Mechanical Engineering Commons^™

Microstructural Evolution And Mechanical Properties Of Ultra-Fine Grained Tubular Components Processed By Severe Plastic Deformation, Mesbah Mohsen

Student Works (2020-2029)

The lightweight alloys have been widely used in various engineering applications such as automotive, aerospace, construction, and biomedical industries due to their low densities, high ductility, formability, and facile machining. However, the emerging trend for materials with high mechanical strength and plasticity hampers the widespread application of these alloys. Over the last two decades, severe plastic deformation (SPD) has been introduced as a promising approach for enhancement of the mechanical performance of the lightweight alloys through microstructural manipulations and grain refinement. However, the SPD techniques have been extensively utilized for the fabrication of non-tubular geometries and the studies on the …

Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim

Mechanical Engineering

Formula SAE is a collegiate competition hosted by SAE International with the primary goal being to design, manufacture, and race an open wheel race car. The Cal Poly Racing Formula SAE team strives for improvement every race season and has remained competitive as a result. The 2019-2020 management team determined that further research and development towards the chassis would yield the greatest performance benefit for future seasons, as the previous chassis platform limited packaging and mounting options for vehicle subsystems which interfaced with the chassis.

A redesign of the Cal Poly Racing Formula SAE team’s carbon fiber reinforced polymer monocoque …

Comparison Of Pressure-Assist Silver Sintering To Tin Silver Solder Alloy As Die Attach Material In High Power Semiconductor, Tolentino Erik Nino

Student Works (2020-2029)

The research is focused on pressure-assisted silver sintering material that is compared to tin silver solder alloy paste as used in power electronics. Material characterization, electrical tests, and reliability tests were conducted in the experiment. After drying process, it was observed that the Ag sintering paste height was reduced to approximately 40 percent. Die attach shear test showed that the average reading is about from 200 to 600 grams which are already enough to hold the dice before proceeding to the pressure sintering process. X-ray revealed that the void percent for SnAg paste sample is about 1.5 percent while pressure-assist …

Physical Behavior Of Thermally Affected Bronze And Brass, Samiul Kaiser, Mohammad Salim Kaiser

Journal of Mechanical Engineering Science and Technology (JMEST)

The physical behavior of thermally affected cast copper, aluminum bronze and brass has been studied by subjecting to heating isochronally for one hour at a range of 600°C. It shows that solid-solution hardening takes place into the Al added bronze and Zn added brass metal. Due to heating Al forms hard and brittle intermetallic of copper aluminates into the bronze metal which responses some age-hardening effects. The electrical conductivity of the metals increases initially through heat treatment due to stress relieving and finally decreases due to formation of intermetallic precipitates. The color of the heated samples are also studied through …

The Influence Of The Reference Area Of Aileron On The N2xx Aircraft Using Computational Fluid Dynamics, Siti Nur Rahmah, Gaguk Jatisukamto, Hary Sutjahjono

Journal of Mechanical Engineering Science and Technology (JMEST)

Aileron is a control surface that functions as a regulator of roll motion. The movements of the ailerons are opposite to the left and right sides. Previous studies have shown that graphs of hinge moment coefficient (Chm) values increases with increasing angle of attack. This study is to determine the aerodynamic characteristics of aileron by combining the surface area of the vane into the aileron by varying the aileron’s deflection. The calculation is performed using a numerical method in two dimensions (2D) commercial CFD simulation software. The results of the study concluded that the hinge moment coefficient for modified airfoil …

Hardness Evaluation On Ss 316l Joined With Gas Tungsten Arc Welding Under Constant Heat Treatment, Duwi Leksono, Imam Sudjono

Journal of Mechanical Engineering Science and Technology (JMEST)

The purpose of this study is to show the hardness of the GTAW welding results on SS 316L metal with surface heating during the welding process. Observations in this study used SS 316L material with heat temperature regulation on the metal surface of the welding process using heating variations of 100 ℃, 120 ℃ and 140 ℃. The welding process of SS 316L material used a welding joint model uses single V-type welding joint with an angle of 60°, a spacing of 2 mm, a root surface of 1 mm and a thickness of 5 mm. Vickers hardness test was …

The Effect Of Heat Treatment To The Erosion Rate Of Brass Composite, Aminnudin Aminnudin, Solichin Solichin

