Open Access. Powered by Scholars. Published by Universities.®

Materials Science and Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

2023

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 901 - 930 of 985

Full-Text Articles in Materials Science and Engineering

Study Of Corrosion Properties Of Carbon Steel, 304 And 316l Stainless Steels In Sulfuric Acid And Their Degradation Products, Eakapoj Khamme, Rachsak Sakdanuphab Jan 2023

Study Of Corrosion Properties Of Carbon Steel, 304 And 316l Stainless Steels In Sulfuric Acid And Their Degradation Products, Eakapoj Khamme, Rachsak Sakdanuphab

Journal of Metals, Materials and Minerals

In this study, corrosion properties of carbon steel and stainless steels, and degradation of sulfuric acid by the corrosion mechanism are presented. Carbon steel (CS), 304 stainless steel (SS304), and 316L stainless steel (SS316L) specimens were analyzed through their electrochemical response by using a potentiostat measurement. The specimens were submerged in concentrated 98 wt.% of H2SO4 acid for 0 day to 60 day. The degradation of H2SO4 was determined by its volume change, turbidity, and color due to the corrosion mechanism. Corrosion rate of CS, SS304 and SS316L specimens are 43.237 mm/year, 0.420 mm/year and 0.086 mm/year, respectively. After 60 …

Go to article

Microstructure And Mechanical Properties Of 0.2c-3.9al-1.12mn-0.3mo Δ-Trip Steel As A Function Of Isothermal Bainitic Transformation Temperature, Mahsa Gholambargani, Yahya Palizdar, Ali Khanlakhani, Ali Khanlakhani Jan 2023

Microstructure And Mechanical Properties Of 0.2c-3.9al-1.12mn-0.3mo Δ-Trip Steel As A Function Of Isothermal Bainitic Transformation Temperature, Mahsa Gholambargani, Yahya Palizdar, Ali Khanlakhani, Ali Khanlakhani

Journal of Metals, Materials and Minerals

The present investigation employed a two-stage heat treatment on a δ-transformation-induced plasticity (TRIP) steel comprising 0.2C–4Al–1.2Mn–0.3Mo (wt%). The mechanical and microstructural characteristics that result from varied isothermal bainitic transformation (IBT) temperatures following inter-critical annealing at 820℃ for 10 min are thoroughly analyzed. The microstructure of the steels consisted of δ-ferrite, α-ferrite, bainitic ferrite, retained austenite (RA), and martensite, resulting in an optimum combination of the ultimate tensile strength (UTS) and total elongation (TE). The results of the investigation showed that IBT temperature had an effect on the stability of RA and the martensitic transition. Due to the increased mechanical stability …

Go to article

Improvement Of Specific Capacity Of Lithium Iron Phosphate Battery By Increasing The Surface Area And Electrical Conductivity Of Cathode Electrode Using Graphene Foam, Phurida Kokmat, Patiphat Matsayamat, Kunaree Wongrach, Piyaporn Surinlert, Akkawat Ruammaitree Jan 2023

Improvement Of Specific Capacity Of Lithium Iron Phosphate Battery By Increasing The Surface Area And Electrical Conductivity Of Cathode Electrode Using Graphene Foam, Phurida Kokmat, Patiphat Matsayamat, Kunaree Wongrach, Piyaporn Surinlert, Akkawat Ruammaitree

Journal of Metals, Materials and Minerals

Lithium iron phosphate (LFP) is widely used as an active material in a cathode electrode for lithium-ion batteries (LIBs). LFP has many remarkable properties such as high working voltage and excellent thermal stability. However, it suffers with slow ion diffusion and low electrical conductivity. Graphene foam has many outstanding properties such as large surface area and great electrical conductivity. These properties are suitable for improving the cathode electrode. In this work, the graphene foam was synthesized by chemical vapor deposition. The cathode electrode was prepared by dropping the LFP on the graphene foam. We found that the specific capacity of …

Go to article

Synthesis Of Carbon Nanowalls By Oxy-Acetylene Torch Method, Bauyrzhan Zhumadilov, Aidar Kenzhegulov, Renata Nemkayeva, Gulmira Partizan, Yerassyl Yerlanuly, Maratbek Gadbullin Jan 2023

