Materials Science and Engineering Commons^™

Synthesis And Application Of Ceramic Paste For High-Temperature Electronic Packaging, Ardalan Nasiri

Graduate Theses and Dissertations

This dissertation research focused on the synthesis and application of ceramic paste for high-temperature applications. An alumina paste material comprising aluminum dihydric phosphate and alumina powder was developed for high-temperature electronic packaging. Nano aluminum nitride and nano-silica powders were embedded to promote the paste curing process, limit the grain growth, and increase its bond shear strength. The chip-to-substrate bond strength was enhanced and met the MIL-STD requirements for die-attach assembly. Its encapsulation property was improved with fewer cracks compared to similar commercial ceramic encapsulants. The die-attach material and encapsulation properties tested at 500°C showed no defect or additional cracks. Thermal …

Simultaneous Effects Of Rice Husk Silica And Silicon Carbide Whiskers On The Mechanical Properties And Morphology Of Sodium Geopolymer, Akm Rahman, Chirag Shah, Nihkil Gupta

Publications and Research

The current research is focused on developing a geopolymer binder using rice husk ash–derived silica nanoparticles. Four types of rice husks were collected directly from various rice fields of Bangladesh in order to evaluate the pozzolanic activity and compatibility of the derived rice husk ashes with precursors of sodium-based geopolymers. Silicon carbide whiskers were introduced into sodium-based geopolymers in order to evaluate the response of silicon carbide whiskers to the interfacial bonding and strength of sodium-based geopolymers along with rice husk ashes. Compression, flexural and short beam shear tests were performed to investigate the synergistic effect of rice husk ashes–derived …

Investigation Of Ceramic Firing Processes For Investment Casting Shell Molds, Leonardo Ken Hoaakua Nakamura, Rileigh Anne Cotter

Materials Engineering

PCC Structurals aims to improve the quality and consistency of their ceramic mold production for their investment casting processes to decrease product loss figures. Although their current production processes result in acceptable quantities of high-quality molds, a significant percentage of defective molds are produced. These defective molds cause appreciable product loss due to casting defects and mold failure. Available literature dictates that high-quality investment casting molds must exhibit fracture strengths within a desired range in order to perform adequately. However, information regarding specific firing procedures which consistently result in ceramic mold strengths within this range is not readily available. To …

Tension-Tension Fatigue Behavior Of Nextel™ 720/Alumina-Mullite Ceramic Composite At 1200°C In Air And In Steam, Sarah A. Witzgall

Theses and Dissertations

Uniaxial tension-tension fatigue performance of an oxide-oxide continuous fiber ceramic composite was studied at 1200°C in laboratory air and in steam. The composite is reinforced with laminated, 0/90 mullite/alumina (NEXTEL™720) fibers woven in an eight-harness satin weave and has a porous alumina/mullite matrix. There is no interphase between the fiber and matrix. The composite relies on the porous matrix for crack deflection and flaw tolerance. Tension-tension fatigue was examined for maximum stresses of 45 – 136 MPa in air and in steam. To assess the effects of the steam environment on fatigue performance, experimental results obtained in air are compared …

Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha

Materials Science and Engineering Faculty Research & Creative Works

Froth flotation process is extensively used for selective separation of base metal sulfides from uneconomic mineral resources. Reliable prediction of process outcomes (metal recovery and grade) is vital to ensure peak performance. This work employs an innovative hybrid machine learning (ML) model—constructed by combining the random forest model and the firefly algorithm—to predict froth flotation efficiency of galena and chalcopyrite in relation to various experimental process parameters. The hybrid model's prediction performance was rigorously evaluated and compared against four different standalone ML models. The outcomes of this study illustrate that the hybrid ML model has the prediction ability to process …

Empirical Modeling Of Structural Distortions In Perovskite Ceramics, Evan Connor Smith

Boise State University Theses and Dissertations

Predictive models for composition-structure-property relationships are essential to realizing the full potential of electroceramic materials; however, the electroceramics industry has largely failed to invest in predictive models in favor of simple rules of thumb or expensive, time-consuming trial-and-error methods. Empirically derived predictive models have the potential to significantly improve and guide future research in a more cost-effective and timely manner. It may even be possible to predict some intrinsic properties (e.g., polarization) on the order of a unit cell using only the charge and size of each chemical component. Scientists and researchers may ultimately be able to use …

