxide suspended in dimethyl-formamide (DMF), were printed onto silicon wafers, which enabled both thermal and thrust measurements of the decomposing energetic material. Various …

Integrating Systems For Liquid/Substrate Characterization And Functional Printing, Jianyi Du, J. William Boley, Rebecca K. Kramer

The Summer Undergraduate Research Fellowship (SURF) Symposium

Gallium-Indium alloys are recently applied in fabricating soft devices, such as stretchable sensors, electric circuits, micro pumps and optics. Its printability demonstrates the possibility for a wide extension of the application. Current fabrication methods are inefficient when printing is most handled manually, and are highly dependent on material properties. There is need for a fast way to characterize material properties, and to functionally print the given shape on the substrate. This paper presents the construction of an efficiently integrated system with optical imaging and functional printing for Gallium-Indium alloys. The imaging section allows for characterization of material properties to fast …

Investigation Of Slective Laser Melting Of Mecanically Alloyed Metastable Al5fe2 Powder, Hugo Montiel

Theses and Dissertations - UTB/UTPA

Selective Laser Melting (SLM), an Additive Manufacturing (AM) technology, enables the production of complex structured metal products. Aluminum alloys are used in SLM as high-strength lightweight materials for weight reduction in structural components. Previous investigations report high laser powers (300 W) and slow scanning speeds (500 mm/s) to process aluminum alloys under SLM. This research investigates the SLM processing of Al-Fe alloy by utilizing metastable Al5Fe2 powder system produced by mechanical alloying. Metastable systems are thermodynamically activated with internal energy that can generate an energy shortcut when processing under SLM. The optimum laser power, scan speeds and scan distances were …

A Study Of The Selective Laser Alloying Of Elemental Titanium And Boron Powder, Yingbin Hu

Theses and Dissertations - UTB/UTPA

To better understand the selective laser alloying process of elemental titanium and boron powder, theoretic models are created which takes material related, reaction related, laser related, and other affecting factors into consideration. These models do help interpret the corresponding experiment results. In turn, the related experiment results validate the theoretic models created. In practice, the experiments with two different molar ratios of 1:2 and 4:1 between titanium and boron are carried out. The huge amount of energy released because of reaction between titanium and boron during laser irradiation makes it hard to understand and control the alloying process. At the …

Increasing The Independence Of Children With Spina Bifida Through The Designing And Building Of A Mechanical Aide, Andrew Duffek, Robert Brent, Michael Hamada, Melissa Rodriguez

Industrial and Manufacturing Engineering

In order to assist Silas Hopper, a child with spina bifida, with getting into his wheelchair independently when being on the ground, the senior project team set out to construct a device that would fulfill that purpose. They did this through coming up with a strict definition of the problem to be solved, designing a number of potential solutions for the problem, prototyping to determine the feasibility of the solutions, making design modifications after testing the prototype, and building the final device.

The end product was a device that was able to operate mechanically, with a design that considered safety …

Small Scale Erp Engine Design, Colyn Muir Dickson, Matthew Wade Haymond

Industrial and Manufacturing Engineering

This project set out to create a 1) low-cost, 2) dynamic, and 3) user-friendly small scale ERP software tool. These three key attributes position this product against complex and expensive systems such as SAP or Oracle. While the product still retains the dynamic and financial capabilities any good ERP system should have, the biggest value proposition is its simple and user-friendly interface. The software has a dual product-market fit: for small businesses as a low-cost planning tool, and for universities as a teaching tool. In the design phase, the team kept a primary focus on ergonomic software development while maintaining …

Tesla Motors Quality Engineering Application And Implementation, Nick Kwan

Industrial and Manufacturing Engineering

Tesla Motors, in Winter 2013 during the author’s coop,had a variety of potential improvement areas regarding their quality engineering team. There were too many overall defects on the vehicles. Those defects were recognized as the cars were passing through inspection, coming off the line, as well as brought by customers to after-purchase service. One of the defects was the Charge-port Door Malfunction, in which the door of the Model S would not open on command. An additional defect was the Windshield Wiper Malfunction, in which the fluid was not hitting the car at the desired angle. Both of these defects …

Database Design For The Collection And Visualization Of Sustainabilty Data, Henry A. Kozlowski, Nikhila Perugupalli

Industrial and Manufacturing Engineering

The goal of the project was to create a database that would be a repository for the high volume of sustainability data Illumina would like to collect. To couple with the database the project team’s goal was to design a system for visualizing the data graphically. Illumina required a database system that would be user-friendly, easy to add, delete, and edit data inputs, as well as a program that would allow the user to easily sort and graph data. The intent of the graphical representation of the data is to publish the graphs in a monthly report that would be …

Industrial Engineering Consulting, Blake J. Ahrold, Torrey M. Plana

Industrial and Manufacturing Engineering

This paper documents the senior project of Blake Ahrold and Torrey Plana. This project was created to provide a solution to the problem of small to medium Sized enterprises (SMEs) being under represented by lean consulting companies. The project was at first intended to be a lean consulting startup and then pivoted to The Systems Optimization Club. A project charter, Gantt chart, and business model canvas were created for the startup and used as guidelines in the creation of the Systems Optimization club. The club is to be run like a lean consulting company. The club will provide teams of …