Synthesis Of Carbon Nanowalls By Oxy-Acetylene Torch Method, Bauyrzhan Zhumadilov, Aidar Kenzhegulov, Renata Nemkayeva, Gulmira Partizan, Yerassyl Yerlanuly, Maratbek Gadbullin

Journal of Metals, Materials and Minerals

This work presents a relatively new method for the synthesis of carbon nanowalls (CNWs) based on oxy-acetylene torch as a function of deposition time. The morphological and structural properties of the obtained CNW films were studied by scanning electron microscopy and Raman spectroscopy. Changes in the morphology and structural properties of the CNW films depending on the synthesis time were revealed. Shorter growth times lead to the formation of thinner CNW films with a dense labyrinth-like structure, while longer growth times lead to thicker CNW films with a petal-like structure. In addition, this study opens up the possibility of synthesizing …

Go to article

Sustainable Innovation In Ballistic Vest Design: Exploration Of Polyurethane-Coated Hemp Fabrics And Reinforced Sandwich Epoxy Composites Against 9 Mm And .40 S&W Bullets, Tannachart Wantang, Manop Pipathattakul, Fasai Wiwatwongwana Jan 2023

Sustainable Innovation In Ballistic Vest Design: Exploration Of Polyurethane-Coated Hemp Fabrics And Reinforced Sandwich Epoxy Composites Against 9 Mm And .40 S&W Bullets, Tannachart Wantang, Manop Pipathattakul, Fasai Wiwatwongwana

Journal of Metals, Materials and Minerals

This research aimed to evaluate the bulletproof capabilities of hemp fabrics and optimize the design factors for effective ballistic vests. Three main aspects were investigated: enhancing toughness with polyurethane-coated hemp fabrics, determining optimal placement of fabric-reinforced hemp epoxy composites in various configurations, and identifying the optimal number of fabric layers for performance against 9 mm and .40 S&W bullets. Penetration depth was measured in ballistic gelatin to analyze the results. The study showed strong statistical correlations between factor variables and penetration depth shifts. The most effective strategies included polyurethane-coated hemp on all layers and increased layering. The ammunition of 9 …

Go to article

Structural And Electrical Properties Of 0.98(Ko0.5na0.5onboo3)-0.02(Bio0.5nao0.5tioo3) Ceramics, Swayam Aryam Behera, Sugato Hajra, Swati Panda, Ali Amanat, P. G. R. Achary Jan 2023

Structural And Electrical Properties Of 0.98(Ko0.5na0.5onboo3)-0.02(Bio0.5nao0.5tioo3) Ceramics, Swayam Aryam Behera, Sugato Hajra, Swati Panda, Ali Amanat, P. G. R. Achary

Journal of Metals, Materials and Minerals

In the present communication, lead-free ceramics having composition 0.98(K0.5Na0.5NbO3)-0.02(Bi0.5Na0.5TiO3) were synthesized by a high-temperature solid-state reaction route. The Rietveld refinement for the 0.98KNN-0.02BNT reveals an MPB with phase fraction Amm2 (87.76 %) and Pm-3m (12.27%). The SEM study predicted a mean diameter of 0.98KNN-0.02BNT grains as 0.52µm±0.19. The 0.98KNN-0.02BNTceramic displayed a typical hysteresis loop with a remnant polarisation(Pr) of 7.0 μC/cm2, saturation polarization (Ps) of 16 μC/cm2, and a coercive field (Ec) of 26 kV/mm. The electrical, Raman spectra, dielectric, and hysteresis loop study supported a morphotropic phase boundary. The synthesized KNN-BNT lead-free material can be an excellent material for …

Go to article

Higher-Order Effects In Biaxial Flexure Of Gfrp I-Section Beams, Zia Razzaq, Faridoon Z. Razzaq Jan 2023

Higher-Order Effects In Biaxial Flexure Of Gfrp I-Section Beams, Zia Razzaq, Faridoon Z. Razzaq

