Mechanical Engineering Commons^™

Mechanical Properties And Characterization Of Epoxy Composites Containing Highly Entangled As-Received And Acid Treated Carbon Nanotubes, Aaron Krieg, Julia A. King, Gregory M. Odegard, Timothy Leftwich, Leif K. Odegard, Paul D. Fraley, Ibrahim Miskioglu, Claire Jolowsky, Matthew Lundblad, Jin Gyu Park, Richard Liang

Michigan Tech Publications, Part 1

Huntsman–Merrimack MIRALON® carbon nanotubes (CNTs) are a novel, highly entan-gled, commercially available, and scalable format of nanotubes. As-received and acid-treated CNTs were added to aerospace grade epoxy (CYCOM® 977-3), and the composites were characterized. The epoxy resin is expected to infiltrate the network of the CNTs and could improve mechanical properties. Epoxy composites were tested for flexural and viscoelastic properties and the as-re-ceived and acid treated CNTs were characterized using Field-Emission Scanning and Transmission Electron Microscopy, X-Ray Photoelectron Spectroscopy, and Thermogravimetric Analysis. Composites containing 0.4 wt% as-received CNTs showed an increase in flexural strength, from 136.9 MPa for neat epoxy …

Electrostatic Flocking Of Salt-Treated Microfibers And Nanofiber Yarns For Regenerative Engineering, Alec Mccarthy, Kossi Loic M. Avegnon, Phil A. Holubeck, Demi Brown, Anik Karan, Navatha Shree Sharma, Johnson V. John, Shelbie Weihs, Jazmin Ley, Jingwei Xie

Mechanical Engineering Faculty Publications

Electrostatic flocking is a textile technology that employs a Coulombic driving force to launch short fibers from a charging source towards an adhesive-covered substrate, resulting in a dense array of aligned fibers perpendicular to the substrate. However, electrostatic flocking of insulative polymeric fibers remains a challenge due to their insufficient charge accumulation. We report a facile method to flock electrostatically insulative poly(ε-caprolactone) (PCL) microfibers (MFs) and electrospun PCL nanofiber yarns (NFYs) by incorporating NaCl during pre-flock processing. Both MF and NFY were evaluated for flock functionality, mechanical properties, and biological responses. To demonstrate this platform's diverse applications, standalone flocked NFY …

Atomistic Simulation Of Desalination, Ian David Durr

Symposium of Student Scholars

Atomistic Simulation of Desalination

Ian Durr, Matheus Prates, and Jungkyu Park

Kennesaw State University

In this research, we investigate the desalination capacity of three-dimensional (3D) carbon nanostructures using molecular dynamics simulations. 3D carbon nanostructures proposed here will filter seawater efficiently because of their multiple layers with holes of tunable sizes. The structure is designed to be flexible, allowing mechanical deformation during daily use. The 3D carbon nanostructure will still possess high thermal conductivity, enabling easy recycle through a simple heating process. Here, we employ LAMMPS, Large-scale Atomic/MolecularMassively Parallel Simulator distributed by Sandia National Laboratories to measure salt ion flux through …

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …

Silk Fibroin Supraparticles Created By The Evaporation Of Colloidal Ouzo Droplets, Ashley Lamb, Fengjie He, Shengjie Zhai, Hui Zhao

Mechanical Engineering Faculty Research

Due to its high biocompatibility and biodegradability, supraparticles made from silk fibroin—produced from Bombyx mori (B. mori) cocoons—can find various applications in biomedical fields. The evaporation of Ouzo droplets by not requiring energy nor a surfactant is an environmentally friendly, easy, and cost-effective strategy to fabricate three-dimensional supraparticles, tackling the so-called “coffee ring effect” associated with droplet evaporation. Silk fibroins are dissolved into quaternary droplets, comprised of ultrapure water, ethanol, trans-anethole oil, and formic acid. The Ouzo droplet is able to form an oil ring that facilitates the droplet contraction to create a three-dimensional supraparticle. Using the Ouzo effect to …

