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Articles 31 - 60 of 637
Full-Text Articles in Ceramic Materials
Mitigating Hysteresis In Metal-Coated Fibers Via Optimized Thermal Treatment For Advanced Distributed High-Temperature Sensing Applications, Koustav Dey, Rony Kumer Saha, Bohong Zhang, S. Narasimman, Farhan Mumtaz, Jeffrey D. Smith, Rex E. Gerald, Ronald J. O'Malley, Jie Huang
Mitigating Hysteresis In Metal-Coated Fibers Via Optimized Thermal Treatment For Advanced Distributed High-Temperature Sensing Applications, Koustav Dey, Rony Kumer Saha, Bohong Zhang, S. Narasimman, Farhan Mumtaz, Jeffrey D. Smith, Rex E. Gerald, Ronald J. O'Malley, Jie Huang
Electrical and Computer Engineering Faculty Research & Creative Works
Metal-coated optical fibers are widely employed in sensing applications owing to their superior mechanical strength and corrosion resistance. However, their calibration at elevated temperatures is hindered by hysteresis, manifested as discrepancies between heating and cooling cycles, primarily caused by residual strain from mismatched thermal expansion coefficients (TECs) between the metal coating and silica cladding. This research introduces an optimal heat treatment procedure aimed at minimizing the impact of the mismatch in TECs between the cladding and the coating materials that causes the residual strain in gold (Au) and copper (Cu) coated fibers for achieving reliable distributed high temperature sensing up …
Zirconium Carbide Based Materials For Extreme Aerospace Environments, Nathaniel Hyman Blatt
Zirconium Carbide Based Materials For Extreme Aerospace Environments, Nathaniel Hyman Blatt
Doctoral Dissertations
This research focuses on the processing and properties of zirconium carbide-based materials to promote their use in extreme environment aerospace applications, including nuclear thermal propulsion and hyper sonics. Several carbide systems including ZrC, ZrC-Mo cermets, (Zr, Nb)C, and a high entropy carbide were developed. The ZrC-Mo cermet was studied extensively to understand the effect of starting carbide grain size on the final microstructure, composition, elastic moduli, hardness, fracture toughness, room and elevated temperature flexural strength, thermal diffusivity, electrical resistivity, thermal expansion coefficient, and thermal conductivity. It was shown that heat transport in the cermets was dominated by the ZrC phase …
Strontium Titanate For Capacitor And Energy Storage Applications At Cryogenic Temperatures, Hung Trinh
Strontium Titanate For Capacitor And Energy Storage Applications At Cryogenic Temperatures, Hung Trinh
Doctoral Dissertations
This study investigates the dielectric properties of single crystal and ceramic strontium titanate (SrTiO3) for cryogenic capacitor applications from room temperature to 4 K. Permittivity (k) and loss tangent are dependent on temperature, frequency, mechanical stress, and applied DC electric field. Accordingly, the dielectric constant and loss tangent were measured at various frequencies and DC bias levels. Loss tangent data are also presented as equivalent series resistance (ESR). For single crystal SrTiO3, an impurity level of ≈500 ppm barium resulted in an increase of the maximum permittivity to approximately 50,000 at 6 K. This relatively high …
Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar
Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar
Materials Science and Engineering Faculty Research & Creative Works
High-volume industrial continuous hot-rolled steel heat treatment processes involve sophisticated multi-phase modeling. The performance of a given process can be optimized by coupling phase transformation kinetics with the cooling conditions of the process. This study develops a multiphysics model to simulate an intensive quenching process for steel, which is inherently transient and highly dependent on numerous parameters. The simulated object was a Jominy end-quenched specimen geometry using two commercial steels, AISI 4130 and AISI 4140, with the goal of transferring a verified methodology to the heat treatment process for industrial heavy-section products (bars, slabs). The simulation employs thermal, mechanical, and …
