Materials Science and Engineering Commons^™

Optimization Of Bearing Design In Centrifugal Pumps Using Finite Element And Experimental Methods: Application At South Refineries Company, Basra, Mohammed Hasab Naser Al-Mtasher

Al-Esraa University College Journal for Engineering Sciences

In the study, nonlinear vibration and thermo-mechanical characteristics of centrifugal pump bearings utilized in the cooling tower system of South Refineries Company (Basra) were properly examined using a combined experimental and numerical method. The intent of the study was to learn the impact of misalignment, the nature of the lubrication film, and thermal gradients on the stability of the operation of these bearings and their service life under realistic industry environment conditions. Finite element model (FEM) was constructed and tested on the basis of real field data obtained at the working pumps that allowed realistic distribution of stress and temperature. …

Effect Of Heat Treatments On The Corrosion Resistance Of A Trip Steel And Its Evaluation By Non-Destructive Testing, Karla Ivette Vega-Nava, Ariosto Medina-Flores, Marco Antonio Espinosa-Medina, José Sergio Pacheco-Cedeño, Héctor Guillermo Carreón-Garcidueñas, Francisco Fernando Curiel-López, Jose Jaime Taha-Tijerina

Mechanical Engineering Faculty Publications

The development of advanced high-strength steels (AHSS) for the automotive industry requires optimizing the balance between mechanical properties and durability in aggressive environments. This study investigates the effects of two heat treatment routes on the microstructure and corrosion resistance of a transformation-induced plasticity (TRIP) steel (Fe-0.2C-1.75Mn-0.5Si-1Al). Route A includes a full austenitizing step at 1000 °C prior to intercritical annealing, whereas Route B omits this step and begins directly with intercritical annealing at 800 °C. Microstructural characterization (SEM/XRD), electrochemical assays, and eddy current tests were employed. The results revealed that Route A yields a homogeneous microstructure with 12.7% retained austenite, …

Centrifugally Spun Silica Fibers For Lithium-Ion Battery Anodes: Structure And Cycling Stability, Alejandra Guerrero, Valeria Tirado, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications

Introduction: Silicon dioxide (SiO2) fiber structures have attracted attention as alternative anode materials for lithium-ion batteries because of their ability to improve cycling stability compared to commercial silicon particles.

Materials and methods: SiO2 composite fibers were prepared by centrifugal spinning of polyvinylpyrrolidone (PVP)/SiO2 precursor solutions followed by calcination at 500–700 ◦C for different holding times to produce short-fiber composites and micro-belt SiO2 fiber structures. The morphology and crystal structure of the SiO2 short fibers and micro-belts were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS). Electrochemical performance was evaluated using CR2032 half-cells.

Results: The …

Optimizing Graphene Oxide In Self-Compacting Concrete: A Sustainable Nano-Material Strategy For Enhanced Durability And Structural Performance, Mohammed Shakeebulla Khan, Vijaya G. S

Journal of Sustainable Construction Materials and Technologies

In order to reduce the environmental impact of the constructed world, advanced and sustainable construction materials are needed. This work is a summary of the comprehensive study on a novel self-compacting concrete with nano-engineered material (graphene oxide) modified self-compacting concrete (GO-SCC). The optimum dosage of GO was determined using Taguchi method, Analysis of Variance (ANOVA) and Response Surface Methodology (RSM) multi-objective statistical optimization method, and was found to be 0.10% by weight of cement (bwoc). This dosage of 0.10% GO led to the overall desirability score of 0.87, which confirmed that this was the optimum dosage for six response variables …

Beneficial Investigation Of Sustainable Recycled Waste Plastic In Treating The Consolidation Behavior Of Fine Soil, Aram Mohammed Raheem, Cumaraswamy Vipulanandan, Mohammed Hiwa Abdullrahman, Ali Tariq Omer