Comparison Of Concrete And Steel Jacket Methods For Reinforcing A Concrete Bridge Pier By Numerical And Experimental Studies, Hadi Faghihmaleki

Makara Journal of Technology

Various rehabilitation and strengthening procedures have been developed in recent decades. A study to determine which methods can be implemented to increase the useful life of the bridge before strengthening must be performed. In this study, the seismic behavior of a reinforced concrete bridge pier with dimension 3.5 × 3.5 m, which was reinforced by two steel and a concrete jacket, was investigated. Nonlinear geometric models and materials were analyzed to estimate the seismic parameters of the pier. Results show an increase in energy absorption, ultimate strength, and ductility for the steel jacket, as well as a greater increase in …

Effect Of Arc Plasma Sintering On The Structural And Microstructural Properties Of Fe-Cr-Ni Austenitic Stainless Steels, Parikin Parikin, M. Dani, A. Dimyati, N. D. Purnamasari, B. Sugeng, M. Panitra, A. Insani, T. H. Priyanto, S. Mustofa, Syahbuddin Syahbuddin, A. Huang

Makara Journal of Technology

X-ray diffraction techniques were performed to determine the actual crystal structure of A2 austenitic stainless steel (ASS) as-cast and A2 ASS after arc plasma sintering (APS) for 2 s. Computations were conducted on the basis of the Bragg arithmetic formula by comparing the S2 arithmetic with the interplanar spacing. The Bragg arithmetic formula is a simple series for the determination of the crystalline phase of materials based on the Miller indices of cubic shapes or other shapes. A2 ASS as-cast was identified to have a crystal structure of face-centered cubic with lattice parameter a = 3.58 Å. A similar crystal …

Trend Significance Levels Of Rain Onset And Cessation And Lengths Of The Wet And Dry Seasons In Epe, Lagos State, Nigeria, Adekunle Adedeji Alli, Olorunwa Eric Omofunmi

Makara Journal of Technology

This study aims to reduce crop failure resulting from a dry spell, which is the first occurrence of unsustainable rainfall that deceives farmers into planting. Thus, trends need to be tested using hypothesis, kurtosis, and other statistics to analyze the risks associated with unstable planting calendars and their possible mitigation strategies. The daily rainfall data from 1982 to 2018 were obtained from the archive of NASA/POWER SRB/FLASH, and the research location is Epe, Lagos State, Nigeria, which lies at latitude 6.585° N and longitude 3.962° E. Microsoft Excel was used to perform the tests. Results show that the null hypothesis …

Kinetic Modeling Study Of Laminar Burning Velocity Of Gasoline–Ethanol–Methanol Blends At Elevated Temperature And Pressure, Ahmad Syihan Auzani, Cahyo Setyo Wibowo, Riesta Anggarani, Yulianto Sulistyo Nugroho, Bambang Sugiarto

Makara Journal of Technology

Gasoline–ethanol–methanol (GEM) blends have been considered to replace pure gasoline as spark ignition engine fuel. Their physical and chemical properties and performance and emission measurements from real engines have been reported previously. However, a fundamental study that can explain the unique results of GEM compared with those of pure gasoline is lacking. This study aims to compare the laminar burning velocity of GEM blends at different mixtures, equivalence ratios, temperatures, and pressures with that of pure gasoline. A laminar flame propagation model and reaction mechanisms from the literature were were for a numerical simulation. In this study, the chemical components …

Improvement Of Electrical Properties Of Cmc-Pva Doped With Various Contents Of Lino3 As An Application For Hybrid Polymer Electrolytes, Amalia Zulkifli, Norfatihah Mazuki, Ahmad Salihin Samsudin