Thermal Properties Of High Entropy Dual Phase (Hf,Nb,Ta,Ti,Zr,)C-(Hf,Nb,Ta,Ti,Zr)B2 Ceramics: Comparison With The High Entropy Single-Phase Ceramics And The Effect Of Wc Additions, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas
Thermal Properties Of High Entropy Dual Phase (Hf,Nb,Ta,Ti,Zr,)C-(Hf,Nb,Ta,Ti,Zr)B2 Ceramics: Comparison With The High Entropy Single-Phase Ceramics And The Effect Of Wc Additions, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas
Materials Science and Engineering Faculty Research & Creative Works
The heat capacity, thermal diffusivity and thermal conductivity of (Hf,Nb,Ta,Ti,Zr)C-(Hf,Nb,Ta,Ti,Zr)B2 high entropy dual phase ceramics were evaluated from room temperature to 1800 °C and compared with the constituent high entropy single phase ceramics of the same nominal compositions. Thermal conductivity of the (Hf,Nb,Ta,Ti,Zr)C-(Hf,Nb,Ta,Ti,Zr)B2 dual phase ceramic increased from 17.7 W m−1 K−1 at room temperature to 54 W m−1 K−1 at 1800 °C. The addition of WC to the dual phase ceramic reduced its thermal conductivity. For the addition of 5 wt% WC, room temperature thermal conductivity was 16.8 W m−1 K−1 …
Effects Of Wc Additions On The Phase Formation Of (Hf,Nb,Ta,Ti,Zr)C-(Hf,Nb,Ta,Ti,Zr)B2 High Entropy Dual Phase Ceramics, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas
Effects Of Wc Additions On The Phase Formation Of (Hf,Nb,Ta,Ti,Zr)C-(Hf,Nb,Ta,Ti,Zr)B2 High Entropy Dual Phase Ceramics, Rubia Hassan, William G. Fahrenholtz, Gregory E. Hilmas
Materials Science and Engineering Faculty Research & Creative Works
High entropy dual phase (Hf,Nb,Ta,Ti,Zr)C-(Hf,Nb,Ta,Ti,Zr)B2 ultra-high temperature ceramics were produced from powders synthesized by boro-carbothermal reduction. Systematic additions of 2.5 wt%, 5 wt%, and 10 wt% WC were incorporated after powder synthesis. Additions of 2.5 wt% and 5 wt% WC dissolved into the host ceramics, resulting in complete solid solution formation and nearly full densification. In contrast, a secondary monoboride phase evolved for the composition with 10 wt% WC, in addition to the main high entropy carbide and diboride phases. Thermodynamic analysis revealed that WB formation was favorable for WC additions in the presence of metal diborides at the sintering …
Micro/Nanomechanical Properties Of Top-Seeded Melt Grown Ybco Single Crystals Determined Using Depth Sensing Indentation, Ugur Kolemen, Cafer Mert Yesilkanat, Fikret Yilmaz, Fatih Dogan, Orhan Uzun
Micro/Nanomechanical Properties Of Top-Seeded Melt Grown Ybco Single Crystals Determined Using Depth Sensing Indentation, Ugur Kolemen, Cafer Mert Yesilkanat, Fikret Yilmaz, Fatih Dogan, Orhan Uzun
Materials Science and Engineering Faculty Research & Creative Works
Mechanical properties of the bulk YBa2Cu3O7-x (YBCO) single crystal superconductor, prepared by using the Top Seeded Melt Growth (TSMG) method, were determined. Property measurements were conducted by the nanoindentation method under various loads and the micro indentation method at different temperatures. Hardness (H) and reduced elastic modulus (Er) values were calculated by using the Oliver–Pharr method. According to hf/h max values found from load- displacement curves, there is a sink in behavior around outer rim of the indents that was confirmed by atomic force microscopy (AFM) analysis. Nanoindentation analyses conducted on upper section, middle section and subsection revealed that all …
Variable-Temperature Plasmonic High-Entropy Carbides, Simon Divilov, Sean D. Griesemer, Robert C. Koennecker, Michael J. Ammendola, Adam C. Zettel, Hagen Eckert, Jeffrey R. Shallenberger, Xiomara Campilongo, William G. Fahrenholtz, Arrigo Calzolari, Douglas E. Wolfe, Stefano Curtarolo
Variable-Temperature Plasmonic High-Entropy Carbides, Simon Divilov, Sean D. Griesemer, Robert C. Koennecker, Michael J. Ammendola, Adam C. Zettel, Hagen Eckert, Jeffrey R. Shallenberger, Xiomara Campilongo, William G. Fahrenholtz, Arrigo Calzolari, Douglas E. Wolfe, Stefano Curtarolo
Materials Science and Engineering Faculty Research & Creative Works