Journal of Mechanical Engineering Science and Technology (JMEST)

Brass composites can be improved their mechanical properties by the heat treatment process. The improvement of the mechanical properties of this technique is expected to increase the resistance of the composite to erosion that occurs in the environment of flow water. Brass composites used are compositeswith fly ash 5, 10, 15, and 20%. The heat treatment process was carried out using electric furnace withoutprotective gas. Composite heat up to 350°C and 400°C for 30 min. and quenching with water. Before and after the erosion test, the weight of the test specimen was weighed with analytical scales. The treatment process affects …

Performance Enhancement Of Shell And Tube Heat Exchanger On Parallel Flow With Single Segmental Baffle, Avita Ayu Permanasari, Poppy Puspitasari, Sukarni Sukarni, Retno Wulandari

Journal of Mechanical Engineering Science and Technology (JMEST)

The shell and tube heat exchanger was a tool to exchange the heat energy between fluids with different temperatures that occurred through direct or indirect contact. The energy exchange in fluids could be occurred with the same phase (liquid to liquid or gas to gas) or two fluids with different phase. To date, the process of heat transfer in the industrial field was crucial in machine work. Therefore, there were studies directed to optimize and develop the function and thermal performance of a heat exchanger by adding Baffles to the side of the shell. Vortex flow that occurs with the …

The Effect Of Solution Treatment Temperature And Quenching Media Variation In Heat Treatment Process Cu-Zn-Al Shape Memory Alloys On Shape Memory Effect And Microstructures, Wikan Jatimurti, Monica Gayatri K, Mavindra Ramadhani, Rochman Rochiem

Journal of Mechanical Engineering Science and Technology (JMEST)

Shape memory alloys (SMAs) are metal alloys with a reversible ability to recover their shape at a certain temperature after being deformed. This ability referred to as Shape Memory Effect (SME). The application of SMAs such as Ni-Ti and Cu-Zn-Al alloys usually used on automotive, biomedical, etc. The commonly used SMA is Ni-Ti because of its superior SME properties than Cu-Zn-Al, even though the price is quite higher. The SME of Cu-Zn-Al might be improved by increasing the presence of the martensite phase in its microstructure by heat treatment. The heat treatment process given to Cu-21Zn-5Al alloy is a homogenizing, …

Wavelength Decomposition Of Hybrid Additive Manufacturing Power Signals And Their Relationship With Surface Integrity, Xingtao Wang

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Additive Manufacturing (AM) has been a promising manufacturing technology in industrial applications and gained a massive amount of attention from researchers all over the world. Directed Energy Deposition (DED) is an AM process in which focused thermal energy is used to fuse materials by melting as they are deposited. One of the most significant challenges involved in current metal AM processes is improving repeatability and consistency. Substantial effort has already been invested in this area of research.

In this dissertation, a milling tool not only played a role in subtractive manufacturing but also acted as a method of monitoring the …

Preventing Delayed Cracks In Sus304 Deep Drawn Cups Using Extreme Blank Holding Forces Aided By Nanolubrication, Ibrahim Muhammad Shafiq

Student Works (2020-2029)

This study was to investigate the formation and reformation of delayed cracks of SUS304 cylindrical drawn cups under elevated blank holding force (BHF) from 8~32 kN with 1~3 wt% SiO2 nanolubricants concentrations. The widest crack-free BHF range i.e. from 29 ~ 31 kN was determined for 2 wt% of SiO2 in the experiment. Delayed cracks were also observed below and beyond this BHF range. There was an increment of frictional force at the cup flange region when entering the crack-free BHF range, as proven by the rebound in sidewall thickness, relative intensity of α′-martensite, elongated height and drawing force beyond …

Microstructural Characteristics And Mechanical Properties Of Sn-Ag-Cu Solders With Minor Additions Of Al And Zn, Yee Mei Leong

Student Works (2020-2029)

Driven by the recent trend towards miniaturization of lead free electronic products, researchers are putting immense efforts to improve the properties and reliability of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC 105 (Sn-1.0Ag-0.5Cu) solder because of economic reasons and improvement of impact resistance as compared to SAC387(Sn-3.8Ag-0.7Ag). The present work investigates the effect of minor (0.1-0.5wt.%) Aluminium (Al) and Zinc (Zn) addition to SAC105 on the bulk and interfacial structure between solder and copper substrate during reflow and after thermal aging , the mechanical properties of the solder joint and the …