Makara Journal of Technology

The present work was carried out with the development of hybrid polymer electrolytes (HPEs) by using carboxymethyl cellulose (CMC)–polyvinyl alcohol (PVA) doped with different contents of lithium nitrate (LiNO3) for the determination of their structural and conduction properties. The structural analysis was conducted by using Fourier transform infra-red spectroscopy and showed the interaction between the blend host polymer and ionic dopant, which formed via the coordinating site of CMC-PVA and Li+-NO3−. The complexes of CMC-PVA doped LiNO3 led to an increment in ionic conductivity, as observed by electrical impedance spectroscopy, and the sample containing 20 wt% LiNO3 obtained the highest …

Music Information Retrieval Based On Active Frequency, Hardianto Wibowo, Wildan Suharso, Yufis Azhar, Galih Wasis Wicaksono, Agus Eko Minarno, Dani Harmanto

Makara Journal of Technology

Music is the art of combining frequencies. A balance of frequencies gives rise to a harmonious tone. Several features of music can be analyzed, and they include sociocultural background, lyrics, mood, tempo, rhythm, harmony, melody, timbre, and instrumentation. In this study, we use the frequency of instrumentation as a feature for classification because each instrument has a frequency range. To test this frequency range, we use five music genres and one music playing skill. The five genres are dangdut, electronic dance music (EDM), metal, pop/rock, and reggae. The music playing skill is acoustic. Active frequencies are tested using the k-nearest …

Predictive Delivery Man Assignment Problem Using Deep Learning, Rahmadini Payla Juarsa, Taufik Djatna

Makara Journal of Technology

Dispatching is a critical part in current online shopping. It relates to how the delivery man assignment should minimize cost along with the service from a source to an end customer with an appropriate scheduled time. The problem arises as neither enough products to deliver nor delivery men are available for dispatch, resulting in suboptimal service and a waste of money. The study aimed to formulate the cost of restaurant dispatching for inducing a deep learning-based solution with the gated recurrent unit recurrent neural network to receive hourly order data and to engage the result for near feature delivery man …

Rapid Annealing Of Perovskite Solar Cell Thin Film Materials Through Intense Pulse Light., Amir Hossein Ghahremani

Electronic Theses and Dissertations

Perovskite solar cells (PSCs) have garnered a great attention due to their rapid efficiency improvement using cheap and solution processable materials that can be adapted for scalable high-speed automated manufacturing. Thin film perovskite photovoltaics (PVs) are typically fabricated in an inert environment, such as nitrogen glovebox, through a set of deposition and annealing steps, each playing a significant role on the power conversion efficiency (PCE), reproducibility, and stability of devices. However, atmospheric processing of PSCs would achieve lucrative commercialization. Therefore, it is necessary to utilize materials and methods that enable successful fabrication of efficient PSCs in the ambient environment. The …

Toward An Understanding Of Fundamental Mechanisms In Transitional And Turbulence Flow Control, Ethan A. Davis

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

Turbulence is an emergent phenomenon found throughout nature and engineering, alike. It plays a vital role in the aquatic locomotion of organisms, scalar mixing, fluid transport, shipping and transportation, and even the flow of biological fluids in the human body. Therefore, it is of utmost importance in both a practical and engineering sense to better understand turbulence with the goal of better controlling it. This dissertation focuses broadly on better understanding the underlying mechanisms behind wall-bounded turbulent flows, with an emphasis on exploiting those mechanisms for turbulence flow control.

