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Materials Science and Engineering Faculty Research & Creative Works

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Full-Text Articles in Materials Science and Engineering

Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy, Agustin Morales-Aragon, Daniel Sánchez-Rodas, Guillermo Ríos, Michael S. Moats Feb 2025

Impurity Behavior In Cast Copper Anodes: Implications For Electrorefining In A Circular Economy, Agustin Morales-Aragon, Daniel Sánchez-Rodas, Guillermo Ríos, Michael S. Moats

Materials Science and Engineering Faculty Research & Creative Works

The behavior of impurities in cast copper was investigated to simulate production with increased utilization of secondary sources within the framework of a circular economy. The incorporation of impurities, particularly Ni, Sn, and Sb, from recycled Cu may significantly impact the electrorefining process. In this study, commercial anodes were doped with Ni, Sn, and Sb concentrations of 2500–6500 g/t, 300–900 g/t, and 450–950 g/t, respectively. Anode concentrations of Pb and Bi were maintained at 1000 g/t and 350 g/t, respectively. As concentrations were examined at two levels, 860 or 1700 g/t, depending on the commercial anode used to create the …

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Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types, Sahil Surehali, Collin Gustafson, Sayee Srikarah Volaity, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath Feb 2025

Rheology And Early-Age Structure Development In Binary And Ternary Blends Modified With Novel Graphene Types, Sahil Surehali, Collin Gustafson, Sayee Srikarah Volaity, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Interest in the use of graphene to enhance the properties of cementitious materials is growing, but major impediments in implementation are the cost of graphene and changes in binder rheology attributable to these nanomaterials. This study explores the influence of novel, cost-effective, environment-friendly, and mass-producible graphene on the rheology and early-age structure development of cementitious binders. Two novel graphene types—fractal graphene (FG) and reactive graphene (RG)—are used in plain cement mixtures as well as those containing 30 % (by mass) of fly ash and/or limestone powder, at low dosages of ≤0.02 % by mass of binder. The early- and later-age …

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Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement, Sai Akshay Ponduru, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Narayanan Neithalath, Gaurav Sant, Aditya Kumar Feb 2025

Effects Of Gypsum And Limestone On Early-Age Hydration And Strength Optimization In Belite Calcium Sulfoaluminate Cement, Sai Akshay Ponduru, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Narayanan Neithalath, Gaurav Sant, Aditya Kumar

Materials Science and Engineering Faculty Research & Creative Works

Belite calcium sulfoaluminate cement (CSAB), an alternative to Portland cement, exhibits excellent strength at both early and later ages. However, due to its high belite content, the carbon reduction from this type of cement is not sufficient when compared to other alternative cements. To further enhance CSAB's sustainability, this study investigates the performance of CSAB when partially replaced by low-carbon mineral additives (i.e., limestone and gypsum). The primary objective is to identify the optimal mixture design by incorporating gypsum and limestone to formulate a sustainable binder that maintains high compressive strength. The CSAB is replaced (with both additives) by up …

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Spark Plasma Sintering Of (Zr,Nb)C Ceramics, Jacob Stacy, Greg Hilmas, Jeremy Watts, Brian Taylor, Jhonathan Rosales Jan 2025

Spark Plasma Sintering Of (Zr,Nb)C Ceramics, Jacob Stacy, Greg Hilmas, Jeremy Watts, Brian Taylor, Jhonathan Rosales

Materials Science and Engineering Faculty Research & Creative Works

A range of (Zr,Nb)C ceramics containing 20–50 vol% NbC were spark plasma sintered at 2000°C. The ceramics had relative densities greater than 97 %, and all compositions formed a complete solid solution. The average grain size was ∼7.1 µm over all compositions. Elastic moduli values ranged from 436 to 445 GPa, and the fracture toughness ranged from 0.8 to 2.8 MPa·m1/2 over the compositional range, both increasing with increasing NbC content. The hardnesses of the (Zr,Nb)C ceramics ranged from 19.1 to 20.2 GPa at a load of 9.81 N. The flexural strength increased from 352 to 395 MPa as the …