Open-Source Digitally Replicable Lab-Grade Scales, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications, Part 1

This study provides designs for a low-cost, easily replicable open-source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open-source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open-source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open-source scale was found to be repeatable within 0.05 g with multiple load cells, with even better precision (0.005 …

Simultaneous Effects Of Rice Husk Silica And Silicon Carbide Whiskers On The Mechanical Properties And Morphology Of Sodium Geopolymer, Akm Rahman, Chirag Shah, Nihkil Gupta

Publications and Research

The current research is focused on developing a geopolymer binder using rice husk ash–derived silica nanoparticles. Four types of rice husks were collected directly from various rice fields of Bangladesh in order to evaluate the pozzolanic activity and compatibility of the derived rice husk ashes with precursors of sodium-based geopolymers. Silicon carbide whiskers were introduced into sodium-based geopolymers in order to evaluate the response of silicon carbide whiskers to the interfacial bonding and strength of sodium-based geopolymers along with rice husk ashes. Compression, flexural and short beam shear tests were performed to investigate the synergistic effect of rice husk ashes–derived …

Developing An Equivalent Solid Material Model For Bcc Lattice Cell Structures Involving Vertical And Horizontal Struts, Tahseen A. Alwattar, Ahsan Mian

Mechanical and Materials Engineering Faculty Publications

In this study, a body-centered cubic (BCC) lattice unit cell occupied inside a frame structure to create a so-called “InsideBCC” is considered. The equivalent quasi-isotropic properties required to describe the material behavior of the InsideBCC unit cell are equivalent Young’s modulus ( E e ) , equivalent shear modulus ( G e ) , and equivalent Poisson’s ratio ( ν e ) . The finite element analysis (FEA) based computational approach is used to simulate and calculate the mechanical responses of InsideBCC unit cell, which are the mechanical responses of the equivalent solid. Two separates finite element models are then …

Conversion Of Self-Contained Breathing Apparatus Mask To Open Source Powered Air-Purifying Particulate Respirator For Fire Fighter Covid-19 Response, Benjamin R. Hubbard, Joshua M. Pearce

Michigan Tech Publications, Part 1

To assist firefighters and other first responders to use their existing equipment for respiration during the COVID-19 pandemic without using single-use, low-supply, masks, this study outlines an open source kit to convert a 3M-manufactured Scott Safety self-contained breathing apparatus (SCBA) into a powered air-purifying particulate respirator (PAPR). The open source PAPR can be fabricated with a low-cost 3-D printer and widely available components for less than $150, replacing commercial conversion kits saving 85% or full-fledged proprietary PAPRs saving over 90%. The parametric designs allow for adaptation to other core components and can be custom fit specifically to fire-fighter equipment, including …

Design For Additive Manufacturing, Michael Charonnat, Leonardo Franco-Muñoz, Sam Noble, J.P. Purdom

Mechanical Engineering

This document outlines the critical design details and timeline for the Design for Additive Manufacturing Senior Project sponsored by Solar Turbines, Inc. The scope of this project encompasses the redesign of two of Solar Turbine’s cast parts for metal additive manufacturing in order to minimize lead time, cost, and weight. With the overall objective of performing in-depth analysis exploring affordability & feasibility, this redesign process will aid Solar Turbines in expanding their knowledge of Design for Additive Manufacturing principles and enable them to further incorporate the use of additive manufacturing into their production processes. The first part that the team …

Analysis Of Burning Wood In The Transient State And The Application To Structural Design, Roberta Veliz, Kimberly Guzman

Architectural Engineering

Determining the extent of the contribution of exposed timber on compartment fire dynamics in open floor plans is a complex process. Designers traditionally used compartmentalization design methods which create spaces where flashover is likely, given the fuel load and ventilation conditions. However, due to the large geometric dimensions and spread of fuel, fires in open floor plans are more likely to remain as localized or traveling fires. As such, an understanding of not only ignition potential but also flame spread is critical to characterizing the contribution of exposed timber. An integral step in characterizing the potential contribution is through an …

Miniaturized Ultraviolet Imager Phase Iii, Bradley D. Albright, Nicolas A. Armenta, Colin W. Harrop