Civil & Environmental Engineering Faculty Publications

A theoretical study of Glass Fiber Reinforced Polymer (GFRP) beams subjected to biaxial bending moments is presented with a focus on the influence of higher-order effects on maximum normal stresses. It is shown that the biaxial bending type of loading causes a dramatic increase in the maximum normal stress for a GFRP beam when induced torsional effects are included. The study demonstrates that the traditional first-order theory can grossly underestimate the maximum normal stress in a GFRP beam. Based on the numerical results presented using a higher-order theory which also accounts for induced warping normal stresses, the maximum normal stress …

Go to article

Elastoplastic Quasi-Static And Impact Load Response Of Steel Structure Sub-Assemblage With Cfrp Strips, Ali Al Aloosi, Zia Razzaq Jan 2023

Elastoplastic Quasi-Static And Impact Load Response Of Steel Structure Sub-Assemblage With Cfrp Strips, Ali Al Aloosi, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

Presented in this paper is the outcome of an experimental investigation of the elastoplastic quasi-static and impact load response of a steel sub-assemblage constructed using a pair of hollow square section members with or without Carbon Fiber Reinforced Polymer (CFRP) strips. The sub-assemblage consists of a long structural member welded to a short member, thus representing a typical combination of a column and a beam on the face of a multi-story steel building frame. The column is subjected to a lateral quasi-static or impact load. Tests are conducted on four separate steel sub-assemblages. The first two tests are conducted with …

Go to article

Mechanical Properties Of Zrb2 Ceramics Determined By Two Laboratories, Jeffrey J. Swab, Jecee Jarman, William Fahrenholtz, Jeremy Lee Watts Jan 2023

Mechanical Properties Of Zrb2 Ceramics Determined By Two Laboratories, Jeffrey J. Swab, Jecee Jarman, William Fahrenholtz, Jeremy Lee Watts

Materials Science and Engineering Faculty Research & Creative Works

The mechanical properties for zirconium diboride (ZrB2) were measured at two laboratories and compared. Two billets of ZrB2 were prepared by hot-pressing commercial powder. The relative densities of the billets were >99% and with an average grain size of 5.9 ± 4.5 µm. Both laboratories prepared American Society for Testing and Materials (ASTM) C1161 B-bars for strength and ASTM C1421 bars with notch configuration A for fracture toughness. Specimens were machined by diamond grinding at the Army Research Laboratory (ARL) and electrical discharge machining (EDM) at Missouri S&T. Strength bars tested at Missouri S&T were polished to a.25 μm finish …

Go to article

Coating Compositions And Methods For Using The Same, Fateme Rezaei, Thomas P. Schuman, Glenn C. Morrison Jan 2023

Coating Compositions And Methods For Using The Same, Fateme Rezaei, Thomas P. Schuman, Glenn C. Morrison

Patents

Coating compositions and methods for using the same are disclosed. The coating compositions can include an aminosilica adsorbent. The coating compositions can adsorb CO2.

Go to article

Highly Stretchable And Sensitive Sbs/Gr/Cnts Fibers With Hierarchical Structure For Strain Sensors, Mengsui Liu, Yaping Sheng, Chenggang Huang, Chenggang Huang, Yanfen Zhou, Liang Jiang, Mingwei Tian, Shaojuan Chen, Stephen Jerrams, Fenglei Zhou, Jianyong Yu Jan 2023

Highly Stretchable And Sensitive Sbs/Gr/Cnts Fibers With Hierarchical Structure For Strain Sensors, Mengsui Liu, Yaping Sheng, Chenggang Huang, Chenggang Huang, Yanfen Zhou, Liang Jiang, Mingwei Tian, Shaojuan Chen, Stephen Jerrams, Fenglei Zhou, Jianyong Yu

Articles

Most of the reported flexible strain sensors can only normally sense external stretch in a quite narrow working range and with low sensitivity. In order to overcome these drawbacks, elastomeric fiber based strain sensors incorporating graphene (Gr) and carbon nanotubes (CNTs) were initially fabricated via coaxial wet spinning. The solution etching method was employed for forming a 1D@2D@1D hierarchical structure, with pores and microcracks on fibers, to reconstruct their conductive networks. The solution etched fiber based strain sensors achieved a significant improvement in obtaining a high maximum gauge factor of 1667 and capability of working over a wide strain range …

Go to article

Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson Jan 2023

Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson

Datasets

In this study, a thermal-economic analysis was conducted to determine the optimum insulation thickness of retrofitted insulation walls in different regions in Ireland. This was based on the Heating Degree Day method (HDD). This dataset contains optimum insulation thickness, payback period, cost savings and carbon emission for all 25 counties in the Republic of Ireland

Go to article

Fem Eem Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony Robinson Dr. Jan 2023

Fem Eem Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony Robinson Dr.