Effective thermal management at variable and extreme temperatures face limitations for the development of novel energy and aerospace applications. Plasmonic approaches, shown to be capable of tailoring black-body emission, could be effective if materials with high-temperature and tunable plasmonic resonance were available. Here, we report a synergy between experimental and theoretical results proving that many high-entropy transition metal carbides, consisting of four or more metals at equal molar ratio, have plasmonic resonance at room, high (>1000∘C) and variable temperatures. We also found that these high-entropy carbides can be tuned and show considerable plasmonic thermal cycling stability. This paradigm-shift approach …
Data Driven Design Of Ultra High Performance Concrete Prospects And Application, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Jie Huang, Ashutosh Goel, Aditya Kumar, Narayanan Neithalath
Data Driven Design Of Ultra High Performance Concrete Prospects And Application, Bryan K. Aylas-Paredes, Taihao Han, Advaith Neithalath, Jie Huang, Ashutosh Goel, Aditya Kumar, Narayanan Neithalath
Electrical and Computer Engineering Faculty Research & Creative Works
Ultra-high-performance concrete (UHPC) is a specialized class of cementitious composites that is increasingly used in various applications, including bridge decks, connections between precast components, piers, columns, overlays, and the repair and strengthening of bridge elements. The mechanical and durability properties of UHPC are significantly influenced by factors such as low water-to-binder ratios, the inclusion of supplementary cementitious materials (SCMs), and fiber reinforcement. Machine learning (ML) has been employed to predict the performance of UHPC and optimize its mixture designs by using various raw materials. This study first provides a comprehensive review of ML applications in UHPC, focusing on predicting workability, …
Elucidating The Effects Of Water Activity On The Hydration Kinetics And Thermodynamics Of Ye’Elimite–Calcium Sulfate Hydrate Systems, Godwin I. Ogbuehi, Rupack R. Halder, Aditya Kumar, Gaurav Sant, Monday U. Okoronkwo
Elucidating The Effects Of Water Activity On The Hydration Kinetics And Thermodynamics Of Ye’Elimite–Calcium Sulfate Hydrate Systems, Godwin I. Ogbuehi, Rupack R. Halder, Aditya Kumar, Gaurav Sant, Monday U. Okoronkwo
Materials Science and Engineering Faculty Research & Creative Works
Relative humidity and water activity (aH) reductions have been known to suppress the hydration of anhydrous cement clinker phases. However, the relationship between ye'elimite (C4A3$) hydration kinetics and water activity remain unclear. This study employs experimental and thermodynamic modeling approaches to investigate the influence of water activity on ye'elimite hydration in the "C4A3$ + water", and "C4A3$ + gypsum + water" systems. Experimental findings indicate that as water activity decreases, C4A3$ hydration diminishes until the reaction is brought to a halt at a threshold aH. The critical aHand corresponding solubility constant of C4A3$ (KC4A3S¯) estimated from thermodynamic analysis are 0.46 …
Effects Of Yttrium And Barium Trace Impurities On The Dielectric Properties Of Srtio3 (111) Single Crystals At Cryogenic Temperatures, Hung Trinh, Alan Devoe, Fatih Dogan
Effects Of Yttrium And Barium Trace Impurities On The Dielectric Properties Of Srtio3 (111) Single Crystals At Cryogenic Temperatures, Hung Trinh, Alan Devoe, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Commercially available single crystals of (111) SrTiO3 were found to contain impurities of varying amounts that strongly affected their dielectric performance at cryogenic temperatures. Three crystals with total impurities of 111, 126, and 625 ppm, primarily of barium and yttrium, were analyzed. Relative permittivity (εr) and loss tangent were investigated with high resolution as a function of temperature (4 K to 100 K), DC voltage (0 V/cm to 800 V/cm), and frequency (100 Hz to 1 MHz). An impurity level as low as ≈500 ppm barium resulted in an increase of the maximum permittivity (εm) to approximately 50,000 at …