Journal of Sustainable Construction Materials and Technologies

Recycled waste plastic is one of the regular garbage utilized as a sustainable material in soil remediation. This study examines the efficacy of utilizing local recycled waste plastic as an ecological quantifiable along with soil containing fine particles to analyze the consolidation behavior. Various recycled waste plastic contents ranging from 2% to 10% were employed experimentally in two patterns where in the first pattern the recycled waste plastic were mixed as dry material with the fine soil particles while in the second pattern a sandwich layer of 10% of the recycled waste plastic was placed in the middle of the …

Enhanced Thermal Energy Storage In Buildings: Impregnation, Leakage, And Environmental Performance Of Organic And Inorganic Pcm Composites, Gökhan Genç, Esra Yılmaz, M. Yusuf Yazıcı

Journal of Sustainable Construction Materials and Technologies

This study experimentally investigates the impregnation and leakage performance of various organic (tobacco, sawdust, bay leaf, black cumin) and inorganic (vermiculite, perlite, bentonite, sepiolite) carrier materials used for phase change material (PCM) integration in building applications. The commercial paraffin-based PCM RT-31 was used as the thermal storage medium. Impregnation and leakage tests were conducted to evaluate the PCM absorption capacity, form stability, and energy storage potential of each carrier. The results revealed that perlite (C = 80%) and bay leaf (C = 78%) exhibited the highest impregnation capacities due to their porous and fibrous structures; however, they also demonstrated significant …

Modeling Of Tensile Stress-Strain Response For Steel Fiber Reinforced Self-Compacting Concretes, Anıl Niş, Nilufer Özyurt, Turan Özturan

Journal of Sustainable Construction Materials and Technologies

Main aim of the research was to further understand self-compacting concrete reinforced with steel fibers (SFR-SCC) behavior and to contribute modeling of the tensile stress-strain diagrams for the standardization of the fiber reinforced materials for structural utilization. Fiber reinforced materials has not been used without structural rebar because of the absence of stress-strain curve in tension required for the structural design codes. Hence, an inverse analysis (multi-layer model) was further modified for various steel fibers to predict tensile stress-strain behaviour. For this purpose, 5 different mixes; control, reinforced with long fibers with 0.5% and 1%, short fiber with 0.5% and …

The Effect Of Mwcnt-Oil Impregnation Of Sintered Components On Their Wear And Corrosion Resistance, Maha Khaled Abdelfadeel

Theses and Dissertations

Powder Metallurgy (PM) offers an advantageous route for manufacturing complex and near net-shape components. Their inherent interconnected porosity that promotes the action of self lubrication compromises their structural integrity by creating pathways for corrosion and excessive wear. This research investigates the efficacy of Multi-Walled Carbon Nanotubes (MWCNTs) as a nano additive within the impregnating base oil (SN-150 base oil). An experimental matrix was designed to evaluate the influence of MWCNTs with different concentrations of 0.05, 0.1, and 0.2 wt.% and ultrasonic dispersion with varying sonication times of 30 and 60 minutes on the tribological and electrochemical performance of sintered steel …

Rapid-Prototyping Nanofabrication: Lcd-Based Projection Lithography And Physical Vapor Deposition, Sabeel Saleem Mohammmed

University Honors Theses

The semiconductor industry's continued growth, driven in large part by demand for artificial intelligence hardware, has highlighted the need for greater workforce development in regions adjacent to major fabrication centers like Oregon's Silicon Forest. This capstone project lays the groundwork for a small scale and student led semiconductor fabrication lab at Portland State University by demonstrating two of the core steps in chip manufacturing: photolithography and thin film deposition. Rather than relying on conventional fixed reticles, this work explores a unique, low cost approach to patterning that uses an ultraviolet-compatible liquid crystal display (LCD) as a programmable reticle, allowing arbitrary …

Moisture-Induced Degradation And Mechanical Durability Of Mineral-Filled Polylactide (Pla) Composites, Barbara Szaraniec, Aleksandra Ptaszkowska, Alicja Rapacz-Kmita