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Designing Robust Quasi-2d Perovskites Thin Films For Stable Light-Emitting Applications, Sharmistha Khan, Reshna Shrestha, Mengru Jin, Doyun Kim, Guan Lin Chen, Ruipeng Li, Yijia Gu, Qing Tu, Namyoung Ahn, Wanyi Nie Jan 2025

Designing Robust Quasi-2d Perovskites Thin Films For Stable Light-Emitting Applications, Sharmistha Khan, Reshna Shrestha, Mengru Jin, Doyun Kim, Guan Lin Chen, Ruipeng Li, Yijia Gu, Qing Tu, Namyoung Ahn, Wanyi Nie

Materials Science and Engineering Faculty Research & Creative Works

Quasi-2D perovskite made with organic spacers co-crystallized with inorganic cesium lead bromide inorganics is demonstrated for near unity photoluminescence quantum yield at room temperature. However, light emitting diodes made with quasi-2D perovskites rapidly degrade which remains a major bottleneck in this field. In this work, It is shown that the bright emission originates from finely tuned multi-component 2D nano-crystalline phases that are thermodynamically unstable. The bright emission is extremely sensitive to external stimuli and the emission quickly dims away upon heating. After a detailed analysis of their optical and morphological properties, the degradation is attributed to 2D phase redistribution associated …

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A Novel Technique For Improved Measurement Of Graphite And Inclusions In Ductile Iron Contaminated By Boron, Chase Schroeder, Colleen Lehrer, Simon Lekakh, Laura Bartlett Jan 2025

A Novel Technique For Improved Measurement Of Graphite And Inclusions In Ductile Iron Contaminated By Boron, Chase Schroeder, Colleen Lehrer, Simon Lekakh, Laura Bartlett

Materials Science and Engineering Faculty Research & Creative Works

The highly heterogeneous microstructure of ductile iron in casting includes graphite particles, non-metallic inclusions, microporosity, and other features, such as carbides distributed in the ferrite–pearlite matrix. Determination and comprehensive quantification of microstructural features are practically important however challenging. An advanced methodology based on an automated SEM/EDX analysis was developed and compared to the standard optical imaging method. In addition to backscattered electron contrast, sensitive to atomic number, a novel methodology added EDX data to identify and classify the multiple structural features at micron resolution thresholding. To quantify the shape of individual phases, the eight chord raster algorithms was used and …

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Evaluation Of Processing Conditions For The Reduction Of Electrochemical Salt Waste Using Phosphate-Based Dechlorination, Harmony Werth, Jade Beland, Paige Murray, Dave Liang, Laurel Sharpless, Jonathan Evarts, Charmayne Lonergan, Brian J. Riley, Michael Simpson, Krista Carlson Jan 2025

Evaluation Of Processing Conditions For The Reduction Of Electrochemical Salt Waste Using Phosphate-Based Dechlorination, Harmony Werth, Jade Beland, Paige Murray, Dave Liang, Laurel Sharpless, Jonathan Evarts, Charmayne Lonergan, Brian J. Riley, Michael Simpson, Krista Carlson

Materials Science and Engineering Faculty Research & Creative Works

Electrochemical processing of used nuclear fuel in molten chloride salts generates complex radioactive salt waste. Dechlorination of waste salt using phosphate compounds at elevated temperatures (∼600 °C) reduces the volume of material for disposal while evolving gaseous chlorine compounds that could be used to transform metallic uranium into UCl3. In this study, the effects of processing temperature, environment (air or argon), and H3PO4 precursor-to-chlorine ratio on the dechlorination efficacy of a simple alkali salt mixture (SSM) and a salt waste simulant (ERV3) were evaluated. For both salts, the highest chlorine release was concurrent with the water boiling. For the SSM, …

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Hydrogen Permeation In Iron-Chromium-Aluminum (Fecral) Alloys And The Effects Of Microstructure And Surface Oxide, Nathan T. Gehmlich, Thomas F. Fuerst, Hanns Gietl, Chase N. Taylor, Joshua Rittenhouse, Haiming Wen, M. Nedim Cinbiz Jan 2025