Extraction Of Aluminum From Lunar Regolith Through Molten Salt Electrolysis, Jacob N. Ortega, Todd P. Sander, Jeffrey D. Smith, Fateme Rezaei, David J. Bayless, William Schonberg, Daniel S. Stutts, Frank D. Han
Extraction Of Aluminum From Lunar Regolith Through Molten Salt Electrolysis, Jacob N. Ortega, Todd P. Sander, Jeffrey D. Smith, Fateme Rezaei, David J. Bayless, William Schonberg, Daniel S. Stutts, Frank D. Han
Materials Science and Engineering Faculty Research & Creative Works
This paper presents the methodology, development, and results of an end-to-end regolith-to-metal concept for producing aluminum in-situ on the lunar surface, namely, the Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE) method. Using electrolytic reduction, aluminum oxide (i.e., alumina) can be reduced into aluminum and oxygen via electrolysis in a molten salt bath. A steady supply of hydrogen chloride could allow this in-situ resource utilization (ISRU) method to supply several necessary materials consumed in the electrolytic reduction step of the process to produce bulk aluminum metal, oxygen, water, and silica from anorthite abundant in lunar highland regions. In this …
Microstructure Densification In Cement Pastes Enabled By Novel Graphene Types, Sahil Surehali, Taihao Han, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath
Microstructure Densification In Cement Pastes Enabled By Novel Graphene Types, Sahil Surehali, Taihao Han, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath
Materials Science and Engineering Faculty Research & Creative Works
The primary barriers hindering graphene's widespread adoption as a performance-enhancing additive in cement-based systems have traditionally been its prohibitive cost and the sustainability concerns associated with conventional manufacturing processes. However, these impediments have recently been mitigated by advancements in detonation synthesis techniques, enabling scalable, cost-effective, and environmentally favorable production of novel graphene types—specifically fractal graphene (FG) and reactive graphene (RG). This paper explores the influence of ultra-low dosages of FG and RG (≤ 0.04 % by mass of cement, which results in ∼20 % increase in compressive strengths) on the pore-structure features of cement pastes. Compared to the control paste, …
In Situ High-Temperature Raman Spectroscopy For Online Eaf Slag Analysis, Bohong Zhang, Hanok Tekle, Ronald J. O'Malley, Jeffrey D. Smith, Farhan Mumtaz, Jie Huang
In Situ High-Temperature Raman Spectroscopy For Online Eaf Slag Analysis, Bohong Zhang, Hanok Tekle, Ronald J. O'Malley, Jeffrey D. Smith, Farhan Mumtaz, Jie Huang
Electrical and Computer Engineering Faculty Research & Creative Works
Real-time monitoring of slag chemistry is critical for optimizing Electric Arc Furnace (EAF) steelmaking operations, where dynamic variations in slag composition directly influence slag foaming, refractory degradation, and thermal efficiency. Conventional techniques such as X-ray fluorescence (XRF), Fourier-transform infrared (FTIR), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) are commonly used to analyze slag composition, but their offline nature and equipment constraints limit their applicability for online monitoring in harsh industrial environments. To address this challenge, we present an in situ, high-temperature analytical approach that integrates Raman spectroscopy with a custom-designed fiber-optic probe for real-time slag characterization at …
Enabling Carbon Dioxide Mineralization And Active Set Control In Portlandite-Based Cementitious Suspensions, Xiaodi Dai, Sharu Bhagavathi Kandy, Rui Xiao, Manas Sarkar, Shubham Wani, Thiyagarajan Ranganathan, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gädt, Samanvaya Srivastava, Gaurav Sant
Enabling Carbon Dioxide Mineralization And Active Set Control In Portlandite-Based Cementitious Suspensions, Xiaodi Dai, Sharu Bhagavathi Kandy, Rui Xiao, Manas Sarkar, Shubham Wani, Thiyagarajan Ranganathan, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gädt, Samanvaya Srivastava, Gaurav Sant