Loading Orientation Dependence On The Compressive Response Of Ice-Templated Ceramic-Polymer Composites, Sashanka Akurati, Justine Marin, Dipankar Ghosh

College of Engineering & Technology (Batten) Posters

Natural materials are made from weak constituents, yet exhibit an excellent synergy of high stiffness, strength, and damage-tolerance. They consist of alternate layers of the hard and soft phases with a complex hierarchical structural organization. The ice-templating technique provides an approach to fabricate multilayered architectures for engineering applications. In this technique, an aqueous ceramic suspension is solidified unidirectionally leading to phase separation into alternating layers of ice-crystals and ceramic particles. Ice-crystals are sublimated by freeze-drying process and resultant ceramic foams are sintered to impart strength. The fabricated sintered ceramic foams contain alternate layers of oriented ceramic lamella walls and pores. …

Development Of B-Type And Multi-Ion Doped Carbonated Hydroxyapatite Bioceramics, Safarzadeh Marjan

Student Works (2020-2029)

The present research is aimed to investigate the effect of varying the carbonate to phosphate (CO32−/ PO43‒) molar ratios from 0.5 to 5 on the physical and mechanical properties of carbonated hydroxyapatite (CHA) synthesized by a wet chemical method. The sintering was performed under dry carbon dioxide atmosphere at 900 °C to maintain the B-type CHA structure. It was found that increases in CO32−/ PO43‒ ratio was accompanied by an increase in the c/a lattice ratio. The diffraction peaks of the synthesized 0.5-5 CHA powders exhibited a single phase material except for 5CHA which revealed the some minor calcite or …

Synthesis Of Sic Resin For 3d Printing Of Sic Ceramics By Digital Light Processing, Kevin Zhao, Bai Cui

UCARE: Research Products

Silicon carbide (SiC) resin is produced through shear mixing 0.1-1 μm SiC powders with Tethon’s high load Genesis resin base. Resins of varying SiC vol.% were synthesized to test the loading limit of the resin base; 10, 20, and 30 vol.% of SiC were made with the resin base handling the higher loads quite well. Several attempts were made at printing using the Tethon Bison 1000 DLP printer with higher loads of SiC showing better results even with lower intensity UV lights andtimes.

Cyclic Regeneration Of Nanostructured Composites For Catalytic Applications, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A cermet catalyst material, defining a matrix having interconnected open pores, the matrix selected from the group consisting of YSZ and CGO and defining a substrate, a ceramic coating having a general formula A_yB_nO_x at least partially coating the pores, and a plurality of metal particles A at least partially embedded in the ceramic coating. A is selected from the group consisting of Co, Cu, Ce, Ni, Ti, and combinations thereof and B is selected from the group consisting of Mo, W, Ce, and combinations thereof. When the coating is in a first oxidizing atmosphere …

Fatigue Behavior Of An Advanced Melt-Infiltrated Sic/Sic Composite With Environmental Barrier Coating At 1200°C In Air And In Steam, Thaddeus M. Williams

Theses and Dissertations

Advanced aerospace applications such as aircraft turbine engine components, hypersonic flight vehicles, and spacecraft reentry thermal protection systems require structural materials that have superior long-term mechanical properties under high temperature, high pressure, and varying environmental factors, such as moisture. Because of their low density, high strength and fracture toughness at high temperatures SiC fiber-reinforced SiC matrix composites are being evaluated for aircraft engine hot-section components. In these applications the composites will be subjected to various types of mechanical loadings at elevated temperatures in oxidizing environments. Because their constituents are intrinsically oxidation-prone, the most significant problem hindering SiC/SiC composites is oxidation …

Studying The Effects Of Various Process Parameters On Early Age Hydration Of Single- And Multi-Phase Cementitious Systems, Rachel Cook

Doctoral Dissertations

”The hydration of multi-phase ordinary Portland cement (OPC) and its pure phase derivatives, such as tricalcium silicate (C₃S) and belite (ß-C₂S), are studied in the context varying process parameters -- for instance, variable water content, water activity, superplasticizer structure and dose, and mineral additive type and particle size. These parameters are studied by means of physical experiments and numerical/computational techniques, such as: thermodynamic estimations; numerical kinetic-based modelling; and artificial intelligence techniques like machine learning (ML) models. In the past decade, numerical kinetic modeling has greatly improved in terms of fitting experimental, isothermal calorimetry to kinetic-based modelling …