Hydrogen Permeation In Iron-Chromium-Aluminum (Fecral) Alloys And The Effects Of Microstructure And Surface Oxide, Nathan T. Gehmlich, Thomas F. Fuerst, Hanns Gietl, Chase N. Taylor, Joshua Rittenhouse, Haiming Wen, M. Nedim Cinbiz

Materials Science and Engineering Faculty Research & Creative Works

Iron–chromium–aluminum (FeCrAl) class alloys are candidates for use as cladding for accident-tolerant fuels and moderators. In this context, hydrogen isotope permeation in FeCrAl alloys is an important material property. In the present work, the apparent permeability, effective diffusivity, and apparent solubility of hydrogen in the FeCrAl alloys C26M and Kanthal D (KD) were measured with gas-driven hydrogen permeation. Permeation measurements were conducted at temperatures of 400 to 700 °C and at gas-driven pressures from 1 to 100 kPa. In particular, the effect of grain size on hydrogen transport was studied with KD samples with three different microstructures: nanocrystalline (NC), ultra-fine …

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Dual-Bed Radioiodine Capture From Complex Gas Streams With Zeolites: Regeneration And Reuse Of Primary Sorbent Beds For Sustainable Waste Management, Krista Carlson, Brian J. Riley, Joshua Turner, David C. Cantu, Dev Chidambaram, Charmayne Lonergan, Jeffrey D. Rimer Jan 2025

Dual-Bed Radioiodine Capture From Complex Gas Streams With Zeolites: Regeneration And Reuse Of Primary Sorbent Beds For Sustainable Waste Management, Krista Carlson, Brian J. Riley, Joshua Turner, David C. Cantu, Dev Chidambaram, Charmayne Lonergan, Jeffrey D. Rimer

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

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Degradation Of Radioactive Waste Encapsulation Of Bao−Feox−P2o5 Glass Evaluated From Electrical Conductivity, Kazuki Mitsui, Nobuyasu Nishioka, Hiromichi Takebe, Richard K. Brow, Akira Saitoh Jan 2025

Degradation Of Radioactive Waste Encapsulation Of Bao−Feox−P2o5 Glass Evaluated From Electrical Conductivity, Kazuki Mitsui, Nobuyasu Nishioka, Hiromichi Takebe, Richard K. Brow, Akira Saitoh

Materials Science and Engineering Faculty Research & Creative Works

We report on the electrical conductivity of barium iron phosphate glass, a candidate for radioactive waste encapsulating glass. The glass composition has been optimized for slow dissolution in hot water because the precipitation of a stable hydration layer of FeO(OH) on the glass surface enhances the water durability of the glass. The mechanism of electrical conductivity of the glass is assumed to be an electron hopping between the electronic energy levels of Fe (II) and Fe (III) ions, obeying the electron carrier generation of Fe (II) → Fe (III) + e−. The electrical conductivity of the base glass was ∼3.2 …

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Understanding Heterogeneous Nucleation In Iron Alloys From First Principles: A Review And Discussion, Semen Naumovich Lekakh Jan 2025

Understanding Heterogeneous Nucleation In Iron Alloys From First Principles: A Review And Discussion, Semen Naumovich Lekakh

Materials Science and Engineering Faculty Research & Creative Works

Heterogeneous nucleation during solidification plays a key role in structure formation of different types of iron-based alloys, including steels and cast irons. A review summarizes the novel theoretical methods which were used to understand the nature of heterogeneous nucleation in iron-based alloys. An ab initio simulation of atomic adsorption was used to predict the activity of heterogeneous nuclei, and the thermodynamic methods were applied to design conditions for desired precipitate formation in the iron melts. A high-resolution TEM study of individual nucleus and statistics of nuclei family, obtained from an automated SEM/EDX analysis, illustrates a possibility to design processes of …

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Ground Testing Of A Magnetic-Electrostatic Separation System For Lunar Regolith Beneficiation, Peter Bachle, Charles Wood, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han Jan 2025

Ground Testing Of A Magnetic-Electrostatic Separation System For Lunar Regolith Beneficiation, Peter Bachle, Charles Wood, Jeffrey Smith, Fateme Rezaei, David Bayless, William Schonberg, Daoru Han