We developed a numerical simulation to study the effect of slip …

Development Of A Mash Tl-3 Compliant Parapet Mounted Fence, Luis Rodriguez Alvizo

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

When roadways pass over railway tracks, there is a risk that debris from the roadway or pedestrians may fall onto the tracks and interfere with railway operations. Because of this, state Departments of Transportation (DOTs) commonly install debris fences in conjunction with bridge rails over railway tracks. However, the safety performance of debris fence systems when impacted by an errant vehicle has not been demonstrated through full-scale crash testing. Thus, the objective of this research was to develop a new, parapet-mounted debris fence for the Iowa DOT according to safety performance guidelines included in the American Association of State Highway …

Electrochemical Corrosion Properties Of Ternary Al And Quaternary Zr Added Bell Metal In 0.1m Nacl Solution, Sakib Al Razi Khan, Mohammad Ashfaq Hossain, Maglub Al Nur, Mohammad Salim Kaiser

Journal of Mechanical Engineering Science and Technology (JMEST)

The electrochemical corrosion property of ternary Al and quaternary Zr added Bell metal in 0.1M Sodium Chloride solution has been experimentally conducted at room temperature. Electrochemical impedance spectroscopy (EIS) method and Potentiodynamic polarization technique are used to carry out the electrochemical investigation. Microhardness test is also conducted for all three alloys and it reveals that Al addition increases the hardness of bell metal due to the formation of different intermetallic precipitates of Cu and Al. Optical Micrograph as well as Scanning Electron Micrograph have also been studied to characterize their surface condition. It is found that Zr addition refines the …

Evaluating Storage And Effective Moduli Of In Situ Polymerised And Melt Extruded Pa6 Graphite (G) Composites, Muneer Umar, Michael Ikpi Ofem, Auwal Sani Anwar, Muhammad Murtala Usman

Journal of Mechanical Engineering Science and Technology (JMEST)

Four PA6/graphite (G) composites systems were made. Two using in situ polymerisation equivalent in mixing strain and two systems melt extrusion of equivalent processing strain. The effective modulus of the carbons, room temperature storage modulus and storage modulus at 80 ⁰C were evaluated. The composite/unfilled PA6 ratios at E25 and that at E80 for the in situ polymerised system IG 40/10 are 1.37 and 1.63, respectively. For the in situ polymerised system IG 20/20, the same were 1.96 and 2.28, respectively. For the melt-extruded systems, G 100/6 had the best E25 ratio of 1.67 and E80 of 2.03, whereas the …

The Effect Of Thickness And Type Of Material On The Sheared Edge Characteristics Of Keychain Cranioplasty Plate Blanking Product Using Eccentric Press Machine, Didin Zakariya Lubis, Lea Rachmat Indrasepta, Redyarsa Dharma Bintara, Rizky Ramadhan, Agung Budi Darmawan

Journal of Mechanical Engineering Science and Technology (JMEST)

Keychain cranioplasty plate product has the potential to be produced using the blanking process because it is faster, low-cost, and requires low-energy consumption compared to other mechanical operations. This research aimed to find the effect of material thickness and type on the sheared edge characteristics of keychain cranioplasty plate using the blanking process to meet the international health standard. Experimental research conducted using an eccentric press machine with 40 tons capacity. This research’s test material parameters of titanium (Ti-6AL-4V) and stainless steel (SS-316L) were the 0.5 mm, 0.6 mm, and 0.8 mm thickness with a maximum blanking velocity of 3000 …

Effect Of Dcrp And Dcsp Polarity On The Depth Of Penetration Of Smaw On Low Carbon Steel Astm A36 Using E7018 Electrode, Ma'mun Hidayat, Helleni Febnesia, Sulaeman Deni Ramdani

Journal of Mechanical Engineering Science and Technology (JMEST)

The study aims to determine the level of penetration depth using SMAW (Shielded Metal Arc Welding) Process based on the polarity type of DCRP (Direct Current Reverse Polarity) and DCSP (Direct Current Straight Polarity). This research used ASTM A36 low carbon steel plate with thickness of 6 mm and length of 200 mm, Electrode E7018 LB-52-18 ∅ 3.2 mm, and with current parameters of 90 A, 100 A, 110 A, 120 A and 130 A and 70 ° welding arc angle. The method used the experimental research. Data collection techniques applied direct observation techniques and descriptive statistical data analysis techniques. …

