Manufacturing Commons^™

Effect Of Gold Content On The Reliability Of Snagcu Solder Joints, Jianbiao Pan, J. Silk, M. Powers, P. Hyland

Industrial and Manufacturing Engineering

Electroplated Ni/Au over Cu is a popular metallization for printed circuit board finish as well as for component leads, especially wire-bondable high-frequency packages, where the gold thickness requirement for wire bonding is high. The general understanding is that less than 3 wt% of Au is acceptable in SnPb solder joints. However, little is known about the effect of Au content on the reliability of SnAgCu solder joints. The purpose of this paper is to determine the acceptable level of Au in SAC305 solder joints. Three different package platforms with different Au thicknesses were assembled on boards with two different Au …

Novel Approaches To The Analysis Of Localised Stress Concentrations In Deformed Elastomers, John Mcnamara

Doctoral

The research described here is concerned with improving finite element analysis (FEA) of rubber components subjected to dynamic loading, particularly in respect of accurate modelling of stress softening using standard software codes and phenomenological material models. The research required the design and implementation of a user subroutine capable of inclusion in standard highly nonlinear codes. Experimental methods were employed to corroborate the FEA simulations and so validate the subroutine. This was also achieved using 3D image correlation photogrammetry (ICP) and other novel experimental procedures. From this experimentation and modelling, the results for different rubber specimens and load cases were presented. …

Effect Of Particle Size, Binder Content And Heat Treatment On Mechanical Properties Of 13-93 Bioactive Glass Scaffolds, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Particle size, binder content and the post-processing schedule are important parameters that affect the microstructure, and, hence, the mechanical properties of parts produced using the indirect selective laser sintering process. 13-93 bioactive glass, with mean particle sizes ranging from 10 μm to 44 μm, is mixed with different amounts of stearic acid binder to fabricate green scaffolds. Through the design of the post-processing schedule, the time required for postprocessing the green scaffolds is reduced from the initial 80 hrs to 12 hrs. The compressive strength varies from 41 MPa for a part with~60% porosity to 157 MPa for a part …

Freeze-Form Extrusion Fabrication Of Composite Structures, Ming-Chuan Leu, Lie Tang, Bradley K. Deuser, Robert G. Landers, Greg Hilmas, Shi C. Zhang, Jeremy Lee Watts

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Freeze-form Extrusion Fabrication (FEF) process capable of making three-dimensional (3D) parts and structures with graded composite materials is presented in this paper. The process development includes the design and manufacture of a gantry machine with a triple-extruder mechanism and the associated electronics hardware and computer software for fabricating functionally graded parts from multiple aqueous pastes. A rheological behavior study with Al₂O₃ paste is performed to identify an efficient binder for transforming the paste into a pseudoplastic with a high yield stress. A green part is first fabricated using the triple-extruder FEF machine in a layer-by-layer manner …

Bio-Inspired Design Of Bipolar Plate Flow Fields For Polymer Electrolyte Membrane Fuel Cells, Nannan Guo, Ming-Chuan Leu, Maoliang Wu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The flow field of a bipolar plate distributes hydrogen and oxygen for polymer electrolyte membrane (PEM) fuel cells and removes the produced water from the fuel cells. It greatly influences the performance of fuel cells, especially regarding reduction of mass transport loss. Flow fields with good gas distribution and water removal capabilities reduce the mass transport loss, thus allowing higher power density. Inspired by natural structures such as veins in tree leaves and blood vessels in lungs, which efficiently feed nutrition from one central source to large areas and are capable of removing undesirable by-products, a mathematic model has been …

Numerical Simulation Of Ram Extrusion Process For Ceramic Materials, Mingyang Li, Lie Tang, Fei Xue, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The freeze–form extrusion process for aqueous-based ceramic paste is complex due to the non-Newtonian behavior of the paste. In this paper the process is studied numerically using a developed mathematical model. The ceramic paste viscosity is characterized by the Herschel-Bulkley model. The relationship between plunger velocity and extrusion force is computed numerically. The influence of air, which is mixed with the paste during the loading process, is also examined. Due to the compressibility introduced by the trapped air, the plunger force dynamic response is typically dominated by a first order response. It is also shown that the extrusion plunger force …