Materials Science and Engineering Faculty Research & Creative Works

The separation of lunar regolith by mineral composition and size category is useful forin-situ resource utilization (ISRU). The research presented herein discusses the designing and development of equipment that has the potential to separate lunar regolith into aluminum, iron-titanium, and magnesium-iron ores. Along with the metal ore separation, this equipment shows the potential to separate regolith by size categories. The combined effect of these separation methods generates output that is valuable to subsequent use in metal and oxygen extraction, additive manufacturing, and regolith sintering processes. The designed equipment uses a dual-strength magnet system with N42 and N52 neodymium magnets for …

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The Effect Of Carbon Equivalent And Nodularity On Multi-Axial Casting Wall Movement During Spheroidal Graphite Iron Solidification And Cooling, Noah J. Brack, Mingzhi Xu, Jingjing Qing, Simon Lekakh Jan 2025

The Effect Of Carbon Equivalent And Nodularity On Multi-Axial Casting Wall Movement During Spheroidal Graphite Iron Solidification And Cooling, Noah J. Brack, Mingzhi Xu, Jingjing Qing, Simon Lekakh

Materials Science and Engineering Faculty Research & Creative Works

Spheroidal graphite iron, also known as ductile iron, is an iron–carbon casting alloy used in industry for its good castability, balanced mechanical properties, and low cost. Ductile iron consists of round graphite nodules in an iron matrix. During solidification and cooling, ductile iron castings experience dynamic volume changes due to the precipitation of graphite nodules and formation of austenite. These dynamic volume changes can distort external casting surfaces, causing swell and shrinkage porosity. A novel apparatus was custom-built to capture the casting wall movement in real time along three axes. This study found that casting expansion increased with carbon equivalent …

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Controlling Nitrogen Pickup During Induction Melting Of Ultrahigh-Strength Cr-Ni-Mo-V Steels, Kingsley T. Amatanweze, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field Jan 2025

Controlling Nitrogen Pickup During Induction Melting Of Ultrahigh-Strength Cr-Ni-Mo-V Steels, Kingsley T. Amatanweze, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field

Materials Science and Engineering Faculty Research & Creative Works

Nitrogen pickup during air induction melting can result in porosity and a loss of fracture toughness in ultrahigh-strength quenched and tempered steel castings. Nitrogen atoms are easily adsorbed into liquid steel upon exposure to the air, and argon shrouding alone has limited effectiveness. Previous studies have shown that proper charge sequencing and maintaining a high amount of dissolved oxygen in the melt prior to tapping and deoxidation can limit nitrogen pickup in the melt. In the current study, the effect of melt practice and charging procedure on nitrogen pickup was studied as a function of hold time in a series …

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Zrc Particle Size Effect On The Mechanical Properties Of Spark Plasma Sintered 60–40 Vol% Zrc–Mo Cermets, Nathaniel Blatt, Jeremy Watts, Brian Taylor, Jhonathan Rosales, Gregory Hilmas Jan 2025

Zrc Particle Size Effect On The Mechanical Properties Of Spark Plasma Sintered 60–40 Vol% Zrc–Mo Cermets, Nathaniel Blatt, Jeremy Watts, Brian Taylor, Jhonathan Rosales, Gregory Hilmas

Materials Science and Engineering Faculty Research & Creative Works

Cermet's of 60 vol% ZrC and 40 vol% Mo with different starting ZrC particle sizes were spark plasma sintered to full density at 1950 °C. Elastic moduli, Vickers hardness and fracture toughness were measured at room temperature and flexural strength was measured up to 1600 °C. Young's modulus was 365 ± 5 GPa, shear modulus was 149 ± 2 GPa, Poisson's ratio was 0.22 ± 0.01, and no significant difference was observed for the moduli with respect to the starting ZrC particle size. Room temperature flexural strength was affected by the ZrC particle size, measured as ∼524 and ∼598 MPa …

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Parametric Analysis Of Water Jet Descaling Efficiency Of Reheated Continuously Cast Thin Slab, Tochukwu P. Ojiako, Mario F. Buchely, Simon Lekakh, Ronald J. O'Malley, Richard Osei, Taha Tayebali Jan 2025