Datasets

A large number of combinations of Irish wall types, insulation materials, and heating fuel types were produced to compare the multiple variables which influence Optimal Insulation Thickness values. The total cost (TC) and carbon emission (CE) at optimum insulation thickness (OIT) for all combinations of insulation material and three types of fuel are considered. The dataset presents OIT for solid wall, cavity wall and cavity block wall types located in Monaghan, Dublin, and Kerry.

Go to article

Microstructure, Mechanical Properties And Oxidation Behavior Of Refractory Multi-Principal Element Alloys By Laser Remelting And Conventional Manufacturing, Visharad Jalan, Seth Crawford, Sung Heng Wu, Frank W. Liou, Haiming Wen Jan 2023

Microstructure, Mechanical Properties And Oxidation Behavior Of Refractory Multi-Principal Element Alloys By Laser Remelting And Conventional Manufacturing, Visharad Jalan, Seth Crawford, Sung Heng Wu, Frank W. Liou, Haiming Wen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Refractory Multi-Principal Element Alloys (RMPEAs), HfNbTaTiZr, (HfNbTaTiZr)9Cr, and (HfNbTaTiZr)9Al, Were Manufactured using Vacuum Arc Melting Followed by Laser Remelting to Mimic Additive Manufacturing. the Microhardness of the As-Cast HfNbTaTiZr, (HfNbTaTiZr)9Cr, and (HfNbTaTiZr)9Al Samples after Arc Melting Was Measured as 6.20, 7.63, and 6.89 Gpa, respectively. after Laser Remelting and Re-Solidification, the Hardness Increased by ~ 30% for Each Composition; the Hardest Was (HfNbTaTiZr)9Cr Measured at 9.60 GPa, While the Softest Was HfNbTaTiZr with a Hardness of 8.42 GPa, Which Was Still Harder Compared to All the Other Samples. the Addition …

Go to article

Impact Of Alumina-Based Binder On Formation Of Dense Strontium Zirconate Ceramics, Janos E. Kanyo, R. Sharon Uwanyuze, Jiyao Zhang, Rainer Hebert, Stefan Schafföner, Lesley Frame Jan 2023

Impact Of Alumina-Based Binder On Formation Of Dense Strontium Zirconate Ceramics, Janos E. Kanyo, R. Sharon Uwanyuze, Jiyao Zhang, Rainer Hebert, Stefan Schafföner, Lesley Frame

Materials Science and Engineering Faculty Research & Creative Works

Strontium zirconate (SrZrO3) is a technical ceramic with potential for refractory applications due to its chemical stability at high temperatures, high melting temperature, and favorable thermal expansion coefficient. Practical use of SrZrO3 is limited by poor mechanical strength relative to ceramics such as alumina (Al2O3). Sintering of SrZrO3 with a hydratable Al2O3 binder is investigated as a method for improving mechanical performance. Density, phase composition, thermomechanical properties, and chemical stability in contact with alloys up to 1350 °C are considered. Results are compared with SrZrO3 samples formed using a traditional polyvinyl alcohol (PVA) binder. SrZrO3 reacts with alumina during sintering …

Go to article

In Situ And Real-Time Mold Flux Analysis Using A High-Temperature Fiber-Optic Raman Sensor For Steel Manufacturing Applications, Bohong Zhang, Hanok Tekle, Ronald J. O'Malley, Todd Sander, Jeffrey D. Smith, Rex E. Gerald, Jie Huang Jan 2023

In Situ And Real-Time Mold Flux Analysis Using A High-Temperature Fiber-Optic Raman Sensor For Steel Manufacturing Applications, Bohong Zhang, Hanok Tekle, Ronald J. O'Malley, Todd Sander, Jeffrey D. Smith, Rex E. Gerald, Jie Huang

