Materials Science and Engineering Commons^™

Oxidation Of Hafnium Diboride—Silicon Carbide At 1500 °C In Air; Effect Of Compressive Stress, Anthony J. Degregoria, Marina B. Ruggles-Wrenn, Glen E. Pry

Faculty Publications

The long-term oxidation behavior of HfB₂ and of HfB₂-20 vol.% SiC was studied. Test samples of each material were oxidized at 1500 °C in air using a box furnace. The exposure times were 0, 0.5, 1, 2, 3, 6, 9, 12, 15, 30, 45 and 90 h. Weight gain, oxide scale composition and oxide scale thickness were characterized for both materials. Crystal structure of the surface scales was analyzed using x-ray diffraction. Oxide scales were further characterized via scanning electron microscopy with energy dispersive spectroscopy analysis. For HfB₂ the oxide scale consists predominantly of porous HfO …

Multiscale Modeling And Gaussian Process Regression For Applications In Composite Materials, Joshua Arp

All Dissertations

An ongoing challenge in advanced materials design is the development of accurate multiscale models that consider uncertainty while establishing a link between knowledge or information about constituent materials to overall composite properties. Successful models can accurately predict composite properties, reducing the high financial and labor costs associated with experimental determination and accelerating material innovation. Whereas early pioneers in micromechanics developed simplistic theoretical models to map these relationships, modern advances in computer technology have enabled detailed simulators capable of accurately predicting complex and multiscale phenomena.

This work advances domain knowledge via two means: firstly, through the development of high-fidelity, physics-based finite …

Electrosteric Control Of The Aggregation And Yielding Behavior Of Concentrated Portlandite Suspensions, Sharu Bhagavathi Kandy, Narayanan Neithalath, Mathieu Bauchy, Aditya Kumar, Edward Garboczi, Torben Gaedt, Samanvaya Srivastava, Gaurav Sant

Materials Science and Engineering Faculty Research & Creative Works

Portlandite (calcium hydroxide: CH: Ca (OH)2) suspensions aggregate spontaneously and form percolated fractal aggregate networks when dispersed in water. Consequently, the viscosity and yield stress of portlandite suspensions diverge at low particle loadings, adversely affecting their processability. Even though polycarboxylate ether (PCE)-based comb polyelectrolytes are routinely used to alter the particle dispersion state, water demand, and rheology of similar suspensions (e.g., ordinary portland cement suspensions) that feature a high pH and high ionic strength, their use to control portlandite suspension rheology has not been elucidated. This study combines adsorption isotherms and rheological measurements to elucidate the role of PCE composition …

Synthesis And Characterization Of Cobalt(Iii) Complexes And A Vanadium(Iv) Complex With Flavonoids As Ligands, Ethan Schroeder

Chemistry & Biochemistry Theses & Dissertations

For many years now, transition metal complexes have been used as favorable additional chemotherapeutic approaches to medicine that were previously unexplored in the literature. One well-known chemotherapeutic drug, cisplatin, has been applied, but is limited in use due to its toxicity to the cells and its undesirable side effects to humans. Newly developed cobalt-based complexes with ligands known as flavonoids are being used to fight cancer. Flavonoids, compounds mainly found in fruits and vegetables, are shown to have antioxidative and anticancer properties. Use of flavonoids as ligands in transition metal complexes, e.g., those with a Ru(II) metal center, have been …

Integrating Sensor Development, Risk Assessment, And Community Engagement To Support Environmental Justice In The Rural Community Of El Tiple, Colombia, David Bahamon Pinzon

All Dissertations

In Colombia, ethnic communities have traditionally been responsible stewards of natural resources. They recognize the importance of these resources for their livelihood, as well as their ancestral and cultural heritage. El Tiple, a rural Afro-Colombian community, has been affected by the incursion of private corporations that promoted the expansion of sugarcane monocrops in their territory. Since the introduction of the monoculture industry, local freshwater sources have been depleted due to intensive water use for irrigation of the sugarcane crops. Additionally, the intensive usage of agrochemicals has been linked with loss of native flora, damages to family farms, and pollution of …