Parametric Analysis Of Water Jet Descaling Efficiency Of Reheated Continuously Cast Thin Slab, Tochukwu P. Ojiako, Mario F. Buchely, Simon Lekakh, Ronald J. O'Malley, Richard Osei, Taha Tayebali

Materials Science and Engineering Faculty Research & Creative Works

Efficient oxide scale removal is critical for maintaining surface quality and process efficiency in steel manufacturing. This study optimizes water jet descaling by evaluating the performance of flat and rotary jet nozzles under varying process parameters. Using a combined approach of experimental analysis and computational fluid dynamics, it investigates the influence of pressure (138–275 bar), lead angle (0°, 15°, 25°), working distance (50–100 mm), and spray angle (15°–25°) on descaling efficiency. Findings indicate that flat jet nozzles achieve superior performance at short working distances due to concentrated impact forces, while rotary jet nozzles sustain efficiency over extended distances through dynamic …

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Effect Of Gating Design On Filling And Inclusion Control In An Al-Killed Cr-Mo-Ni Steel, Kingsley T. Amatanweze, Koushik Balasubramanian, Soumava Chakraborty, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field, Krista R. Limmer, Katherine M. Sebeck Jan 2025

Effect Of Gating Design On Filling And Inclusion Control In An Al-Killed Cr-Mo-Ni Steel, Kingsley T. Amatanweze, Koushik Balasubramanian, Soumava Chakraborty, Viraj A. Athavale, Mario F. Buchely, Laura N. Bartlett, Ronald J. O'Malley, Daniel M. Field, Krista R. Limmer, Katherine M. Sebeck

Materials Science and Engineering Faculty Research & Creative Works

The effect of gating system design on the inclusion population and size distribution in an aluminum-killed low-alloy advanced high strength steel casting was studied. A mold with four different gating systems: pressurized and non-pressurized with side risers, naturally pressurized with a side riser, and naturally pressurized with a top riser, was designed using computational fluid dynamics and solidification software. The design allowed inclusion populations in castings produced with each gating system to be compared during the same pouring event. Samples taken from different positions just below the top surface of each casting were analyzed using an SEM/EDS system with automated …

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High-Temperature Performance Of Alloyed Cast Irons And Cr/Ni Austenitic Steels—An Overview And Discussion, Simon N. Lekakh, Mei Li, Larry Godlewski Jan 2025

High-Temperature Performance Of Alloyed Cast Irons And Cr/Ni Austenitic Steels—An Overview And Discussion, Simon N. Lekakh, Mei Li, Larry Godlewski

Materials Science and Engineering Faculty Research & Creative Works

Fe-based cast alloys, including cast irons and steels, have been used in service at a wide range of mechanical and thermal load in oxidizing environment. Special alloying practices can be used to improve high temperature performance of Fe-based cast alloys in an oxidizing atmosphere. At elevated temperatures, alloying elements can produce a protective interface layer which prevents oxidant penetration into the metal matrix. However, a combination of thermo-mechanical loads along with surface oxidation can decrease the materials integrity by destroying the stable protected interface limiting the range of working parameters and lifetime performance of the material. This overview aims to …

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Ultrafast Belite (Β-C2s) Production Using Biofuel-Based Combustion Synthesis, Shubham Agrawal, Sayee Srikarah Volaity, Oluwadamilare Charles Adesina, Bryan K. Aylas-Paredes, Taihao Han, Srinivas Kilambi, Aditya Kumar, Narayanan Neithalath Jan 2025

Ultrafast Belite (Β-C2s) Production Using Biofuel-Based Combustion Synthesis, Shubham Agrawal, Sayee Srikarah Volaity, Oluwadamilare Charles Adesina, Bryan K. Aylas-Paredes, Taihao Han, Srinivas Kilambi, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