Materials Science and Engineering Faculty Research & Creative Works
The real-time control of concrete's stiffening allows users to better control pumping and extrusion during 3D-printing processes. Here, a portlandite-based cementitious formulation (i.e., slurry or suspension) that features the potential for rapid CO2 uptake is adapted for 3D-printing applications. In particular, we showcase a portlandite-fly ash binder system combined with a thermo responsive polymer, wherein precise control via thermal activation allows set control and rapid solidification. Through the thermally induced polymerization of polyacrylamide, the hybrid binder system rapidly undergoes stiffening at trigger onset temperatures ranging from 60 °C to 80 °C, exhibiting average stiffening rates of up to 2600 …
Ultra-Low Dosages Of Novel Graphene Types Enhance The Rheological Properties And Buildability Of 3d Printed Binders, Sahil Surehali, Akshay Venkatachalam, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath
Ultra-Low Dosages Of Novel Graphene Types Enhance The Rheological Properties And Buildability Of 3d Printed Binders, Sahil Surehali, Akshay Venkatachalam, Ranjith Divigalpitiya, Aditya Kumar, Narayanan Neithalath
Materials Science and Engineering Faculty Research & Creative Works
The use of graphene as a high-performance concrete additive is attractive; but, its cost and concerns about production scalability and dispersion efficiency in concrete are impediments to widespread use. This study explores the impact of ultra-low dosages (≤0.02 % by mass of binder) of two novel graphene types—fractal graphene (FG) and reactive graphene (RG)—produced through a cost-effective, environmentally friendly, and scalable process, on the rheological properties of 3D-printable concrete. Both FG and RG significantly enhance the dynamic and static yield stresses and viscoelastic properties of the binder, with RG-modified mixtures exhibiting slightly more pronounced enhancements due to the presence of …
Thermomechanical And Thermal Characterization Of Pressureless Sintered Tib2, Simone Taraborelli, Simone Failla, Diletta Sciti, Steven M. Smith, Jeremy Watts, William G. Fahrenholtz, Greg E. Hilmas
Thermomechanical And Thermal Characterization Of Pressureless Sintered Tib2, Simone Taraborelli, Simone Failla, Diletta Sciti, Steven M. Smith, Jeremy Watts, William G. Fahrenholtz, Greg E. Hilmas
Materials Science and Engineering Faculty Research & Creative Works
The impact of high-energy milling using WC[sbnd]Co media on the pressureless sintering and properties of TiB2 was studied. After 30 mins of milling, samples sintered at 2200 °C achieved a high relative density (>98 %) and a fine mean grain size (<2 >µm). In the microstructure WxBy phases, often containing Co, were observed at triple points, due to contamination from the milling media. Moreover, core-rim structures with multiple rims were detected: the cores consisted of pure TiB2 grains, the rims were (TixWy)B2 solid solutions. The core-rim formation was significantly more pronounced compared to a reference sample of …
Reliability Of Cazro3 And Mgo Capacitors At High Temperatures, Alan Devoe, Hung Trinh, Fatih Dogan
Reliability Of Cazro3 And Mgo Capacitors At High Temperatures, Alan Devoe, Hung Trinh, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Calcium zirconate and magnesium oxide have both been found to have useful dielectric properties at high temperatures. Multilayer ceramic capacitors (MLCCs) were made with these dielectrics and platinum electrodes. The relationship between the lifespan (mean-time to failure) and applied voltage was determined using Weibull statistics. CaZrO3 capacitors were tested between 550◦C and600◦C while MgO capacitors were tested between 600◦C and 650◦C. The temperature coefficient Ea and the voltage coefficient n of the Prokopowicz Vaskas equation were determined under various test conditions. Activation energiesforcalciumzirconateandmagnesiumoxidewere3.25eVand3.48eV, respectively. Resistance degradation of CaZrO3 and MgO capacitors, tested at 600◦Cand250V, were compared.