Materials Science and Engineering Faculty Research & Creative Works

Continuous Casting in Steel Production Uses Specially Developed Oxyfluoride Glasses (Mold Fluxes) to Lubricate a Mold and Control the Solidification of the Steel in the Mold. the Composition of the Flux Impacts Properties, Including Basicity, Viscosity, and Crystallization Rate, All of Which Affect the Stability of the Casting Process and the Quality of the Solidified Steel. However, Mold Fluxes Interact with Steel during the Casting Process, Resulting in Flux Chemistry Changes that Must Be Considered in the Flux Design. Currently, the Chemical Composition of Mold Flux Must Be Determined by Extracting Flux Samples from the Mold during Casting and Then …

Go to article

Comparison Of The Thermal Stability In Equal-Channel-Angular-Pressed And High-Pressure-Torsion-Processed Fe–21cr–5al Alloy, Maalavan Arivu, Andrew Hoffman, Jiaqi Duan, Jonathan Poplawsky, Xinchang Zhang, Frank W. Liou, Rinat Islamgaliev, Ruslan Valiev, Haiming Wen Jan 2023

Comparison Of The Thermal Stability In Equal-Channel-Angular-Pressed And High-Pressure-Torsion-Processed Fe–21cr–5al Alloy, Maalavan Arivu, Andrew Hoffman, Jiaqi Duan, Jonathan Poplawsky, Xinchang Zhang, Frank W. Liou, Rinat Islamgaliev, Ruslan Valiev, Haiming Wen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nanostructured Steels Are Expected to Have Enhanced Irradiation Tolerance and Improved Strength. However, They Suffer from Poor Microstructural Stability at Elevated Temperatures. in This Study, Fe–21Cr–5Al–0.026C (Wt%) Kanthal D (KD) Alloy Belonging to a Class of (FeCrAl) Alloys Considered for Accident-Tolerant Fuel Cladding in Light-Water Reactors is Nanostructured using Two Severe Plastic Deformation Techniques of Equal-Channel Angular Pressing (ECAP) and High-Pressure Torsion (HPT), and their Thermal Stability between 500–700 °C is Studied and Compared. ECAP KD is Found to Be Thermally Stable Up to 500 °C, Whereas HPT KD is Unstable at 500 °C. Microstructural Characterization Reveals that ECAP KD …

Go to article

Towards A Prototype Paleo-Detector For Supernova Neutrino And Dark Matter Detection, Emilie Marie Lavoie-Ingram Jan 2023

Towards A Prototype Paleo-Detector For Supernova Neutrino And Dark Matter Detection, Emilie Marie Lavoie-Ingram

UNF Graduate Theses and Dissertations

Using ancient minerals as paleo-detectors is a proposed experimental technique expected to transform supernova neutrino and dark matter detection. In this technique, minerals are processed and closely analyzed for nanometer scale damage track remnants from nuclear recoils caused by supernova neutrinos and possibly dark matter. These damage tracks present the opportunity to directly detect and characterize the core-collapse supernova rate of the Milky Way Galaxy as well as the presence of dark matter. Current literature presents theoretical estimates for these potential tracks, however, there is little research investigating the experimental feasibility of this technique. At the University of North Florida, …

Go to article

A Study On The Impact Of Silicon And Manganese On Peritectic Behavior In Low Alloy Steels Assisted By Mold Thermal Mapping Technology And Shell Growth Measurements, Damilola Balogun, Muhammad Roman, Rex E. Gerald, Laura Bartlett, Jie Huang, Ronald J. O'Malley Jan 2023

A Study On The Impact Of Silicon And Manganese On Peritectic Behavior In Low Alloy Steels Assisted By Mold Thermal Mapping Technology And Shell Growth Measurements, Damilola Balogun, Muhammad Roman, Rex E. Gerald, Laura Bartlett, Jie Huang, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Non-Uniform Shell Growth Commonly Caused by the Peritectic Transformation in Low Carbon and Low Alloy Steels Has Been Directly Correlated with Mold Thermal Maps using a Mold Immersion Test into a Molten Steel Alloy. Mold Thermal Maps Were Obtained by Performing Real-Time Temperature Measurements with Optical Fibers Embedded 1 Mm from the Mold Working Surface. Shell Growth Measurements Were Obtained by 3D Optical Scanning of the Recovered Steel Shell Following Immersion Testing. the Effects of Silicon and Manganese on the Shell Growth and Mold Temperature Maps Have Been Examined in Relation to the Peritectic Transformation for Varying Carbon Contents. Results …

