Engineering Commons^™

Material Synthesis And Machine Learning For Additive Manufacturing, Jaime Eduardo Regis

Open Access Theses & Dissertations

The goal of this research was to address three key challenges in additive manufacturing (AM), the need for feedstock material, minimal end-use fabrication from lack of functionality in commercially available materials, and the need for qualification and property prediction in printed structures. The near ultraviolet-light assisted green reduction of graphene oxide through L-ascorbic acid was studied with to address the issue of low part strength in additively manufactured parts by providing a functional filler that can strengthen the polymer matrix. The synthesis of self-healing epoxy vitrimers was done to adapt high strength materials with recyclable properties for compatibility with AM …

Insole Fall Prevention Device, Nick M. Hughes, Andrew M. Slaboda

Biomedical Engineering

Falls among the aging population occur every single day, with 1 in every 5 resulting in some injury and 300,000 hospitalized every year with a hip fracture [1]. The most popular and effective way to mitigate these falls is through physical therapist intervention. However, with the increased popularity in telerehab, many patients at risk for falls cannot accurately convey their gait tendencies to their physical therapists from the comfort of their home or while not in direct contact with the PT. A device like an insole, implanted with force sensors, which measures different parts of a patient’s foot, could convey …

Crystal Growth And Property Tuning Of Layered Magnetic Topological Semimetals, Krishna Pandey

Graduate Theses and Dissertations

The demand for energy-efficient devices has been growing rapidly due to the need for data-driven technologies and the global energy crisis. As device size approaches the atomic scale, the miniaturization of electronic devices may stop in the near future unless fundamentally new materials or device concepts are developed. The emergent topological materials with exotic properties show remarkable robustness against crystal lattice defects, which are promising for next-generation technology. These materials host exotic properties such as high mobility, large magnetoresistance, chiral anomaly, and surface Fermi arcs, etc. Among various topological materials, the ZrSiS-family materials exhibit two types of Dirac states, which …

Investigation On Electrochemical Processes Of P-Aminothiophenol On Gold Electrode Of Nanostructures, Hui-Yuan Peng, Jia-Zheng Wang, Jia Liu, Huan-Huan Yu, Jian-De Lin, De-Yin Wu, Zhong-Qun Tian

Journal of Electrochemistry

Electrochemical reactions on nanostructured noble electrodes have received much attention, however, the reaction mechanism and reaction kinetics are still difficult to be studied. Probe molecule can give an insight to the investigation of electrochemical reactions on noble electrodes with nanostructures. In this paper, the electrochemical process of p-aminothiophenol (PATP) adsorbed on the gold electrode was studied by electrochemical cyclic voltammetry and surface-enhanced Raman spectroscopy (SERS). Here, we used one-step sodium citrate reduction method (Frens method) to synthesize gold nanoparticles, which are used to construct the nanostructured gold electrode. The Raman electrolytic cell used was based on the traditional three-electrode electrolytic …

Study On Electrochemical Conversion Of Ammonium Sulfate To Ammonium Persulfate In Acetylpyrazine Wastewater, Yi-Jie Wang, Dong-Fang Niu, Xin-Sheng Zhang

Journal of Electrochemistry

Acetylpyrazine is an important spice and also plays important roles in biology, medicine and other fields. However, the wastewater containing ammonium persulfate, ferric ion (Fe³⁺), pyrazine, and a large amount of ammonium sulfate was produced during the production of acetylpyrazine. In this study, ammonium sulfate in acetylpyrazine wastewater was electrolytically converted into ammonium persulfate for economic benefits. Using platinum as an anode and graphite as a cathode, the influence factors of the electrolysis process (including the composition of the anolyte, the current density, the temperature, etc.) were firstly investigated without interference from other compositions. Under the optimal condition, …

Study On Electrodeposition Of Antimony In Choline Chloride-Ethylene Glycol Eutectic Solvent, Hao Wang, Xiao-Zhou Cao, Xiang-Xin Xue

Journal of Electrochemistry

Antimony is a chemically stable metal that has been widely used in industry, military and other fields. The use of electrodeposition to prepare antimony coating has the advantages of simple operation and low cost. The deep eutectic solvent (DES) is a eutectic mixture composed of a hydrogen bond donor and a hydrogen bond acceptor at a fixed molar ratio. It has the advantages of wide electrochemical window, high thermal stability, easy preparation, and low cost. Selecting DES as the electrolyte for electrodeposition can avoid the hydrogen evolution reaction of the aqueous system and the toxicity of ionic liquids. In recent …