Intermediate Stage Densification Kinetics Of High-Entropy Ceramics During Spark Plasma Sintering, Steven M. Smith, William G. Fahrenholtz, Greg E. Hilmas, Stefano Curtarolo
Intermediate Stage Densification Kinetics Of High-Entropy Ceramics During Spark Plasma Sintering, Steven M. Smith, William G. Fahrenholtz, Greg E. Hilmas, Stefano Curtarolo
Materials Science and Engineering Faculty Research & Creative Works
The intermediate stage densification kinetics of (Hf, Nb, Ta, Ti, Zr) B2 and (Hf, Nb, Ta, Ti, Zr) C were studied using a Coble creep rate model. (Hf, Nb, Ta, Ti, Zr) B2 was synthesized by boro/carbothermal reduction and (Hf, Nb, Ta, Ti, Zr) C was synthesized by carbothermal reduction. Both ceramics were densified by spark plasma sintering at 1700–1850°C. The activation energies for densification were 575 ± 53 kJ/mol for the high-entropy boride and 646 ± 4 kJ/mol for the high-entropy carbide. The densification mechanisms were grain boundary diffusion for the high-entropy boride and lattice diffusion for the high-entropy …
Effects Of Processing And Microstructure On The Oxidation Of Zrb2-Sic In Co2, Marharyta Lakusta, Jeremy L. Watts, William G. Fahrenholtz, David W. Lipke
Effects Of Processing And Microstructure On The Oxidation Of Zrb2-Sic In Co2, Marharyta Lakusta, Jeremy L. Watts, William G. Fahrenholtz, David W. Lipke
Materials Science and Engineering Faculty Research & Creative Works
Oxidation kinetics and oxide scale microstructures were compared for ZrB2-30 vol% SiC composites fabricated by hot press sintering of powders and by pressure less sintering of additively manufactured billets. Oxidation in CO2 was conducted at temperatures up to 1400 °C with durations up to 900 h. All specimens exhibited parabolic oxidation kinetics. Materials with similar composition but different processing histories exhibited differences in oxidation behavior that become evident at extended durations (200–900 h) and higher temperatures (1200–1400 °C). Oxidation rates generally increased with grain size, e.g., at 1000 °C for 200 h, oxide scale thickness increased from 36 to …
Interfacial Defect Properties Of High-Entropy Carbides: Stacking Faults, Shockley Partial Dislocations, And A New Evans-Polanyi-Semenov Relation, Samuel E. Daigle, Stefano Curtarolo, William G. Fahrenholtz, Jon Paul Maria, Douglas E. Wolfe, Eva Zurek, Donald W. Brenner
Interfacial Defect Properties Of High-Entropy Carbides: Stacking Faults, Shockley Partial Dislocations, And A New Evans-Polanyi-Semenov Relation, Samuel E. Daigle, Stefano Curtarolo, William G. Fahrenholtz, Jon Paul Maria, Douglas E. Wolfe, Eva Zurek, Donald W. Brenner
Materials Science and Engineering Faculty Research & Creative Works
Using first principles calculations, {111} intrinsic stacking fault (ISF) energies in groups IVB, VB, and VIB high-entropy transition metal carbides (HETMCs) are shown to be predictable from an optimized rule of mixtures based on the atomic arrangement near the stacking fault. A composition-independent linear relationship is demonstrated between the ISF energies and the unstable stacking fault (USF) energies along the (112¯){111} γsurface slip path. This relationship represents a new application of the Evans-Polanyi-Semenov principle by treating the ISF and USF energies as analogous to the heat of reaction and transition state barrier in chemical reactions. Further, a full defect energy …