Go to article

Oxidation Behavior Of Nb-Coated Zirconium Diboride, Jan E. Förster, William Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju Jan 2023

Oxidation Behavior Of Nb-Coated Zirconium Diboride, Jan E. Förster, William Fahrenholtz, Gregory E. Hilmas, Ravisankar Naraparaju

Materials Science and Engineering Faculty Research & Creative Works

Metallic Nb-Coatings Were Deposited on Top of ZrB2 by Means of Magnetron Sputtering to Improve its Oxidation Resistance. High Temperature Oxidation Tests Have Revealed that the Metallic Nb-Coatings Lead to the Formation of a Dense Solid and Protective Reaction Zone in Addition to a More Stable B2O3 Liquid Solution at the Surface. Compared to Baseline ZrB2, a Reduction in the Oxidation Kinetics, as Well as the Thickness of the Porous Zirconia Layer by 71%, Has Been Achieved with the Help of Nb-Coatings. a Liquid Phase Sintering by Molten Nb2O5 Mechanism Was …

Go to article

The Angiogenic Potential Of Ph-Neutral Borophosphate Bioactive Glasses, Bradley A. Bromet, Nathaniel P. Blackwell, Nada Abokefa, Parker Freudenberger, Rebekah L. Blatt, Richard K. Brow, Julie A. Semon Jan 2023

The Angiogenic Potential Of Ph-Neutral Borophosphate Bioactive Glasses, Bradley A. Bromet, Nathaniel P. Blackwell, Nada Abokefa, Parker Freudenberger, Rebekah L. Blatt, Richard K. Brow, Julie A. Semon

Materials Science and Engineering Faculty Research & Creative Works

Borate bioactive glasses have gained attention in recent years due to their therapeutic and regenerative effects in vivo. However, borate bioactive glasses release alkaline ions, increasing the local pH and creating a toxic environment for cell culture studies. A partial compositional substitution of phosphate for borate can create a pH-neutral glass that does not significantly affect the local pH while still releasing therapeutic ions. In the present study, a series of Na-Ca-borophosphate bioactive glasses with different borate-to-phosphate ratios was evaluated in vitro and in vivo for cytotoxicity and angiogenic effects. Compared to more basic borate glasses, the pH-neutral glasses supported …

Go to article

High Temperature Dielectric Properties Of Calcium Zirconate, Alan Devoe, Hung Trinh, Fatih Dogan Jan 2023

High Temperature Dielectric Properties Of Calcium Zirconate, Alan Devoe, Hung Trinh, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The electrical properties of dense, high purity CaZrO3 discs, sintered at 1380°C with and without added ZrO2, were investigated up to 950°C. Dielectric constant, loss tangent, and electrical conductivity were measured from 25 to 725°C, and the real and imaginary impedances were measured between 800 and 950°C by impedance spectroscopy techniques. Dielectric constant increased by 8% above 300°C and loss tangent increased from.1% at 25°C to ∼2% above 300°C. Activation energy of electrical conductivity determined between 300°C and 950°C by alternative current (AC) and direct current (DC) measurements. These results indicate that CaZrO3 could be a useful dielectric material for …

Go to article

Intragranular Nanocomposite Powders As Building Blocks For Ceramic Nanocomposites, Ryan D. Dempsey, Xiaoqing He, Jonathan A. Scott, David W. Lipke Jan 2023

Intragranular Nanocomposite Powders As Building Blocks For Ceramic Nanocomposites, Ryan D. Dempsey, Xiaoqing He, Jonathan A. Scott, David W. Lipke