Mechanical Engineering

This document details the work to date, June 9, 2020, done by the Cal Poly Mechanical Engineering senior project team, Miniaturized Ultraviolet Imager: Phase III (MUVI III), sponsored by the University of California, Berkeley – Space Sciences Laboratory (UCB SSL). MUVI III is the third senior project team of an ongoing design, MUVI: the prototype of a 2U sized CubeSat intended to capture aurora images in the ionosphere. The first team, MUVI I, finished development of the UV imager. The second team, MUVI II, designed the mirror mounting and deployable door mechanisms. The goal of MUVI phase III is to …

Effects Of New And Recycle Flux On The Mechanical Properties Of Submerged Arc Welded (Saw) Line Pipe Grade X52m And X65m, Taib Meor Mohd Adli

Student Works (2020-2029)

Two line pipe grade X52M and X65M were manufactured using submerged arc welding process. For each grade, two different welding flux condition were simulated, i.e. 100% new flux and 100% recycle flux. The flux used was aluminate basic type trade name OP 132. The outside diameter and wall thickness for X52M was 610mm x 12.7mm and for X65M was 762mm x 14.3mm. Lower weld re-entrant angle and higher weld bead height were observed in recycle flux condition. Lower weld manganese content recorded in recycle flux condition. And lower mechanical tests (i.e. tensile, impact, and hardness) value reported for recycle flux …

Development Of Reduced Chemical Kinetic Models For The Numerical Simulation Of Combustion And Emissions Behavior Of Representative Conventional And Bio-Derived Fuels, Mazen A. Eldeeb

Mineta Transportation Institute

The study addresses two of the main challenges facing combustion modeling for transportation fuels: simultaneous simulation of non-related combustion problems and reducing the computational cost of the modeling process itself. To address the first challenge, researchers determine a characteristic flame time from thermal diffusivity and laminar burning velocity. Researchers examine parametric dependence of flame time and ignition delay time on pressure, temperature and equivalence ratio for methane, based on validated chemical kinetic mechanisms. The study reveals flame time and ignition delay time show similar temperature dependence, flame time has stronger dependence on equivalence ratio and weaker dependence on pressure than …

Open Source High-Temperature Reprap For 3-D Printing Heat-Sterilizable Ppe And Other Applications, Noah G. Skrzypczak, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications, Part 1

Thermal sterilization is generally avoided for 3-D printed components because of the relatively low deformation temperatures for common thermoplastics used for material extrusion-based additive manufacturing. 3-D printing materials required for high-temperature heat sterilizable components for COVID-19 and other applications demands 3-D printers with heated beds, hot ends that can reach higher temperatures than polytetrafluoroethylene (PTFE) hot ends and heated chambers to avoid part warping and delamination. There are several high temperature printers on the market, but their high costs make them inaccessible for full home-based distributed manufacturing required during pandemic lockdowns. To allow for all these requirements to be met …

Fly Ash Based Geopolymer For High Temperature And High Compressive Strength Applications In Aggressive Environment, Aaryan Manoj Nair, Akm S. Rahman

Publications and Research

Geopolymers are the results of geosynthetic reactions between aluminosilicates and strong bases. This results in chemical bonds between aluminum (Al), Silicon (Si)and oxygen (O) composing polymer rings in tetrahedral coordination. These bonds give them widespread useful applications such as high heat bearing ceramics, and base construction material whilst being far more environmentally conscious. The purpose of the experiment is to examine the effect of Silicon Carbide whisker and inorganic glass particles on thermal and mechanical properties of Geopolymers. This study will help understand the effect of various compositions and concentrations of SiO₂ in mechanical strength. In this experiment, the …

Parametric Nasopharyngeal Swab For Sampling Covid-19 And Other Respiratory Viruses: Open Source Design, Sla 3-D Printing And Uv Curing System, Nicole Gallup, Adam Pringle, Shane Oberloier, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications, Part 1

Access to nasopharyngeal swabs for sampling remain a bottleneck in some regions for COVID19 testing. This study develops a distributed manufacturing solution using only an open source manufacturing tool chain consisting of two types of open source 3-D printing and batch UV curing, and provides a parametric fully free design of a nasopharyngeal swab. The swab was designed using parametric OpenSCAD in two components (a head with engineered break point and various handles), which has several advantages: i) minimizing print time on relatively slow SLA printers, ii) enabling the use of smaller print volume open source SLA printers, iii) reducing …