Numerical Simulation Of Heat Transfer In Self-Propagating High-Temperature Synthesis (Shs)-Based Calcination Of Limestone, Sayee Srikarah Volaity, Shubham Agrawal, Srinivas Kilambi, Patrick Phelan, Aditya Kumar, Narayanan Neithalath
Numerical Simulation Of Heat Transfer In Self-Propagating High-Temperature Synthesis (Shs)-Based Calcination Of Limestone, Sayee Srikarah Volaity, Shubham Agrawal, Srinivas Kilambi, Patrick Phelan, Aditya Kumar, Narayanan Neithalath
Materials Science and Engineering Faculty Research & Creative Works
Calcination of limestone, a high temperature (∼900 °C) process that emits 44 % of the mass of limestone as CO2, is a critical process in the production of many industrially important materials. To soften the CO2-related impacts of traditional calcination, and to enable ultrafast synthesis of lime, a novel approach based on self-propagating high-temperature synthesis (SHS) has been put forward. SHS uses exothermic heat released by the combustion of fuel intermixed with the reactants to advance the reaction, and hence requires the provision of lower external temperatures. This study introduces a microstructure-guided modeling approach to understand …
Compositionally Complex Diborides: Competing Solubility During Sintering And Properties, Laura Silvestroni, Carlo Baldisserri, Jacopo Matteo Tabaglio, Nicola Gilli, Jeremy Watts, Steven M.I. Smith, Gregory E. Hilmas, William G. Fahrenholtz
Compositionally Complex Diborides: Competing Solubility During Sintering And Properties, Laura Silvestroni, Carlo Baldisserri, Jacopo Matteo Tabaglio, Nicola Gilli, Jeremy Watts, Steven M.I. Smith, Gregory E. Hilmas, William G. Fahrenholtz
Materials Science and Engineering Faculty Research & Creative Works
An ultra-high temperature ceramic based on ZrB2, TiB2, and SiC was hot pressed to full density at 1850 °C. Addition of 5 vol% of different metal-compounds, in the form of HfC, VC, NbC or CrB2, increased the densification temperature to 1910 °C. The resulting compositionally complex ceramics had homogeneous microstructures with boride grains exhibiting core-shell features. The shell was a solid solution containing variable amounts of the three metals. Notably, TiB2 remained as a discrete phase in the reference material and in the presence of the V- and Cr- based additions, whilst it dissolved into the main ZrB2-based grains for …
Fabrication Of Ultra High-Temperature Compact Heat Exchanger By Extrusion-Based Ceramic Additive Manufacturing, Abid Hasan Rafi, David W. Lipke, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu
Fabrication Of Ultra High-Temperature Compact Heat Exchanger By Extrusion-Based Ceramic Additive Manufacturing, Abid Hasan Rafi, David W. Lipke, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu
Miners Solving for Tomorrow Research Conference
No abstract provided.
Sustainable Solutions To Eutrophication: The Role Of Glass Fertilizers, Lucas Greiner, Charmayne Lonergan
Sustainable Solutions To Eutrophication: The Role Of Glass Fertilizers, Lucas Greiner, Charmayne Lonergan
Miners Solving for Tomorrow Research Conference
No abstract provided.
Microstructural Evolution Of High-Entropy Carbide Ceramics, Elizabeth Pritchett, William Fahrenholtz, Greg Hilmas, Steven Smith
Microstructural Evolution Of High-Entropy Carbide Ceramics, Elizabeth Pritchett, William Fahrenholtz, Greg Hilmas, Steven Smith
Miners Solving for Tomorrow Research Conference
No abstract provided.