Adjusting The Alloying Degree Of Pt3Zn To Improve Acid Oxygen Reduction Activity And Stability, Tian-En Zhang, Ya-Ni Yan, Jun-Ming Zhang, Xi-Ming Qu, Yan-Rong Li, Yan-Xia Jiang

Journal of Electrochemistry

Proton exchange membrane fuel cell (PEMFC) is a new type of energy device, a relatively excellent way to achieve carbon neutrality. However, due to the relatively slow reaction rate of oxygen reduction reaction (ORR) at the cathode, platinum (Pt) is the key material of the cathode catalyst. However, Pt is a kind of noble metal, and its high cost restricts the PEMFC commercialization process. At present, the main approach is to combine transition metals with Pt to prepare Pt-based alloys and to reduce the use of Pt. Pt-based alloys are excellent catalysts for ORR, improving both the activity and stability, …

Effects Of Electrode Shape On Lithiation Process Of Lithium-Ion Battery Electrodes, Shi-Wei Sun, Jian-Jun Nie, Yi-Cheng Song

Journal of Electrochemistry

This paper studies the influence of electrode shape on the lithiation process of lithium ion batteries. Both experimental observation and numerical simulation are employed to investigate the competitive interaction between the diffusion of lithium ions in both solid and liquid phases and the lithium intercalation reaction at the electrode surface. Experimental cells were prepared with the anode and cathode being placed parallel, leaving the latter embracing the former. An experimental device based on CCD camera was set up for in situ observation of electrode lithiation. The lithiation levels of the graphite anodes were estimated according to the observed color profile. …

Preparation Of Pt@Basrtio3 Nanostructure And Its Properties Towards Photoelectrochemical Ammonia Synthesis, Jing Zhang, Rui-Xia Guo, Jian-Jun Fu, Shi-Bin Yin, Pei-Kang Shen, Xin-Yi Zhang

Journal of Electrochemistry

Ammonia is an important industrial raw material and a potential green energy. Using renewable energy to convert nitrogen into ammonia under ambient condition is an attractive method. However, the development of efficient photoelectrochemical ammonia synthesis catalysts remains a challenge. Perovskite such as BaSrTiO₃ (BST) is a good photocatalytic material. However, BST is active under ultraviolet light and has a high recombination rate of photogenerated electron-hole pairs. By dispersing precious metals, it can effectively regulate the absorption of sunlight by BST. In this work, we used a two-step method to prepare BST. The H₂PtCl₆·6H₂O …

Multi-Scale Simulation Revealing The Decomposition Mechanism Of Electrolyte On Lithium Metal Electrode, Yan-Yan Zhang, Yue Liu, Yi-Ming Lu, Pei-Ping Yu, Wen-Xuan Du, Bing-Yun Ma, Miao Xie, Hao Yang, Tao Cheng

Journal of Electrochemistry

Lithium metal is considered as an ideal anode material for next-generation high energy density batteries with its high specific capacity and low electrode potential. However, the high activity of lithium metal can lead to a series of safety issues. For example, lithium metal will continuously react chemically with the electrolyte, forming unstable the solid electrolyte (SEI) films. In addition, lithium dendrites can be formed during cycling, which can puncture the SEI film and cause short circuits in the battery. These drawbacks greatly hinder the commercial application of lithium metal. To solve the above problems, it is important to understand the …

Detection And Identification Of Disturbances By Spectral Analysis Of Structure-Borne Noise During The Production Of A Sealing Seam, Felix Kruppa, Lars Meisenbach, Berend Oberdorfer Dr.-Ing., Bernd Wilke Prof. Dr.-Ing.

Journal of Applied Packaging Research

When sealing, disturbances or errors can occur that impair the quality of the sealing seam and, in the worst case, lead to leaks. It is therefore important to identify and eliminate defective packages during production and to minimize the elimination by readjusting machine parameters. The aim of this article is the clear identification of seam quality problems on a vertical forming, filling and sealing machine SVE2520 by evaluating process parameters during the manufacturing process. For this purpose, the structure-borne noise is measured for each seal in order to identify not-usual curves. These not-usual curves are related to different disturbances or …

A Deep Reinforcement Learning Approach With Prioritized Experience Replay And Importance Factor For Makespan Minimization In Manufacturing, Jose Napoleon Martinez

LSU Doctoral Dissertations

In this research, we investigated the application of deep reinforcement learning (DRL) to a common manufacturing scheduling optimization problem, max makespan minimization. In this application, tasks are scheduled to undergo processing in identical processing units (for instance, identical machines, machining centers, or cells). The optimization goal is to assign the jobs to be scheduled to units to minimize the maximum processing time (i.e., makespan) on any unit.