Camshaft Failure Simulation With Static Structural Approach, Riduwan Prasetya, Andoko Andoko, Suprayitno Suprayitno

Journal of Mechanical Engineering Science and Technology (JMEST)

A failure happens within the camshaft of the minibus when the vehicle is in utilize. The camshaft was a fracture within the bearing between the primary cylinder exhaust valve and the second cylinder suction. This simulation aims to find the causes of camshaft failure utilizing the finite element method with a static structural approach, including simulations of deformation, strain, stress, fatigue life (stress-life and strainlife), and cracks. The method used in this paper is the finite element method with a static structural approach by ANSYS software. The camshaft material is a gray cast iron designed using Solidworks. Pre-processing includes meshing …

The Effect Of Multi-Extrusion Process Of Polylactic Acid On Tensile Strength And Fracture Morphology Of Filament Product, Muhamad Syaifuddin, Heru Suryanto, Suprayitno Suprayitno

Journal of Mechanical Engineering Science and Technology (JMEST)

Polylactic acid (PLA) is one of the most used materials in FDM 3D Printing. Large-scale consumption of PLA on an industrial scale could cause environmental and efficiency problems. Thus, PLA waste and industry waste need to be recycled to limit excessive waste. This study aimed to investigate the change in mechanical property, morphology, and structure of mechanically recycled PLA. Recycling was performed 12 times using the extrusion process with an extrusion temperature nozzle of 170°C. The SEM, structural analysis, and amorphous-crystalline analysis used XRD. The results showed a gradual decrease of tensile strength from each recycle with a total of …

Fully Coupled Internal Radiative Heat Transfer For The 3d Material Response Of Heat Shield, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

The radiative transfer equation (RTE) is strongly coupled to the material response code KATS. A P-1 approximation model of RTE is used to account for radiation heat transfer within the material. First, the verification of the RTE model is performed by comparing the numerical and analytical solutions. Next, the coupling scheme is validated by comparing the temperature profiles of pure conduction and conduction coupled with radiative emission. The validation study is conducted on Marschall et al. cases (radiant heating, arc-jet heating, and space shuttle entry), 3D Block, 2D IsoQ sample, and Stardust Return Capsule. The validation results agree well for …

Reduced-Order Modeling Of Loosening In Bolted Joints And Dynamic Interactions Between Axially Aligned Threaded Joints, Sandro Aldana

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

Maintaining effective preload in bolted joints is critical for ensuring long-term performance and safety throughout the operation of any assembled structure. The loosening of bolted joints has been studied since the Industrial Revolution, but modeling approaches have only emerged over the past three decades. Although existing approaches are capable of simulating or predicting loosening in a single joint consisting of a single bolt, they are too computationally expensive to be used to model loosening in large structures consisting of many bolts. The objective of this thesis is to construct and employ a reduced-order modeling (ROM) approach that treats the internal …

Thermal And Mechanical Analysis Of Bombyx Mori Silk Nanofibers, Justin Busnot

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

This thesis presents a study on the thermomechanical properties of Bombyx Mori silk nanofibers. These nanofibers were obtained from silkworm cocoons which were degummed to separate the fibroin and the sericin, the two proteins that make up silk. The fibroin was then centrifuged to remove insoluble particles and stored and 4°C before the electrospinning process. A parametric study of the electrospinning process was carried out in order to identify the factors allowing to obtain optimal mechanical properties. The current as well as the flow rate applied, the diameter of the syringe, the distance separating the syringe from collector or even …

Mechanical Properties And Microstructure Characteristics Of Alloy Parts Produced By Laser Powder Bed Fusion (Lpbf) Method, Hong Yao