This study presents a novel low-temperature, combustion synthesis (CS) approach for the rapid production of belite-rich cements. CS leverages the exothermic heat released from the combustion of biofuels such as lignin and/or biomass, intermixed with pelletized limestone and quartz. At an imposed furnace temperature of ∼700°C (as opposed to 1200°C–1300°C required in a conventional kiln), the source materials are rapidly transformed to belite, resulting in energy, emissions, and economic benefits. This work explores the influence of various process parameters, viz., fuel types and contents, airflow rate, porosity, holding temperature, and holding time on the efficiency of CS-based belite synthesis. Through …

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Flexural Strength Of (Hf,Nb,Ta,Ti,Zr)B2–(Hf,Nb,Ta,Ti,Zr)C High-Entropy Dual-Phase Ceramics, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas, Jeremy Watts Jan 2025

Flexural Strength Of (Hf,Nb,Ta,Ti,Zr)B2–(Hf,Nb,Ta,Ti,Zr)C High-Entropy Dual-Phase Ceramics, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas, Jeremy Watts

Materials Science and Engineering Faculty Research & Creative Works

The room and elevated temperature flexural strengths were measured for (Hf,Nb,Ta,Ti,Zr)B2–(Hf,Nb,Ta,Ti,Zr)C high-entropy dual-phase ceramics. The fracture of ceramics originated from two distinct flaw populations that were either surface defects introduced during specimen preparation or volume defects introduced during processing. The average strength at room temperature was 638 ± 94 MPa with individual bars strengths as high as ∼800 MPa. At 1800°C, average strength increased to 786 ± 265 MPa with individual bar strengths as high as ∼1050 MPa. Above 1800°C, creep dominated resulting in deformation of the bars without fracture. The fracture mode changed from completely trans granular at room …

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Roadmap To 100 Gwdc: Scientific And Supply Chain Challenges For Cdte Photovoltaics, B. Edward Sartor, Samantha B. Reese, Lorelle M. Mansfield, Ryan Muzzio, Chun Sheng Jiang, Eric Colegrove, John S. Mangum, Camden L. Kasik, Daniel Z. Shaw, James R. Sites, Ramesh G. Dhere, Alex B. Goldstone, Michael S. Moats Jan 2025

Roadmap To 100 Gwdc: Scientific And Supply Chain Challenges For Cdte Photovoltaics, B. Edward Sartor, Samantha B. Reese, Lorelle M. Mansfield, Ryan Muzzio, Chun Sheng Jiang, Eric Colegrove, John S. Mangum, Camden L. Kasik, Daniel Z. Shaw, James R. Sites, Ramesh G. Dhere, Alex B. Goldstone, Michael S. Moats

Materials Science and Engineering Faculty Research & Creative Works

This roadmap highlights pathways to expand the CdTe module manufacturing capacity per year to 100 GWDC by 2030 by improving Te extraction from existing supply chains, minimizing Te usage in modules by leveraging thinner absorbers, and focusing research efforts in key areas to improve module efficiencies. Both scientific and supply chain innovations will be necessary to maintain the high compound annual growth rate of the CdTe photovoltaic (PV) industry and cement its role as a key technology for multi-TW-scale PV deployment.

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High-Frequency Gold Price Forecasting: Optimizing Multi-Layer Perceptron With Genetic Algorithm, Vrtagic Sabahudin, Fatih Dogan Dec 2024

High-Frequency Gold Price Forecasting: Optimizing Multi-Layer Perceptron With Genetic Algorithm, Vrtagic Sabahudin, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Accurately forecasting gold price actions is critical in financial markets due to gold's role as a safe-haven asset. This paper addresses the challenge of forecasting gold prices by applying a Genetic Algorithm (GA) with a Multi-Layer Perceptron (MLP) model. The research exploits historical financial data from various instruments, including gold futures, Bitcoin, and key currency pairs, to improve prediction accuracy. By optimizing the MLP's hyper parameters through GA, the model efficiently captures complex relationships in high-frequency data, achieving a remarkable R² score of 0.9993. This level of precision demonstrates the model's potential for providing actionable insights for traders and investors. …

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Complex Precipitation Behavior In A Co-Free High Entropy Alloy During Aging, Matthew Luebbe, Fan Zhang, Jonathan D. Poplawsky, Jiaqi Duan, Haiming Wen Dec 2024