Machine learning methods have the potential to "learn" structures in the distribution of job times that could lead to improved optimization performance and time over traditional optimization methods, as well as to adapt …

Novel Thermal Coating For High-Speed Airplanes, Abinash Satapathy, Lakshay Battu, Liam Watson, Nazanin Rajabi

Symposium of Student Scholars

In comparison to various other materials, Carbon Fiber, specifically Carbon Fiber Reinforced Polymers (CFRP), is pre-eminent amongst other materials for use on aeronautical systems. Due to its high specific strength (strength-to-weight ratio), CFRP is prominent for carrying heavy loads while maintaining a lightweight build. However, when influenced by heat resulting from air resistance, CFRP is known to undergo serious degradation that would significantly decrease the effectiveness of the polymers. To prevent this degradation and maintain the strength of the CFRP, thermal protective layers (TPLs) are designed to shield the CFRP from heat exposure. This research is focused on the examination …

From 2d Images To 3d Virtual Reality: A Digital Application In Cultural Heritage, Garrett Ronny Hucks

Undergraduate Research Competition

The digital documentation and preservation of historic and cultural sites are urgent needs for local governments due to concerns regarding structural damage and deterioration over the long term. With new technologies like augmented reality (AR), virtual reality (VR), and mixed reality (MxR), enabling 3D, immersive, virtual experiences become feasible. In this poster presentation, we outline a novel methodology that allows site owners to capture, digitally preserve, and then view these historic sites in the virtual environment. To this end, 2D photographs of a historic site are first taken and then generated into a 3D point cloud in Agisoft. Thereafter, we …

Method Of Embedded Imperfections For The Direct Simulation Of Deformation Instabilities In Film-Substrate Structures, Siavash Nikravesh Kazeroni

Mechanical Engineering ETDs

In this dissertation, a novel finite-element methodology called “embedded imperfections” is proposed and employed for computationally simulating various types of deformation instabilities observed in film-substrate structures subjected to mechanical loading. The approach involves the incorporation of elements having distinctive material properties within the film-substrate interface. One can interpret this practice as a deliberate distribution of material defects within the numerical model. It has been shown that embedded imperfections not only can trigger the onset of instability, but also can lead to “direct” simulation of deformation instability problems in that primary and subsequent instability modes can all be captured in a …

Machine Learning Assisted Discovery Of Shape Memory Polymers And Their Thermomechanical Modeling, Cheng Yan

LSU Doctoral Dissertations

As a new class of smart materials, shape memory polymer (SMP) is gaining great attention in both academia and industry. One challenge is that the chemical space is huge, while the human intelligence is limited, so that discovery of new SMPs becomes more and more difficult. In this dissertation, by adopting a series of machine learning (ML) methods, two frameworks are established for discovering new thermoset shape memory polymers (TSMPs). Specifically, one of them is performed by a combination of four methods, i.e., the most recently proposed linear notation BigSMILES, supplementing existing dataset by reasonable approximation, a mixed dimension (1D …

Investigating The Possibility Of Using Smelted Water-Cooled Copper Slag Regolith As A Terrestrial Based Lunar Regolith Simulant, Scott A. Morley

Graduate Theses & Non-Theses

There is a need for a stable, efficient, and cost-effective option of a terrestrial lunar regolith simulant that can be easily made and at a lower cost to the consumer. A lunar regolith is the layer of unconsolidated rocky material covering bedrock that is on planets. All simulants fabricated for the moon, are based off three types of lunar regolith areas. The first is the lunar highlands which are the high areas of the moon, these areas are anthracitic. The second is lunar mare which is the meteoroid bombarded areas of the moon that look like dark grey areas from …

Treatment Of Mine Tailings Through Two Methods Of Calcite Precipitation: (I) Using Natural Mineral Trona, (Ii) Microbially Induced Calcite Precipitation Via Denitrification, Nathaniel Small

Graduate Theses & Non-Theses

Mine tailings not only pose environmental risks such as dust emission and acid mine drainage but also present geotechnical risks in cases of tailings dam failures which could lead to loss of human life and severe damages to infrastructure. In-situ cementation of tailings has the potential to reduce the risks associated with such failures as well as the related environmental problems. Over the years, different methods of chemically and microbially induced cementation of tailings have been examined many of which have shown promising results on a laboratory scale and some even on a ϐield scale. In this paper, a new …