Densification Of Ultra-Refractory Transition Metal Diboride Ceramics, William Fahrenholtz, Greg Hilmas, Ruixing Li

Materials Science and Engineering Faculty Research & Creative Works

The densification behavior of transition metal diboride compounds was reviewed with emphasis on ZrB₂ and HfB₂. These compounds are considered ultra-high temperature ceramics because they have melting temperatures above 3000°C. Densification of transition metal diborides is difficult due to their strong covalent bonding, which results in extremely high melting temperatures and low self-diffusion coefficients. In addition, oxide impurities present on the surface of powder particles promotes coarsening, which further inhibits densification. Studies prior to the 1990s predominantly used hot pressing for densification. Those reports revealed densification mechanisms and identified that oxygen impurity contents below about 0.5 wt% …

Doping With Rare Earth Elements And Resultant Nano-Inclusions On The Electrical And Thermal Properties Of The Mis-Fit Layered Thermoelectric Oxide, Geoffroy Gauneau

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thermoelectric generators produce electricity by directly converting temperature differences into electrical energy through Seebeck effect. Thermoelectric generators possess many unique features, such as having no moving part and being very reliable with a relatively long lifespan once built. They are solid-state waste heat harvesters. With various waste heat available throughout many industries, thermoelectric generators could offer economically competitive renewable energy. The current state of the art thermoelectric materials includes materials with relatively toxic elements and must work under vacuum, making them quite expensive to produce. Among the various thermoelectric materials, ceramic oxides have been proved to be more chemically stable …

Oxygen Transport Kinetics Of Surface Modified Mixed Conductor (La0.60sr0.40)0.95co0.20fe0.80o3-X As Solid Oxide Fuel Cell Cathode, Manuel Serrano Laguna

Graduate Theses, Dissertations, and Problem Reports (ETD)

The oxygen transport kinetics of the electrodes of Solid Oxide Fuel Cells (SOFC) are critical properties to achieve higher efficiencies in the cell. (La0.60Sr0.40)0.95Co0.20Fe0.80O3-x (LSCF) is a mixed ion-electron conductor material that is expected to be optimized and utilized as the cathode of the SOFC’s. The reason for LSCF to be considered as the next cathode material for SOFC is due to its high ionic and electronic conductivities, and high oxygen transport kinetics. Additionally, to the excellent properties that this material offers, it has been seen that the kinetic properties of the material can be further optimized by adding a …

Intrinsic Mechanical Properties Of Zirconium Carbide Ceramics, Nicole Mary Korklan

Masters Theses

“This research focuses on the processing and mechanical properties of zirconium carbide ceramics (ZrC_x). The first goal of this project was to densify near stoichiometric (i.e., x as close to 1 as possible) and nominally phase pure ZrC_x. The maximum stoichiometry achieved for the ZrC_x (C/Zr ratio of 0.92) was measured using gas fusion analysis. Hot pressing was used to obtain dense ZrC_x. Archimedes was used to determine the relative density of hot pressed ZrC_x at > 95%. Scanning electron microscopy (SEM) was used to determine the overall microstructure of the hot pressed …

Cyclic Regeneration Of Nanostructured Composites For Catalytic Applications, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A catalyst obtained by first preparing a cermet material with the general formula ABOx, wherein A is selected from the group consisting of Co, Cu, Ni, Ti, and combinations thereof, wherein B is selected from the group consisting of Mo, W, Ce, and combinations thereof, wherein A and B are different elements, and wherein x is a nonzero number ranging from 3 to 7 and represents the moles of O. Next, the cermet is activated in a reducing atmosphere to yield metal particles dispersed within and/or on the cermet.