Effects Of Hard-To-Soft Segment Ratios On The Synthesis And Physico-Mechanical Properties Of Polyurethane Films, Aaron C. Wilson

Mechanical Engineering Theses

Blood-contacting cardiovascular stents often induce a secondary clotting event due to unrestricted enzymatic activities. The use of hemocompatible polyurethane coatings on these implantable devices is one of the most promising methods to reduce device rejection. In this study, four commercial polyurethane films of various thicknesses and compositions were evaluated for their anticoagulation properties. Results suggested that these films exhibited excellent thermal and physico-mechanical properties while capable of increasing contact time with blood plasma by over a thousand-fold as compared to a control surface. Due to the unknown structure and composition of these commercial films, polyurethane samples were synthesized from toluene …

Dynamic Characterization Of Duroprotect, A Fiber-Reinforced Ballistics Composite, Ivy A. Turner

Honors Theses

Dynamic characterization of materials has become increasingly common, as it is important to understand how materials behave under sudden loads. Understanding these properties can aid in material selection for novel designs. DuroProtect, a fiber-reinforced ballistics composite developed by Rӧchling, was tested for its dynamic properties at high strain-rates. The Split Hopkinson Pressure Bar (SHPB) test was used to obtain dynamic properties at high strain-rates under compressive loading conditions. Tests were initially conducted to validate force equilibriums for each sample. The data measured from the strain gages mounted on the incident and transmission bars and the elastic wave propagation theories yields …

Comparative Analysis And Dynamic Response Of Garolites Under Temperature Spectrum Using Low Velocity Impact Test, Birendra Chaudhary

Honors Theses

The purpose of this study was to examine the dynamic response of three different grades of garolites under the temperature spectrum. High-Temperature G-11 Sheet (HTG), Impact Resistance Garolite E-glass (HIG), and Economical Garolite (EG) were tested using an Instron Dynatup 8250 impact tester. Three specimens were used for all three composites and were tested at 6 different temperatures, -10^oC, 25^oC, 50^oC, 100^oC, 150^oC and 200^oC using the Low-Velocity Impact Machine with 20 Kip punch shear load cell. The results showed that HIG had the highest resistance to punch …

The Development Of All Solid-State Optical Cryo-Cooler, Junwei Meng

Optical Science and Engineering ETDs

This dissertation describes the development of an all solid-state optical cryo-cooler. Crystals of 10% wt. ytterbium-doped yttrium lithium fluoride (Yb³⁺:YLF) are used to cool an infrared HgCdTe sensor payload to an absolute temperature below 135 K, equivalent to delta T equal 138 K below ambient. This record level of cooling is accomplished with a single stage, in a completely vibration-free environment, with a corresponding cooling power of 190 mW. This milestone is made possible by the design and fabrication of an undoped YLF thermal link that efficiently shields the payload with a non-right angle kink from intense anti-Stokes …

Additive Manufacturing And How 3d Printing Is Fighting Covid-19, Raghavan Srinivasan, Ahsan Mian, Joy Gockel, Laura M. Luehrmann

Mechanical and Materials Engineering Faculty Publications

This is the fourth installment in the Shelter in Place (SiP) Lecture series. This installment covers the creative ways that 3D printing has supported efforts to combat the pandemic. It covers the basics of what 3D printing is, some of the various creative projects that have used 3D printing to combat the pandemic, among other topics and questions by the pandemic.

Materials-Processing Relationships For Metal Fused Filament Fabrication Of Ti-6al-4v Alloy., Paramjot Singh

Electronic Theses and Dissertations

Additive manufacturing (AM) is at the mainstream to cater the needs for rapid tooling and small-scale part production. The metal AM of complex geometries is widely accepted and promoted in the industry. While several metal AM technologies exist and are matured to a level where expectation in terms of design and properties are possible to realize. But the metal AM suffers from the heavy expense to acquire equipment, isotropic property challenges, and potential hazards to work with loose reactive metal powder. With this motivation, the dissertation aims to develop the fundamental aspects to print metal parts with bound Ti-6Al-4V powder …