A Strategy For Fabricating Complex Structures Via A Hybrid Manufacturing Process, Tarak A. Amine, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The purpose of this paper is to introduce a strategy for fabricating complex structures via a hybrid manufacturing process. The Laser Aided Manufacturing Process (LAMP) lab at Missouri S&T has developed a hybrid process combining both a direct metal deposition process and a five-axis CNC milling. Accessibility is a difficulty when finish machining internal features. The concept is to pause the deposition process to finish machine an internal feature while it is still visible is one possible solution to this issue. However, this must be done in a manner that will not be spoiled when the deposition process continues. This …

Octree Approach For Simulation Of Additive Manufacturing Toolpath, Ch. Sweta Dhaveji, Todd E. Sparks, Jianzhong Ruan, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Machine simulation is an effective way of checking additive manufacturing tool paths for both interferences and errors in part produced. This paper presents an algorithm to visually simulate a multi axis additive manufacturing system as it executes a process plan. Simulation results are intended to be used as a verification step before physically producing the part. Verification is particularly important for large builds of expensive materials. The algorithm uses an octree approach to efficiently model the deposition of part geometry and its changes. This paper discusses development of the simulation algorithm, including both the representation of the additive manufacturing machine …

Process Planning And Control For Functionally Graded Material Fabrication Using Freeze-Form Extrusion Fabrication, Brad Deuser, Lie Tang, Jeff Geldmeier, Robert G. Landers, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Using multiple materials in additive manufacturing technologies is critical for building parts with functionally gradient geometries. In order to achieve a desired material gradient, an advanced process planning and control system is required. This paper details the development of a process planning method and control system for functionally graded material fabrication using a triple extruder Freeze-form Extrusion Fabrication (FEF) system including motion code generation, extruder dynamic modeling and control, and composition gradient control. The effect that extruding multiple materials from a single orifice via static mixing has on the time delay of the resulting mixture is taken into account for …

Characterizing And Optimizing The Molten Salt Cleaning, Yangyang Long

Theses and Dissertations - UTB/UTPA

Molten salt cleaning is an important cleaning approach in remanufacturing which can remove a variety of contaminants from metal substrates with high efficiency. Facing the very limited research of this approach in literature, this thesis intends to characterize molten salt cleaning process and optimize its parameters when big parts with complicated shapes are cleaned. Based on the development of molten salt cleaning and studies on contaminations, two experiments are conducted. The first one investigates the influences of the hot salts on three metal substrates and shows the applicable of cleaning carbon steel and grey iron parts with molten salt. The …

Automating The Fret Slotting Process Using A Plc Controlled 1.5 Axis Mill, James Stratton

Purdue Polytechnic Masters Theses

Stratton, James A. M.S., Purdue University, August 2011. Automating the Fret Slotting Process Using a PLC Controlled 1.5 Axis CNC Mill. Major Professor: Richard Mark French.

Can automation assist small job shops and hobbyists in the production of stringed instruments? This research set out to answer the question using a quantitative approach to determine if an economical CNC machine could be produced in such a fashion as to seamlessly join the workshop as an affordable, yet precise instrument to aid in the production of stringed instruments. The key was to incorporate common industrial automation equipment into the operation of the …

The Transfer Of Laser-Machined Micro-Structured Patterns From Silicon To Polymethyl Methacrylate, Warren E. Withrow

Mechanical & Aerospace Engineering Theses & Dissertations

This research project's purpose was transferring a micro-scaled pattern from a silicon wafer to a polymethyl methacrylate (PMMA), or acrylic, substrate through light absorption generated heat. The secondary objective was to determine if the pattern on the silicon wafer could then be transferred to silica (i.e. a microscope glass slide) through light absorption generated heat. Once this pattern-transfer technique is developed for the micro scale, it could be instituted on the nano scale. The experiment was designed to find an alternate method to that currently being used to mass-produce compact discs (CDs). The most popular method employs a stamping process …

The Inside-Out Classroom: A Win-Win Strategy For Teaching With Technology, Daniel J. Waldorf, Lizabeth Schlemer

Industrial and Manufacturing Engineering

As costs of higher education soar and many universities face uncertain funding models, institutional pressures have increased to improve instructor efficiency. At the same time, U.S. industry leaders and leading educators have called for improvements in engineering education based on more interactive, hands-on student learning experiences. Although many efforts have been made to take advantage of technology to either improve student learning or to maintain student learning while increasing instructor efficiency, few approaches have been shown to improve both learning and efficiency. A teaching method is proposed to improve student learning and increase student satisfaction while also addressing the instructors’ …