Materials Science and Engineering Faculty Research & Creative Works

A powder-based bottom-up processing scheme is introduced for the production of ceramic nanocomposites. Internal displacement reactions between solid solution powders and metallic reactants proceeding via gaseous intermediates are utilized to generate nanostructured building blocks for the synthesis of ceramic nanocomposites. Subsequent rapid sintering results in ceramic nanocomposites, whose microstructures are inherited from the building blocks. This processing scheme is demonstrated for the production of titanium carbide nanocomposites featuring up to 28 wt.% intragranular tungsten inclusions derived from titanium-tungsten mixed carbide powders. Heat treatment of mixed carbide powders in evacuated ampoules containing titanium sponge and iodine at 1000°C for 24 h …

Go to article

Synthesis, Densification, And Cation Inversion In High Entropy (Co,Cu,Mg,Ni,Zn)Al2o4 Spinel, Cole A. Corlett, Nina Obradovic, Jeremy Lee Watts, Eric W. Bohannan, William Fahrenholtz Jan 2023

Synthesis, Densification, And Cation Inversion In High Entropy (Co,Cu,Mg,Ni,Zn)Al2o4 Spinel, Cole A. Corlett, Nina Obradovic, Jeremy Lee Watts, Eric W. Bohannan, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

The synthesis, densification behavior, and crystallographic site occupancy were investigated for four different spinel-based ceramics, including a high-entropy spinel (Co0.2Cu0.2Mg0.2Ni0.2 Zn0.2)Al2O4. Each composition was reacted to form a single phase, but analysis of X-ray diffraction patterns revealed differences in cation site occupancy with the high-entropy spinel being nearly fully normal. Densification behavior was investigated and showed that fully dense ceramics could be produced by hot pressing at temperatures as low as 1375°C for all compositions. Vickers' hardness values were at least 10 GPa for all compositions. The …

Go to article

Performance Evaluation Of Composite Sandwich Structures With Additively Manufactured Aluminum Honeycomb Cores With Increased Bonding Surface Area, M. Rangapuram, S. K. Dasari, Joseph William Newkirk, K. Chandrashekhara, H. Misak, P. R. Toivonen, D. Klenosky, T. Unruh, J. Sam Jan 2023

Performance Evaluation Of Composite Sandwich Structures With Additively Manufactured Aluminum Honeycomb Cores With Increased Bonding Surface Area, M. Rangapuram, S. K. Dasari, Joseph William Newkirk, K. Chandrashekhara, H. Misak, P. R. Toivonen, D. Klenosky, T. Unruh, J. Sam

Materials Science and Engineering Faculty Research & Creative Works

Modern aerostructures, including wings and fuselages, increasingly feature sandwich structures due to their high-energy absorption, low weight, and high flexural stiffness. The face sheet of these sandwich structures are typically thin composite laminates with interior honeycombs made of Nomex or aluminum. Standard cores are structurally efficient, but their design cannot be varied throughout the structure. With additive manufacturing (AM) technology, these core geometries can be altered to meet the design requirements that are not met in standard honeycomb cores. This study used a modified aluminum honeycomb core, with increased surface area on the top and bottom, as the core material …

Go to article

Final-Stage Densification Kinetics Of Direct Current–Sintered Zrb2, Austin D. Stanfield, Steven M. Smith, Suzana Filipović, Nina Obradović, Vladimir Buljak, Gregory E. Hilmas, William Fahrenholtz Jan 2023

Final-Stage Densification Kinetics Of Direct Current–Sintered Zrb2, Austin D. Stanfield, Steven M. Smith, Suzana Filipović, Nina Obradović, Vladimir Buljak, Gregory E. Hilmas, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

Final-stage sintering was analyzed for nominally phase pure zirconium diboride synthesized by borothermal reduction of high-purity ZrO2. Analysis was conducted on ZrB2 ceramics with relative densities greater than 90% using the Nabarro–Herring stress–directed vacancy diffusion model. Temperatures of 1900°C or above and an applied uniaxial pressure of 50 MPa were required to fully densify ZrB2 ceramics by direct current sintering. Ram travel data were collected and used to determine the relative density of the specimens during sintering. Specimens sintered between 1900 and 2100°C achieved relative densities greater than 97%, whereas specimens sintered below 1900°C failed to …