Complex Precipitation Behavior In A Co-Free High Entropy Alloy During Aging, Matthew Luebbe, Fan Zhang, Jonathan D. Poplawsky, Jiaqi Duan, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

High entropy alloys (HEAs) demonstrate high strength, thermal stability, and irradiation resistance, making them desirable for applications in nuclear reactors and other harsh environments. Many existing HEAs contain cobalt (Co), which makes them unsuitable for nuclear applications due to the long-term activation of Co. A previously studied Co-free alloy, (Fe0.3Ni0.3Mn0.3Cr0.1)88Ti4Al8, exhibits high strength but compromised ductility due to its network of brittle precipitates upon aging. This work investigates the formation mechanism and evolution of the precipitates, including L12 (Ni3Ti type, ordered face-centered cubic …

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Multiphysics Modeling And Experimental Validation Of High-Strength Steel In Laser Powder Bed Fusion Process, M. Rangapuram, S. Babalola, J. W. Newkirk, L. N. Bartlett, F. W. Liou, K. Chandrashekhara, Stephen R. Cluff Dec 2024

Multiphysics Modeling And Experimental Validation Of High-Strength Steel In Laser Powder Bed Fusion Process, M. Rangapuram, S. Babalola, J. W. Newkirk, L. N. Bartlett, F. W. Liou, K. Chandrashekhara, Stephen R. Cluff

Materials Science and Engineering Faculty Research & Creative Works

Laser powder bed fusion (LPBF) is a subset of the additive manufacturing process in which a laser beam selectively joins the metal powder into a desired part in a sequential layer process. Owing to its complex nature of rapid heating and cooling of the melt pool, there is a need to understand the melt pool behavior and its effects on the final manufactured part. a densely packed powder bed is highly desirable for fabricating a superior part using the LPBF process. in this work, discrete element model was used to generate powder beds with realistic powder properties and various factors …

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Estimating The Possible Qpos Of M87* From The Parameters Of A Hairy Kerr Black Hole, Orhan Donmez, Fatih Dogan Dec 2024

Estimating The Possible Qpos Of M87* From The Parameters Of A Hairy Kerr Black Hole, Orhan Donmez, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

In this paper, we study the dynamics of the shock cone formed around a hairy Kerr black hole due to Bondi– Hoyle–Lyttleton (BHL) accretion and investigate the quasi-periodic oscillations (QPO) behaviors resulting from the black hole-cone interaction, aiming to predict the QPO frequencies that may occur around the M87∗ black hole. To achieve this, we use the hairy Kerr black hole parameters consistent with the observed shadow parameters of M87∗ as initial conditions in numerical simulations, revealing the structure of the resulting shock cone and QPOs in a strong gravitational field. Numerical calculations show that the deviation of …

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Hafnium Oxide Coating To Improve The Oxidation Behavior Of Zirconium Diboride, Jan E. Förster, William G. Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju Dec 2024

Hafnium Oxide Coating To Improve The Oxidation Behavior Of Zirconium Diboride, Jan E. Förster, William G. Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju

Materials Science and Engineering Faculty Research & Creative Works

Hafnium dioxide (HfO2) coatings were successfully deposited on zirconium diboride (ZrB2) using reactive magnetron sputtering. After the oxidation at 1500°C or 1600°C, the mutual dissolution of HfO2 and thermally grown ZrO2 was observed which has resulted in the formation of a mixed oxide zone. As the enrichment of the mixed oxide zone by ZrO2 progresses, monoclinic/tetragonal phase transition temperature of ∼1790°C for nominally pure HfO2 moves towards ∼1500 °C. Finally, the inevitable phase transition from monoclinic to tetragonal structure results in the development of cracks, pores, and gaps within the mixed oxide …

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Machine Learned Interatomic Potentials For Ternary Carbides Trained On The Aflow Database, Josiah Roberts, Biswas Rijal, Simon Divilov, Jon Paul Maria, William G. Fahrenholtz, Douglas E. Wolfe, Donald W. Brenner, Stefano Curtarolo, Eva Zurek Dec 2024