Journal of Sustainable Construction Materials and Technologies

This study investigates the influence of mineral fillers on the hydrolytic stability and mechanical durability of polylactide (PLA) composites under accelerated aqueous ageing conditions. Composites containing halloysite nanotubes (HNT) and bentonite-based fillers (BM, BS, BSP) at 2 wt.% were prepared using a powder-coating and injection moulding approach. Accelerated hydrolytic degradation was conducted at 50 °C for up to six weeks. The degradation behaviour was evaluated through mass variation, water absorption, incubation medium analysis (pH and electrical conductivity), mechanical testing, surface observations, and contact angle measurements. The results revealed a clear filler-dependent response. Bentonite-filled composites exhibited increased water absorption and accelerated …

Applications Of Geosynthetics In Tunnels Construction: A Sustainable Approach To Carbon Footprint Reduction, Ibraheem Rais, Abdullah H. Alsabhan, Md. Rehan Sadique, Shamshad Alam

Journal of Sustainable Construction Materials and Technologies

The use of geosynthetics has transformed tunnelling practices by enhancing structural integrity, durability, and environmental sustainability. This review adopts a systematic literature review design, covering publications from 2000 to 2025 sourced from Scopus, Web of Science, ScienceDirect, and Google Scholar. The selected studies were screened based on relevance, quality, and focus on tunnelling applications, then thematically analyzed into four domains: geosynthetic types, applications, sustainability, and performance evaluation. This review focuses on the applications of various geosynthetics, including geotextiles, geogrids, geocomposites, geocells, and geomembranes, in tunnelling projects. These materials play crucial roles in reinforcing tunnel walls and slopes, improving load distribution, …

A Generative Ai-Driven Computational Framework For Industry-Scale Discovery Of Novel Battery Materials, Joy Datta

Dissertations

The growing demand for sustainable, high-energy-density electrochemical storage has motivated the exploration of multivalent-ion batteries based on earth-abundant elements such as aluminum, calcium, magnesium, and zinc. While multivalent charge carriers offer higher theoretical energy density than lithium, their practical deployment is hindered by sluggish ion transport, strong ion-host interactions, and structural degradation of electrode materials. Identifying host materials that can reversibly accommodate multivalent ions while maintaining structural integrity remains a fundamental challenge. The dissertation develops a scalable, end-to-end computational framework that integrates density functional theory (DFT), machine learning (ML), and generative artificial intelligence (GenAI) to accelerate the discovery of next-generation …

Electropulse Annealing: Phase Composition Of Tial6v4, Vaughn Eckhardt, Ethan Croke, Ian Baker, Russ Taylor

Wetterhahn Science Symposium Posters

Titanium alloy TiAl6V4 is the most ubiquitous titanium alloy used for dental care, aerospace manufacturing, and for high performance vehicles. The material typically undergoes a thermal heat  treatment, but electropulse annealing is another process that involves sending current through the material to heat it up at a quicker rate. The rate of post-annealing cooling is high, and around the material's critical point, its two components, alpha and beta phase, change in relative concentration. After testing multiple current densities and temperatures, in general, as the current density that the sample received during electropulse annealing decreased, both the alpha and beta phases …

Optimization And Energy Efficiency Analysis Of An Automatic Feed Mixer With A Rotating Drum Mechanism, Kris Witono, Talifatim Machfuroh, Nurlia Pramita Sari, Lisa Agustriyana, Aini Lostari

Journal of Mechanical Engineering Science and Technology (JMEST)

Energy-efficient feed mixer machines are important for improving the productivity and sustainability of small and medium-scale livestock farms. Previous studies primarily focused on either structural performance or mixing efficiency, with limited studies integrating both aspects. Therefore, this study evaluated an automatic rotating-drum feed mixer by combining Finite Element Method (FEM) analysis and energy modeling. The study used FEM simulations for different materials, namely A36 steel alloy, stainless steel 304, aluminium 6061, and galvanized steel, with thicknesses of 3 mm and 4 mm, as well as different drum systems. The FEM results showed that all evaluated materials met the minimum safety …

Influence Of Gas Atmosphere And Deposition Time On Si/Mno₂ Thin Films Properties Deposited By Magnetron Sputtering For Supercapacitor Application, Tansya Trisnatika Dewi, Boon Tong Goh, Reza Akbar Pahlevi, Ishmah Luthfiyah, Markus Diantoro

Journal of Mechanical Engineering Science and Technology (JMEST)