Evolving A Summer Engineering Camp Through Assessment, Katherine Chen, Lizabeth Schlemer, Heather Scott Smith, Teana Fredeen

Industrial and Manufacturing Engineering

EPIC (Engineering Possibilities in College) is a one-week summer program for high school students (entering 9th-12th grades) to learn about engineering and experience hands-on labs in a university atmosphere. It's an opportunity for students to explore the different types of engineering available at many universities. The aim of EPIC is to expand the College of Engineering mission to K-12 students: "To educate students for careers of service, leadership and distinction in engineering or other fields by using a participatory, learn by doing, ‘hands-on’ approach".

Design Projects With Out-Of-Town Companies, Lizabeth Schlemer

Industrial and Manufacturing Engineering

The capstone design class in the industrial engineering department at California Polytechnic State University, San Luis Obispo (Cal Poly) includes projects with companies. The projects are large ambiguous facilities design problems that allow students to incorporate many aspects of the IE curriculum. For the past 15 years students have been participating in these projects with local companies. Over the past several years, companies from out of town (200 miles to the north in Mountain View or 200 miles to the south in Oxnard) have participated. These out of town companies have presented certain logistical issues, but they have proven to …

Pop-A-Wheelie Design Team, Mackenzie Hill, Thuyen Nguyen, Shaun Van't Hul

Mechanical Engineering

The purpose of this report is to illustrate the Pop-a-Wheelie design team’s progression and implementation of a concept in regards to the project sponsored by Break the Barriers (BTB). The Pop-a-Wheelie design team was tasked to design two devices that will be attached onto wheelchairs. The devices should facilitate the independence of user’s ability to pop-a-wheelie and return to an upright position without any assistance. After a list of specifications was agreed upon, the design process initiated. All customer specifications are listed in Objectives section located in Chapter 1: Introduction. A complete engineering specification table can be found in the …

Cal Poly Human Powered Helicopter, Josiah Auer, Eric Behne, Dave Berry, Rebecca Hennings, James Koch, Ian Marquardt, Josiah Mayfield, Sean Miller

Mechanical Engineering

The following report encompasses the Cal Poly Human Powered Helicopter team’s efforts during the 2010-2011 academic year. The intention of this project is to further the knowledge of human powered helicopter design and to validate an ideal configuration through experimental tests and analysis. 

A. Background

The Sikorsky Prize offered by the American Helicopter Society has been the catalyst for many attempts at Human Powered Helicopter (HPH) flight. The requirement to win the prize is a continuous, human powered flight of more than 60 seconds that stays within a 10 meter square box and reaches an altitude greater than 3 meters …

Power Steering Concept, Anthony N. Escobedo, William Ryan Flores, Russell Haverstock

Mechanical Engineering

This senior project was created in conjunction with Edwards Lifesciences. This project was created under an non-disclosure agreement and will not be submitted to any outside sources. The submitted title page will act as proof of completion.

Peripheral Soldering Of Flip Chip Joints On Passive Rfid Tags, Md Syful Islam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Flip chip is the main component of a RFID tag. It is used in billions each year in electronic packaging industries because of its small size, high performance and reliability as well as low cost. They are used in microprocessors, cell phones, watches and automobiles. RFID tags are applied to or incorporated into a product, animal, or person for identification and tracking using radio waves. Some tags can be read from several meters away or even beyond the line of sight of the reader. Passive RFID tags are the most common type in use that employ external power source to …

Mechatronics Application To Solar Tracking, Danny L. Rodriguez Jr

Purdue Polytechnic Directed Projects

The purpose of this was to design and implement a two-axis solar tracking system utilizing the National Instruments C-Rio real time controller. In order to accomplish this a prototype was modeled in CAD. This prototype used two 12 V DC motors to change a solar panel's rotation and tilt based on feedback data from three cadmium sulfide photoresistors. This configuration was chosen for its ability to create both a left-right rotational and an up/down tilt differential. In Addition this approach uses National Instruments Labview to control a solar tracking system. Using Labview add uniqueness to this project by adding a …