Go to article

Morphological And Structural Characterization Of Mgal2o4 Spinel, Nina Obradović, Suzana Filipović, William Fahrenholtz, Bojan A. Marinkovic, Jelena Rogan, Steva Lević, Antonije Đorđević, Vladimir B. Pavlović Jan 2023

Morphological And Structural Characterization Of Mgal2o4 Spinel, Nina Obradović, Suzana Filipović, William Fahrenholtz, Bojan A. Marinkovic, Jelena Rogan, Steva Lević, Antonije Đorđević, Vladimir B. Pavlović

Materials Science and Engineering Faculty Research & Creative Works

Magnesium aluminate has the spinel structure along with good mechanical, chemical, and thermal properties. Magnesium aluminate has a wide range of applications including refractory ceramics, optically transparent ceramic windows, and armors. Its low dielectric permeability and low loss tangent enable its applications for integrated electronic devices, as well. In this paper, MgO and Al2O3 powders were mixed in a one-to-one molar ratio and calcined at temperatures ranging from 1500 to 1800o C to produce phase pure spinel. Thereafter, pellets were crushed and treated in a planetary ball mill for 60 min to obtain a fine powder. All …

Go to article

Antioxidant Theranostic Copolymer-Mediated Reduction In Oxidative Stress Following Traumatic Brain Injury Improves Outcome In A Mouse Model, Aria W. Tarudji, Connor C. Gee, Hunter A. Miller, Rylie Steffen, Evan T. Curtis, Aaron M. Priester, Anthony J. Convertine, Forrest M. Kievit Jan 2023

Antioxidant Theranostic Copolymer-Mediated Reduction In Oxidative Stress Following Traumatic Brain Injury Improves Outcome In A Mouse Model, Aria W. Tarudji, Connor C. Gee, Hunter A. Miller, Rylie Steffen, Evan T. Curtis, Aaron M. Priester, Anthony J. Convertine, Forrest M. Kievit

Materials Science and Engineering Faculty Research & Creative Works

Following a traumatic brain injury (TBI), excess reactive oxygen species (ROS) and lipid peroxidation products (LPOx) are generated and lead to secondary injury beyond the primary insult. A major limitation of current treatments is poor target engagement, which has prevented success in clinical trials. Thus, nanoparticle-based treatments have received recent attention because of their ability to increase accumulation and retention in damaged brain. Theranostic neuroprotective copolymers (NPC3) containing thiol functional groups can neutralize ROS and LPOx. Immediate administration of NPC3 following injury in a controlled cortical impact (CCI) mouse model provides a therapeutic window in reducing ROS levels at 2.08–20.83 …

Go to article

The Effect Of Crystal Anisotropy On Fracture Toughness And Strength Of Zrb2 Microcantilevers, Tamás Csanádi, Ahmad Azizpour, Marek Vojtko, William Fahrenholtz Jan 2023

The Effect Of Crystal Anisotropy On Fracture Toughness And Strength Of Zrb2 Microcantilevers, Tamás Csanádi, Ahmad Azizpour, Marek Vojtko, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

The influence of crystal anisotropy on the micromechanical properties of ceramic grains plays an important role in the design of the macromechanical performance of bulk polycrystalline samples. To this end, the effect of crystal orientation on fracture toughness and strength was investigated by microcantilever bending experiments combined with finite element method (FEM) simulations in grains of a polycrystalline ZrB2 sample. The sample was prepared by hot pressing and the crystal orientations were determined by electron backscatter diffraction after careful surface preparation. The bending tests were carried out on notched and unnotched microcantilevers cut from specific grains along the prismatic (⊥ …

Go to article

Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen Jan 2023

Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

This report presents an additive manufacturing approach, for the first time, to producing high-entropy oxides (HEOs) using a 3D extrusion-based technique with oxide precursors. The precursors were prepared by a wet chemical method from sulfates. Additives were utilized to optimize the rheological properties of the printing inks with these precursors, and the properties of the printed HEOs were improved by increasing the solid content of the inks. When ink with a solid content of 78 wt% was used for printing, the resulting HEO exhibited a relative density of 92% and a high dielectric constant after undergoing pressure less sintering at …

Go to article

First Prev Next Last