Effect Of Incorporating Pottery And Bottom Ash As Partial Replacement Of Cement, Bassam A. Tayeh, Doha M. Alsaffar, Lawend K. Askar, Asmahan Issa Jubeh

Karbala International Journal of Modern Science

This study addressed the environmental constraints in cement produc­tion. Ordinary Portland cement (OPC) was replaced with pottery powder (PP, produced by grinding locally available pottery) and bottom ash (BA) at 10%, 20% and 30% of cement mass. Moreover, 4% calcium chloride solution (CaCl₂.2H₂O) was used as mixing water. Material properties, such as standard consistency, setting time and compressive strength, were measured with different percentages of OPC replacement with PP and BA. Results indicated that the replacement with PP and BA increased the water demand to achieve the standard consistency. These results revealed that the strength evolution …

Study Of Amorphous Boron Carbide And Hydrogenated Boron Carbide Materials Using Molecular Dynamics And Hybrid Reverse Monte Carlo, Rajan Khadka

Graduate Theses/Dissertations

We present a computational study of amorphous boron carbide (a-B_xC) models using Molecular Dynamics (MD) studied with Stillinger-Weber (SW) and ReaxFF potential. The atomic structure factor (S(Q)), radial distribution function (RDF) and bond lengths comparison with other experimental and ab initio models shows that a random arrangement of icosahedra (B₁₂, B₁₁C) interconnected by chains (CCC, CBC) are present in a-B_xC. Afterward, Hybrid Reverse Monte Carlo (HRMC) technique is used to recreate a-B_xC structures. The existing SW potential parameters of Boron are optimized for the α-rhombohedral (Icosahedral B_{12 …}

Vanadium-Based Nanomaterials For Improved Zn Ion Storage, Jianwei Lai

LSU Master's Theses

Rechargeable aqueous zinc-ion batteries (ZIBs) have been intensively studied as novel promising large-scale energy storage systems recently, owing to their advantages of high abundance, cost effectiveness, and high safety. However, the development of suitable cathode materials with superior performance are severely hampered by the sluggish kinetics of Zn²⁺ with divalent charge in the host structure.

Our Work demonstrates boosting the electrochemical performances of nanostructured cathode materials for aqueous ZIBs. The first project is focused on the interlayer-expanded V₆O₁₃∙nH₂O nanosheets as promising cathodes. Benefiting from the synthetic merits of its favorable architecture and expanded …

Synthesis Of Amorphous Hydrogenated Boron Carbide From Orthocarborane Using Argon Bombardment: A Reaxff Molecular Dynamics Study, Nirmal Baishnab

Graduate Theses/Dissertations

In this study, the synthesis process of a-B­_xC:H_y using argon bombardment from the orthocarborane precursor was modeled by using reactive molecular dynamics (MD). Utilizing the MD simulations, the formation of free radicals as a result of ion bombardment was identified and quantified. Then, the densification process that is aided by the mixture of free radicals and orthocarborane was analyzed. The densification process by creating the initial structure composed of free radicals and orthocarborane with active sites created by partially removing some of the hydrogen atoms from the icosahedral cage was also modelled. Overall, a better understanding of …

Braze For Ceramic And Ceramic Matrix Composite Components, Sean E. Landwehr, Scott Nelson, Jeremy Lee Watts, Greg Hilmas, William Fahrenholtz, Derek Scott King

Materials Science and Engineering Faculty Research & Creative Works

In some examples, a technique may include positioning a first part comprising a ceramic or ceramic matrix composite and a second part comprising a ceramic or a CMC adjacent to each other to define a joint region at the interface of the first part and the second part. In some examples, the joint region may be heated using at least one of a laser or a plasma arc source to heat the joint region to an elevated temperature. The first and second parts may be pressed together and cooled to join the first and second parts at the joint region. …

Methods Of Use And Manufacture Of Silver-Doped, Nano-Porous Hydroxyapatite, Cheol-Woon Kim, Richard K. Brow

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A silver-doped, nano-porous hydroxyapatite material is provided that can be utilized to capture radioactive iodine, ¹²⁹I. Methods of using the silver-doped, nano-porous hydroxyapatite material to remove radioactive iodine, and methods of manufacturing the material are also provided.