Thin films of MnO₂ were successfully deposited onto Si substrates using the magnetron sputtering technique in various gas atmospheres and deposition times to study their influence on the structural, morphological, electrical, and electrochemical properties for application as supercapacitor electrodes. Structural analysis using XRD showed that deposition under an Ar+O₂ gas atmosphere increased the crystallite size and crystallinity of the Si/MnO₂ films, while shorter deposition times reduced the crystallite size and lowered the crystallinity. Surface morphology observation using SEM showed that the film deposited in an Ar+O₂ gas atmosphere had smaller, more uniform, evenly distributed, and closely …

Influence Of Fiber Loading And Cu/Sio₂ Fillers On Mechanical And Physical Properties Of Sugarcane Bagasse Epoxy Composites, Ansor Salim Siregar, Indra Indra, Agung Fauzi Hanafi, Sunny Ineza Putri

Journal of Mechanical Engineering Science and Technology (JMEST)

The rising worldwide need for lightweight, high-strength, and eco-friendly materials has driven considerable investigation into natural fiber composites. This research offers an extensive examination of the creation and characterization of a new hybrid composite designed for high-performance sports equipment. The composite structure consists of an epoxy matrix strengthened with sugarcane bagasse fibers and synergistic blend of copper and silicon dioxide hybrid particulate fillers. Three unique composite variations were created, with systematically adjusted weight fractions of sugarcane bagasse fiber (35%, 31%, 27%) and hybrid fillers. A thorough assessment of mechanical and physical properties was carried out following ASTM standards. The results …

An Analytical Framework For Quantifying Urban And Community Resilience To Natural Hazards From Cell-Phone Gps-Location And Traffic-Flow Data, Georgios Chatzikyriakidis

Civil and Environmental Engineering Theses and Dissertations

Urban areas are increasingly exposed to natural hazards while accommodating a growing share of the global population, yet a consistent science-based framework for quantifying urban and community resilience remains lacking. This dissertation develops a physics-based analytical framework grounded in statistical mechanics and the quantitative theory of Brownian motion. A city is conceptualized as a complex medium in which citizens move analogously to Brownian particles within a viscoelastic environment, influenced by socioeconomic interactions and infrastructure functionality.

A central premise is that urban resilience, interpreted as engineering resilience (an outcome), can be quantified through a single metric: the mean-square displacement MSD=⟨r²(t)⟩, of …

Sorption And Thermal Conductivity Of Concrete Containing Aggregates Of E-Waste, Rakesh Kumar Saini, Praveen Kumar

Journal of Sustainable Construction Materials and Technologies

In many parts of the world, substantial energy is used to maintain comfortable temperatures in inner parts of the buildings for living and working. Construction materials with low thermal conductivity, if used in the exterior walls and façade etc. in such structures can be useful in lowering the energy demand. On the other hand, moisture ingress through sorption is a common factor contributing in degradation of concrete structures with time. Constituents of concrete may be engineered to some extent to get both the desired attributes, lower thermal conductivity and sorption than normal concrete. The rapid increase in electronic waste, or …

Effects Of Niobium On The Mechanical And Oxidation Properties Of Additively Manufactured Tungsten, Alexander Lesieur, Cayla Eckley, Ryan A. Kemnitz

Faculty Publications

Although additive manufacturing presents a novel and customizable approach to fabricating tungsten (W) alloys, the layer-by-layer production technique presents a unique set of processing challenges which are further exacerbated by the metal’s refractory properties. In this study, additions of niobium (Nb) were found to improve the mechanical properties and oxidation resistance of additively manufactured W. Microstructural investigation revealed the effect of Nb on the cracking, grain size, and texture in the as-built material. Mechanical compression testing showed significant improvement in ductility with increasing Nb content. The low concentrations of Nb used did not induce large changes in the yield strength …

Thermal Transient Analysis Of Mahogany Wood Biomass Pyrolysis: The Role Of Zeolite Catalyst Variations On Temperature Distribution, Yusri Yusri, Widya Wijayanti, Mega Nur Sasongko

Journal of Mechanical Engineering Science and Technology (JMEST)