LSU Doctoral Dissertations

Additive manufacturing (AM) is a rapid prototyping technology to produce fully functional and complex designing objects. As one of the AM methods, Laser Powder Bed Fusion (LPBF) has gained the most attention from both academic researchers and industrial companies. During the LPBF process, metal powders are applied layer by layer, which can be 20 microns to 50 microns in thickness. After a layer is prepared, a high-power laser, which is commonly controlled by a scanning head, is used to selectively melt the interested area of a 2D geometry which is designed in a computer aided designing software. LPBF method can …

Optimization Of Load-Bearing And Impact Energy Absorption Capacities Of Honeycomb Structures By Density Gradation, Oyindamola Khadijat Rahman

Theses and Dissertations

Density gradation has been analytically and experimentally proven to enhance the load-bearing and energy absorption efficiency of cellular solids. This research focuses on the analytical optimization (by virtual experiments) of polymeric honeycomb structures made from flexible thermoplastics to achieve density-graded structures with desired mechanical properties. The global stress-strain curves of single-density honeycomb structures are used as input to an analytical model that enables the characterization of the constitutive response of density-graded hexagonal honeycombs with discrete and continuous gradations and for various gradients. The stress-strain outputs are used to calculate the specific energy absorption, efficiency, and ideality metrics for all density-graded …

Tribological Studies Of Thick Polytetrafluoroethylene Coatings Enhanced By Polydopamine And Nanoparticles, Sujan Kumar Ghosh

Graduate Theses and Dissertations

Polytetrafluoroethylene (PTFE) is a popular low friction solid lubricant with high chemical and thermal stability. Thick PTFE coatings have the potential for many tribological applications, such as replacing Tin-based Babbitt materials in journal bearings. However, the weak bonding strength to the substrate and the high wear rate of PTFE coatings are current limiting factors. The lack of understanding of their tribological properties and wear mechanisms in oil-lubricated conditions and how coating thickness affects the tribological performance further hindered the use of PTFE coatings. In this dissertation, polydopamine (PDA), a bio-inspired adhesive, is used as an underlayer for or as a …

Phase-Field Modeling Of The Polymer Membrane Formation Process For Micro- And Ultra-Filtration, Michael Rosario Cervellere

Graduate Theses and Dissertations

Porous polymer membrane filters are widely used in separation and filtration process. Micro- and ultra-filtration membranes are commonly used in biopharmaceutical applications such as filtering viruses and separating proteins from a carrier solution. The formation of these membrane filters via phase inversion is a complex and interconnected process where varying casting conditions can have a wide variety of effects on the final membrane morphol- ogy. Tailoring membrane filters for specific performance characteristics is a tedious and time consuming process. The time and length scales of membrane formation make it extremely difficult to experimentally observe membrane formation. Modeling the membrane formation …

Review: Factors Affecting Composite Laminates Against Lightning Strikes, Aaryan Manoj Nair

Publications and Research

Lightning strike protection (LSP) have recently been a newly developing field particularly with the emergence of graphene thin film integration into carbon fiber composite structures. This technology has a widespread application in airplanes, wind turbines, and other instruments which are susceptible to frequent lightning strikes. Electrical discharge of the instrument in a safe manner is vital for the safety of the passengers (in the case of flights) as well as the integrity of the aircraft structures because of their specific mechanical and structural properties, which are essential for their functioning. The purpose of the study is to fabricate graphene thin …

Anisotropic Plasticity Modeling Of Thin Sheets And Its Application To Micro Channel Forming Of Steel Foils, Jie Sheng

Mechanical Engineering Research Theses and Dissertations

Thin sheet metals and ultrathin metal foils produced by industrial rolling processes are textured polycrystalline materials and their mechanical behaviors may depend strongly on the orientation of applied loading. Consideration of such plastic anisotropy in advanced modeling of these materials is of the paramount importance in designing optimal manufacturing processes for automotive and other applications using finite element methods. This research addresses several critical issues in anisotropic plasticity modeling and its applications in analyzing micro channel forming of ultrathin stainless-steel foils. An experimental study has first been carried out on the accuracy and sensitivity of measuring the plastic strain ratios …