Bioprinting With Human Stem Cell-Laden Alginate-Gelatin Bioink And Bioactive Glass For Tissue Engineering, Krishna C. R. Kolan, Julie A. Semon, Bradley Bromet, D. E. Day, Ming-Chuan Leu

Biological Sciences Faculty Research & Creative Works

Three-dimensional (3D) bioprinting technologies have shown great potential in the fabrication of 3D models for different human tissues. Stem cells are an attractive cell source in tissue engineering as they can be directed by material and environmental cues to differentiate into multiple cell types for tissue repair and regeneration. In this study, we investigate the viability of human adipose-derived mesenchymal stem cells (ASCs) in alginate-gelatin (Alg-Gel) hydrogel bioprinted with or without bioactive glass. Highly angiogenic borate bioactive glass (13-93B3) in 50 wt% is added to polycaprolactone (PCL) to fabricate scaffolds using a solvent-based extrusion 3D bioprinting technique. The fabricated scaffolds …

Erosion Resistance Of Tungsten-Carbide Coatings For Steel Pipes In Fluid Catalytic Cracking Units, Davis Vannasing, Jennifer Hulfachor

Materials Engineering

In petroleum processing, the flow of catalyst readily leads to erosion of piping in a fluid catalytic cracking unit. Advances in coating materials and processes necessitate a re-evaluation of current protection methods. Commercially available tungsten-carbide (WC) claddings and nanostructured WC-W CVD coatings were investigated as potential alternative erosion-resistant coatings. Erosion tests by solid particle impingement were conducted on 2 variations of claddings and 1 variation of WC-W coatings following ASTM standard G76. A36 steel coupons were used as reference samples. For statistical validation, 2-3 replications of the tests were performed for the claddings and WC-W coating. Testing was conducted using …

Investigation Of Copper Infiltration Alloys For Use In Metal Matrix Composite Drill Bits, Samuel J. Stueland, Timothy P. Markiewicz

Materials Engineering

A newly developed copper-based alloy, P98-X1 was tested for compressive strength to predict qualitative performance compared to MF53, F-Bronze, CuNiSn, and CuMnNi for use as the infiltration alloy in metal matrix composite (MMC) drill bits. Ingots of each alloy were cast using an arc furnace and cut into compression testing samples using wire electrical discharge machining (EDM). The alloys were selected for testing based on solid solution strengthening coefficient and melting point. Five of each alloy were compression tested to determine yield strength of the infiltration alloy. Yield strength was determined using a 0.002mm displacement offset from the linear elastic …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Fracture Toughness Improvement Of ����� Ceramics By Grain Size Control And Ductile Phase Reinforcement, Kesong Wang

McKelvey School of Engineering Graduate Student Theses & Dissertations

This study used grain size control and ductile phase reinforcement to improve fracture toughness of ����� ceramics. Alpha alumina particles of 100 nm, 0.5-1 micrometers, and 10 micrometers were coated with 1-5 nm nickel by electroless nickel plating (ENP). The coated powders were consolidated at 1200℃-1500℃ by spark plasma sintering (SPS). The sintered samples were annealed at 1100 oC for 1.5 hours and 10 hours to determine the effect of post sintering annealing on hardness and fracture toughness. Density of the samples were measured by the standard Archimedes method using a 5 mL pycnometer. Hardness values were determined by Vickers …

Plasma Oxidation Of Liquid Precursors For Complex Metal Oxides., Babajide Patrick Ajayi

Electronic Theses and Dissertations

Clean energy production and storage are two of the most significant challenges in the 21^st century currently limited by the discovery and development of new and advanced materials. Complex oxides and alloys made using earth-abundant elements will play a crucial role in technology development moving forward, however, current preparation techniques are limited by their inability to produce complex oxides and alloys with precise composition control at fast timescales. A concept was proposed to produce mixed metal oxides with composition control through the oxidation of liquid precursors via plasma oxidation. It was hypothesized that the oxidation process can be completed …

Synthesis And Characterization Of Dielectric And Multiferroic Nanocrystalline Transition Metal Oxide Materials And Nanocomposites, Frederick A. Pearsall

Dissertations, Theses, and Capstone Projects

Nanocrystalline transition metal oxides with unique chemical, physical, magnetic and dielectric properties have very broad applications, ranging from photocatalysis, capacitor energy storage and 4-state memory. Frequency stable, high permittivity nanocomposite capacitors produced under mild processing conditions offer an attractive replacement to MLCCs derived from conventional ceramic firing. In one project reported herein, 0-3 nanocomposites were prepared using BaTiO₃ (barium titanate, BTO) nanocrystals, suspended in a poly(furfuryl alcohol) matrix, resulting in a stable, high effective permittivity, low and stable loss dielectric. Effective medium approximations were used to compare this with similar nanocomposite systems. The use of synthesized BTO nanocrystal photocatalysts …