Machine Learned Interatomic Potentials For Ternary Carbides Trained On The Aflow Database, Josiah Roberts, Biswas Rijal, Simon Divilov, Jon Paul Maria, William G. Fahrenholtz, Douglas E. Wolfe, Donald W. Brenner, Stefano Curtarolo, Eva Zurek

Materials Science and Engineering Faculty Research & Creative Works

Large-density functional theory (DFT) databases are a treasure trove of energies, forces, and stresses that can be used to train machine-learned interatomic potentials for atomistic modeling. Herein, we employ structural relaxations from the AFLOW database to train moment tensor potentials (MTPs) for four carbide systems: CHfTa, CHfZr, CMoW, and CTaTi. The resulting MTPs are used to relax ~6300 random symmetric structures and are subsequently improved via active learning to generate robust potentials (RP) that can relax a wide variety of structures, and accurate potentials (AP) designed for the relaxation of low-energy systems. This protocol is shown to yield convex hulls …

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A General Model For The Ductility Of Intermetallics Applied To Fe-Co Alloys, Wesley Everhart, Joseph Newkirk Dec 2024

A General Model For The Ductility Of Intermetallics Applied To Fe-Co Alloys, Wesley Everhart, Joseph Newkirk

Materials Science and Engineering Faculty Research & Creative Works

The mechanical properties, specifically ductility, of high performing soft magnets such as Fe-Co alloys are a limiting factor to their broader use in a number of systems. The understanding of the mechanical robustness in these materials is currently insufficient to be able to support the growing interest in applications such as magnetic shielding or electric motors. Fe-Co alloys provide the highest commercially available magnetic saturation and high magnetic permeability but have very poor ductility. The addition of vanadium to these alloys has allowed for significant commercialization and some ductility improvements, but the fundamental reasons for the observed improvements are not …

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Synthesis And Properties Of (Hf,Mo,Ti,W,Zr)B2–(Hf,Mo,Ti,W,Zr)C Dual Phase Ceramics, S. Filipović, S. M. Smith, G. Hilmas, W. Fahrenholtz, N. Obradović, S. Curtarolo Nov 2024

Synthesis And Properties Of (Hf,Mo,Ti,W,Zr)B2–(Hf,Mo,Ti,W,Zr)C Dual Phase Ceramics, S. Filipović, S. M. Smith, G. Hilmas, W. Fahrenholtz, N. Obradović, S. Curtarolo

Materials Science and Engineering Faculty Research & Creative Works

Dense, dual phase (Hf,Mo,Ti,W,Zr)B2–(Hf,Mo,Ti,W,Zr)C ceramics were synthesized with varying contents of Mo and W. The final (Hf0.317Mo0.025Ti0.317W0.025Zr0.317)C–(Hf0.317Mo0.025Ti0.317W0.025Zr0.317)B2 was a nominally pure, dual phase ceramic, while compositions with higher amounts of Mo and W contained multiple phases. The final microstructures had submicron grains due to pinning effects. Vickers hardness values were up to 48.6 ± 2.2 GPa for an applied load of 0.49 N for the ceramic with optimized composition and densification. The solubility limits for Mo and …

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Atmosphere Effects In Laser Powder Bed Fusion: A Review, Ben Brown, Cody Lough, Davis Wilson, Joseph Newkirk, Frank Liou Nov 2024

Atmosphere Effects In Laser Powder Bed Fusion: A Review, Ben Brown, Cody Lough, Davis Wilson, Joseph Newkirk, Frank Liou

Materials Science and Engineering Faculty Research & Creative Works

The use of components fabricated by laser powder bed fusion (LPBF) requires the development of processing parameters that can produce high-quality material. Manipulating the most commonly identified critical build parameters (e.g., laser power, laser scan speed, and layer thickness) on LPBF equipment can generate acceptable parts for established materials and moderately intricate part geometries. The need to fabricate increasingly complex parts from unique materials drives the limited research into LPBF process control using underutilized parameters, such as atmosphere composition and pressure. As presented in this review, manipulating atmosphere composition and pressure in laser beam welding has been shown to expand …

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