Synergy In Materials: Leveraging Phosphosilicate Waste Forms For Electrochemical Salt Waste, Jonathan S. Evarts, Brian J. Riley, Charmayne E. Lonergan, Michaella S. Harris, Jincheng Bai, Eric W. Bohannan, Iheanyichukwu Ajoku, Saehwa Chong, John S. Mccloy
Synergy In Materials: Leveraging Phosphosilicate Waste Forms For Electrochemical Salt Waste, Jonathan S. Evarts, Brian J. Riley, Charmayne E. Lonergan, Michaella S. Harris, Jincheng Bai, Eric W. Bohannan, Iheanyichukwu Ajoku, Saehwa Chong, John S. Mccloy
Materials Science and Engineering Faculty Research & Creative Works
Waste forms containing glassy and crystalline phosphate and silicate phases were produced to immobilize salt waste simulants from pyro processing and characterized by using Raman spectroscopy, Mössbauer spectroscopy, X-ray diffraction, scanning electron microscopy, heat capacity, and chemical durability measurements. In this work, a phosphosilicate waste form is presented to leverage the benefits of both borosilicate glasses and iron phosphate glasses. To improve waste loading, prior to immobilization, salt simulants were successfully dechlorinated using ammonium dihydrogen phosphate, mixed with a borosilicate frit (5–30 wt. %) and Fe2O3, and vitrified. Additions of 2.5–15 wt. % borosilicate glass (NBS3) improved normalized release rates …
A Low-Carbon Approach For Lime Production Using Self-Propagating High Temperature Synthesis-Driven Limestone Calcination, Shubham Agrawal, Sayee Srikarah Volaity, Srinivas Kilambi, Aditya Kumar, Narayanan Neithalath
A Low-Carbon Approach For Lime Production Using Self-Propagating High Temperature Synthesis-Driven Limestone Calcination, Shubham Agrawal, Sayee Srikarah Volaity, Srinivas Kilambi, Aditya Kumar, Narayanan Neithalath
Materials Science and Engineering Faculty Research & Creative Works
Limestone calcination produces calcium oxide (or lime), that forms the basis for the manufacturing of many critical engineering materials such as cement and iron-and-steel. Limestone calcination—an endothermic reaction—is regarded as one of the most energy-and-CO2 intensive industrial chemical reactions, and is facilitated by fossil fuels, since the high temperature requirement (∼900 °C) renders it less conducive to electrification through renewable energy sources. In this study, a novel, low-temperature (∼450 °C) pathway for ultrafast calcination of limestone using combustion synthesis or self-propagating high-temperature synthesis (SHS) is developed. SHS leverages exothermic heat from the combustion of lignin or biomass—as low-carbon fuels—mixed …
Design And Function Of Thermoresponsive-Ultrafast Stiffening Suspension Formulations For 3d Printing, Sharu Bhagavathi Kandy, Sebastian Remke, Thiyagarajan Ranganathan, Shubham Kiran Wani, Xiaodi Dai, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gädt, Samanvaya Srivastava, Gaurav Sant
Design And Function Of Thermoresponsive-Ultrafast Stiffening Suspension Formulations For 3d Printing, Sharu Bhagavathi Kandy, Sebastian Remke, Thiyagarajan Ranganathan, Shubham Kiran Wani, Xiaodi Dai, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Torben Gädt, Samanvaya Srivastava, Gaurav Sant
Materials Science and Engineering Faculty Research & Creative Works
An inability to accurately control the rate and extent of solidification of cementitious suspensions is a major impediment to creating geometrically complex structural shapes via 3D printing. In this work, we have developed a thermoresponsive rapid stiffening system that will stiffen suspensions of minerals such as quartz, limestone, portlandite, and Ordinary Portland Cement (OPC) over a wide pH range. When exposed to trigger temperatures between 40 °C and 70 °C, the polymer binder system undergoes a thermally triggered free radical polymerization (FRP) reaction, leading to an ultrafast stiffening of the suspension at an average rate on the order of 1 …
Compositionally Complex Alb2-Type Diborides In Dissociated Air Plasma, F. Monteverde, C. Pellegrini, M. Balat-Pichelin, William Fahrenholtz, Greg Hilmas
Compositionally Complex Alb2-Type Diborides In Dissociated Air Plasma, F. Monteverde, C. Pellegrini, M. Balat-Pichelin, William Fahrenholtz, Greg Hilmas
Materials Science and Engineering Faculty Research & Creative Works
Multi-metal compositionally complex (CC) AlB2-type diboride solid solutions (SS) containing IV-V-VI group elements are garnering a steadily growing research interest. The present work explores the composition dependence of oxidation resistance on nominally equiatomic (Hf,Me,Ta,Ti,Zr)B2 SS, Me = Nb or Cr, exposed to a dissociated air plasma (total pressure of about 1 kPa): specimens were exposed for 5 min at some selected set points between 1800 K and 2500 K using a solar furnace. The CC diboride with Nb showed superior resistance to oxidation compared to that with Cr. The experimental results showed good agreement with predictions based on a thermodynamic …