Me-Em Enewsbrief, March 2022, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Ultra-Broadband And Polarization-Insensitive Metasurface Absorber With Behavior Prediction Using Machine Learning, Shobhit K. Patel, Juveriya Parmar, Vijay Katkar, Fahad Ahmed Al-Zahrani, Kawsar Ahmed

Department of Mechanical and Materials Engineering: Faculty Publications

The solar spectrum energy absorption is very important for designing any solar absorber. The need for absorbing visible, infrared, and ultraviolet regions is increasing as most of the absorbers absorb visible regions. We propose a metasurface solar absorber based on Ge₂Sb₂Te₅ (GST) substrate which increases the absorption in visible, infrared and ultraviolet regions. GST is a phase-changing material having two different phases amorphous (aGST) and crystalline (cGST). The absorber is also analyzed using machine learning algorithm to predict the absorption values for different wavelengths. The solar absorber is showing an ultra-broadband response covering a 0.2–1.5 …

Method Of Making Hinged Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A method is provided for fabricating a passive optical sensor on a tip of an optical fiber. The method includes perpendicularly cleaving a tip of an optical fiber and mounting the tip of the optical fiber in a specimen holder of a photosensitive polymer three-dimensional micromachining machine. The method includes forming a three-dimensional microscopic optical structure within the photosensitive polymer that comprises a two cavity Fabry-Perot Interferometer (FPI) having a hinged optical layer that is pivotally coupled to a suspended structure. The method includes removing an uncured portion of the photosensitive polymer using a solvent. The method includes depositing a …

An Additive Incorporated Non-Nucleophilic Electrolyte For Stable Magnesium Ion Batteries, Mao-Ling Xie, Jun Wang, Chen-Ji Hu, Lei Zheng, Hua-Bin Kong, Yan-Bin Shen, Hong-Wei Chen, Li-Wei Chen

Journal of Electrochemistry

Non-nucleophilic electrolytes are promising next-generation highly stable electrolytes for magnesium-ion batteries (MIBs). However, a passivation layer on Mg metal anode usually blocks Mg²⁺ diffusion, leading to poor reaction kinetics and low Coulombic efficiency of the Mg plating/stripping in these electrolytes. Here we explore the utilization of phenyl disulfide (PDF) as a film-forming additive for non-nucleophilic electrolytes to regulate the interfacial chemistry on Mg metal anode. Phenyl-thiolate generated from the PDF additive was found to suppress the unfavorable surface blocking layer, resulted in a high Coulombic efficiency of up to 99.5% for the Mg plating/stripping process as well as a …

In Situ Characterization Of Electrode Structure And Catalytic Processes In The Electrocatalytic Oxygen Reduction Reaction, Ya-Chen Feng, Xiang Wang, Yu-Qi Wang, Hui-Juan Yan, Dong Wang

Journal of Electrochemistry

As an electrochemical energy conversion system, fuel cell has the advantages of high energy conversion efficiency and high cleanliness. Oxygen reduction reaction (ORR), as an important cathode reaction in fuel cells, has received extensive attention. At present, the electrocatalysts are still one of the key materials restricting the further commercialization of fuel cells. The fundamental understanding on the catalytic mechanism of ORR is conducive to the development of electrocatalysts with the enhanced activity and high selectivity. This review aims to summarize the in situ characterization techniques used to study ORR. From this perspective, we first briefly introduce the advantages of …

Synchrotron X-Rays Characterizations Of Metal-Air Batteries, Ya-Jie Song, Xue Sun, Li-Ping Ren, Lei Zhao, Fan-Peng Kong, Jia-Jun Wang

Journal of Electrochemistry

The rapid development of electric vehicles urgently requires high-energy-density batteries. Recently, metal-air batteries have attracted much attention in industry and academia for their ultra-high theoretical energy densities. However, the practical application of metal-air batteries is severely impeded by multiple drawbacks, including severe side reactions, low energy efficiency, and limited cycle life. Understanding the reaction mechanism of the cell and further developing effective strategies are beneficial for the practical application of metal-air batteries. In the past decade, advanced characterization techniques have accelerated the development of metal-air batteries. In particular, synchrotron radiation-based characterization techniques have been widely applied to the mechanistic study …