Biomass pyrolysis is a thermochemical process that converts waste into fuel. The use of zeolite catalysts can enhance efficiency by accelerating biomass decomposition. To demonstrate its effect, thermal simulations were conducted using ANSYS Thermal Transient to analyze temperature distribution, reaction rates, and catalyst effectiveness in the pyrolysis process. This study aims to improve thermal efficiency and temperature uniformity by analyzing the effect of 10% and 20% zeolite mixtures on heat distribution and heating rates at input temperatures of 650 K, 750 K, and 850 K, using the 2D axial symmetry method. The simulation was performed under specific boundary conditions: input …

Plastic Material Analysis And Bonding In Small Aquatic Vessels, Andrew R. Orr

Honors College Theses

This project presents the design and development of a suitable vessel for small-scale aquatic applications. The developed project is used for a remote-controlled duck hunting system, and the parameters of the design are based on the requirements for the system as a whole. Traditionally, plastics are fabricated using blow molding to create a single seamless form. However, for small-scale prototyping with limited resources, this method of fabrication is unsustainable for short-term, non-industrial design applications. As a result, an existing longer hull is selected and shortened to meet the required project length. The project evaluates multiple initial hull designs, ultimately selecting …

Ballistics Characterization Of Micro-Truss Reinforced Lunar-Inspired Geopolymer Concrete For Space Construction, Phoebe G. Johnson

Honors Theses

This research investigates the ballistics response and compressive strength of a Fly Ash/ Lunar Regolith hybrid geopolymer concrete developed for space construction. The study aimed firstly to optimize the Fly Ash/ Regolith mix ratio for maximum mechanical performance and secondly, to evaluate the effectiveness of carbon-fiber micro-truss reinforcement, produced by 3D printing, in mitigating damage from high-velocity impacts. Concrete specimens with varying Fly Ash-to-Regolith ratios (100-50% Fly Ash) were fabricated and tested under compression and ballistic loading. Compressive strength tests followed ASTM C109 using a 110 Kip 810-MTS testing apparatus on both unreinforced and reinforced 2” cubes. For unreinforced samples, …

Brine Solidification And Metals Sequestration Using Lignocellulosics, Frank Kvietok

World of Coal Ash Proceedings

Coal ash has historically been used as a convenient, on-site solidification material for brines generated from flue gas desulfurization at power plants. As alternate utilization scenarios are developed for coal ash, lignocellulosic (wood-based) sorbents can serve as a highly efficient substitute for the solidification process. Results will be shared for a variety of different brine types: thermally reduced, thermally reduced and neutralized, and reverse osmosis. In addition to solidification performance, which demonstrated a 3-4x mass of liquid vs mass of sorbent factor, studies were conducted to quantify the strength of binding to the wood-based sorbent for a broad range of …

Practical Guidelines For Pump Testing Of Ccr: Workflow, Design, And Lessons Learned., Nathanial Keller, Brian Hennings, Vic Modeer, Katie Moran

World of Coal Ash Proceedings

This session presents a streamlined approach for pump testing of coal combustion residuals (CCR) to maximize hydraulic information with limited well installations, variable pumping rates, and short tests. Pre-test forward modeling identifies well offsets (typically 5–10 ft) and test durations (~2–6 hours) to yield measurable and analyzable drawdown at observation wells despite low pumping rates. Field execution consists of short step-drawdown testing to evaluate well specific capacity and select pumping rates for a constant rate test with one or more observation wells. Test results facilitate analysis of transmissivity and storativity of the CCR. Applied at two Midwestern sites with different …

Simplified Approximate Procedure For Assessing The Implications Of Updated Usgs Seismic Hazard Models On Seismic Stability Assessments Of Ccr Impoundment Facilities, Nick Mcclung, Matt Bishop, Adrian Pena-Iguaran, Seda Gokyer-Erbis

World of Coal Ash Proceedings

Selection of appropriate seismic design ground motions remains a key challenge for seismic stability assessments of coal combustion residual (CCR) impoundment facilities, particularly where regulatory guidance does not specify a required hazard model. This paper examines the implications of using Uniform Hazard Spectra (UHS) derived from the 2014 versus the 2018 U.S. Geological Survey (USGS) National Seismic Hazard Model (NSHM) for seismic amplification and stability evaluations of the Tennessee Valley Authority (TVA) Widows Creek Fossil (WCF) Plant CCR Management Units. The 2018 NSHM incorporates updated understanding of seismicity in the central and eastern United States and generally predicts higher ground …

Before The Limit Hits: Lessons From A Proactive Construction Air Monitoring Program, Brian Egan, Nicholas Golden, Wendy Depp

World of Coal Ash Proceedings

This presentation describes a comprehensive air monitoring program designed to protect workers and nearby neighborhoods during ash pond closure work. The program uses three main components: project (or boundary) monitoring at the site perimeter to track dust near the project boundaries, work area monitoring placed near active construction zones, and personal sampling on individual workers at regular intervals. Together, these approaches provide data on both community impacts and worker exposures, helping the team respond quickly when levels approach action limits. The Teams actions prior to exceedance of regulatory limits has helped prevent exposures. The talk will explain how monitors are …

Integrating Advanced Geochemical Workflows With Modern Statistical Tools To Improve The Decision-Making Process At Ccr Sites, A Case Study, Glenna Thomas

World of Coal Ash Proceedings

While statistical assessment provides the foundation for CCR compliance reporting, incorporating a holistic geochemical framework transforms statistics from a compliance requirement into a powerful predictive tool. Strategic geochemical insight established the basis of understanding needed to support successful statistical approaches and to ensure that statistical outcomes reflect actual groundwater behavior. Whether it is trend analysis, delineating source mechanism, or updating geochemical conceptual site models (GCMs), geochemical context provides the technical foundations for statistical outputs and methods. A continuously refined GCSM enhances the ability to anticipate how groundwater chemistry should evolve, improving interpretation and predictive capability. This allows practitioners to understand …

Establishing Groundwater Monitoring Systems Under The Legacy Rule: A Systematic Approach For Utilities, Chris Hoglund

World of Coal Ash Proceedings

The USEPA’s Legacy CCR Rule introduces new requirements for establishing groundwater monitoring systems at Legacy Surface Impoundments (LSIs) and Coal Combustion Residual Management Units (CCRMUs). These requirements present unique challenges for electric utilities, particularly at inactive or historically operated facilities where subsurface data are limited and CCR units may have nontraditional configurations such as linear roadways, elongated embankments, or distributed disposal areas. Utilities must also determine how best to apply single-unit or multi-unit monitoring approaches, integrate newly regulated units into existing monitoring networks, and align monitoring system design with planned closure strategies. This presentation outlines a systematic, defensible framework to …

Risk Evaluation Of Linear Coal Combustion Residual Management Unit (Ccrmu) Fills, Qian Zhang, Andrew Bittner, John Kondziolka, Masoud Arshadi

World of Coal Ash Proceedings

In 2024, the US Environmental Protection Agency (US EPA) established new regulations for coal combustion residual management units (CCRMUs), defined as coal combustion residual (CCR) deposits placed on power plant properties outside of landfills or surface impoundments. US EPA supported the rulemaking with modeling-based risk analyses and established regulatory requirements based on fill size. Linear CCRMU, such as backfill along pipelines or haul roads, have individual segments that may be composed of a small amount of mass below the threshold for regulation, but the cumulative mass over the full linear feature extent may exceed regulatory thresholds. This study applies US …

Application Of Mine Tailings Flow Failure Assessment On Ccr, Zachary Fallert

World of Coal Ash Proceedings

A new geotechnical stability analysis method has been implemented for a CCR surface impoundment to aid in design for temporary cut slopes and final closure grades. Conditions have come to light after significant tailings dam failures occurred across the globe, specifically those exhibiting flow failures (i.e. failures in which tailings behave a liquid and flow out of the facility). These failures have come under intense scrutiny as the failures pose significant risk to public safety and the environment and have been observed in CCR. Additionally, static liquefaction has arisen as another potential but less well understood causative mechanism. As the …