In-Situ/Operando57Fe Mössbauer Spectroscopic Technique And Its Applications In Nife-Based Electrocatalysts For Oxygen Evolution Reaction, Jafar Hussain Shah, Qi-Xian Xie, Zhi-Chong Kuang, Ri-Le Ge, Wen-Hui Zhou, Duo-Rong Liu, Alexandre I. Rykov, Xu-Ning Li, Jing-Shan Luo, Jun-Hu Wang

Journal of Electrochemistry

The development of highly efficient and cost-effective electrocatalysts for the sluggish oxygen evolution reaction (OER) remains a significant barrier to establish effective utilization of renewable energy storage systems and water splitting to produce clean fuel. The current status of the research in developing OER catalysts shows that NiFe-based oxygen evolution catalysts (OECs) have been proven as excellent and remarkable candidates for this purpose. But it is critically important to understand the factors that influence their activity and underlying mechanism for the development of state-of-the-art OER catalysts. Therefore, the development of in-situ/operando characterizations is urgently required to detect key intermediates along …

Closed-Loop Control Of Meltpool Temperature In Directed Energy Deposition, Ziyad M. Smoqi, Ben Bevans, Aniruddha Gaikwad, James Craig, Alan Abul-Haj, Brent Roeder, Bill Macy, Jeffrey E. Shield, Prahalada K. Rao

Department of Mechanical and Materials Engineering: Faculty Publications

The objective of this work is to mitigate flaw formation in powder and laser-based directed energy deposition (DED) additive manufacturing process through close-loop control of the meltpool temperature. In this work, the meltpool temperature was controlled by modulating the laser power based on feedback signals from a coaxial two-wavelength imaging pyrometer. The utility of closed-loop control in DED is demonstrated in the context of practically inspired trapezoid-shaped stainlesssteel parts (SS 316L). We demonstrate that parts built under closed-loop control have reduced variation in porosity and uniform microstructure compared to parts built under open-loop conditions. For example, post-process characterization showed that …

Design And Testing Of A Composite Compressor Rotor, Mauro Noel V. De Leon

Theses and Dissertations

Additive manufacturing (AM) and molding are manufacturing methods known for building representations or replicas of conceptualized engine components, but was considered impractical for manufacturing operating engine components. More recent technology has rendered composite materials (combining high-temperature polymers and fiber reinforcement) capable of withstanding the temperature and structural requirements to compete with conventional turbomachinery metals. This study explores the application of several high-temperature polymers (ULTEM 9085, Onyx-Carbon fiber, and Epoxy-Carbon fiber) and their survivability in the operating conditions of a P400 Engine compressor. The tests conducted for this study determined their viability as compressor materials. This study required conducting tensile specimen …

Thermal Relaxation Of Shot Peen Induced Residual Stresses In A Nickel-Base Superalloy, Bryce E. Van Velson

Theses and Dissertations

Shot peening induces compressive residual stresses in components that positively influence fatigue life. Thermal and mechanical loading causes those residual stresses to relax. The hole drilling method and xray diffraction is used to measure the thermal relaxation of residual stresses in the nickel-base superalloy ME3.

A Study On The Early Stages Of Degradation Of Multi-Component Alloy Surfaces In Extreme Environments Using The Multi-Cell Monte Carlo Method, Tyler D. Dolezal

Theses and Dissertations

A computational toolset is presented and used in two examples that examined the interactions between structural materials and their extreme environments. A multi-cell Monte Carlo algorithm was developed to generate thermodynamically realistic solid-state alloy systems. These structures served as the foundation upon which surface slab models were generated. The tedious procedure of generating surface slab models from bulk structures was automated. The tools were used to study the high temperature surface corrosion resistance of a high-entropy alloy, Al₁₀Nb₁₅Ta₅Ti₃₀Zr₄₀, and a nickel-based alloy, Ni₇₀Nb₁₀W₂₀, under …

Computational Based Investigation Of Lattice Cell Optimization Under Uniaxial Compression Load, Derek G. Spear, Jeremiah S. Lane, Anthony N. Palazotto, Ryan A. Kemnitz

Faculty Publications

Structural optimization is a methodology used to generate novel structures within a design space by finding a maximum or minimum point within a set of constraints. Topology optimization, as a subset of structural optimization, is often used as a means for light-weighting a structure while maintaining mechanical performance. This article presents the mathematical basis for topology optimization, focused primarily on the Bi-directional Evolutionary Structural Optimization (BESO) and Solid Isotropic Material with Penalization (SIMP) methodologies, then applying the SIMP methodology to a case study of additively manufactured lattice cells. Three lattice designs were used: the Diamond, I-WP, and Primitive cells. These …