Double Cantilever Beam Mode-I Testing Validation In Large-Scale Additive Manufacturing Carbon Composite, Luis Alfonso Camacho

Open Access Theses & Dissertations

Testing for mechanical properties for additive manufacturing has been based on already existing standards for traditional manufacturing methods. For composites in large scale additive manufacturing there is a research gap in bond strength and fracture toughness for a single layer interface. By using Double cantilever beam Mode I, this thesis manuscript validates testing parameters and protocols to describe the intricacies of ABS matrix 20 wt.% carbon filled composite, specifically on the layer-to-layer interface. Studies suggest that fracture toughness is sensitive to process parameters, like deflection speed and sharpened crack tip at the layer interface of BAAM 3D printed part and …

Effect Of Heat Treatment On The Mechanical And Corrosion Properties Of The Cocrnifeal Heas, Ahmed Korra

Masters Theses and Doctoral Dissertations

High entropy alloys (HEAs) are a relatively new class of metallic materials that have shown great potential for use in extreme environments, such as high temperatures and corrosive conditions. Among the different types of HEAs, CoCrNiFeAl HEAs are potential materials for a wide range of applications, including aerospace, biomedical, and energy storage. This work focused on the effects of heat treatment temperatures from 800 °C to 1100 °C on the microstructure and mechanical properties of these alloys, as well as their electrochemical corrosion behavior. A thermodynamic model was implemented to predict the performance of the material. The results of this …

Magnesium-Based Nanocomposites: A Review From Mechanical, Creep And Fatigue Properties, S. Abazari, A. Shamsipur, H. R. Bakhsheshi-Rad, J. W. Drelich, J. Goldman, S. Sharif, A. F. Ismail, M. Razzaghi

Michigan Tech Publications

The addition of nanoscale additions to magnesium (Mg) based alloys can boost mechanical characteristics without noticeably decreasing ductility. Since Mg is the lightest structural material, the Mg-based nanocomposites (NCs) with improved mechanical properties are appealing materials for lightweight structural applications. In contrast to conventional Mg-based composites, the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability. The present article reviews Mg-based metal matrix nanocomposites (MMNCs) with metallic and ceramic additions, fabricated via both solid-based (sintering and powder metallurgy) and liquid-based (disintegrated melt deposition) technologies. It also reviews strengthening models and mechanisms that …

Preparation Of High Entropy Titanite Pyrochlore And Radiation Stability Study, Adam Gootgeld

All Theses

Pyrochlore has been studied as a host phase for safe storage of radionuclides and exists naturally with long-term stability with good long-range order [1]. High entropy oxides show promising tunable properties that could demonstrate favorable bulk deposit of radioactive materials such as spent nuclear fuel (Uranium and other actinides). It is proposed that using high entropy oxides (HEOs) as the cation in this framework will shift the gibbs free energy so that radioactive nuclear waste will be stabilized for safe, long-term, eco-friendly storage. We have established a consistent method to fabricate high entropy titanite pyrochlores. In this study, ion beam …

Computational And Experimental Study On Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis

Physics & Astronomy Faculty Publications

We present a combined density functional theory (DFT) and experimental work on lithium tantalate LiTaO3 (LT) and its Er-doped counterparts. We calculate the electronic and optical properties for both LT and LT:Er+3, with Er occupying either Li or Ta sites, at 4.167 mol%. The generalized gradient approximation (GGA) calculations show that the Er-4 f bands appear closer to the conduction band bottom and to the valance band top, for the first and second doped configurations, respectively. This agrees with changes in the imaginary part of the frequency dependent dielectric function between the doped configurations. There are striking differences between the …

Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady

All Theses

Polylactic acid (PLA) is a biopolymer made from renewable resources such as sugar and corn. PLA filament is a popular material used in Fused Deposition Modeling (FDM) 3D-printing. While this material has many advantages, all the failed parts, support structures, rafts, nozzle tests, and the many prototype iterations during the 3D-printing process contribute to the plastic pollution and release of greenhouse gases. Although PLA is biodegradable, it can take years to degrade in landfills. Instead of throwing away PLA waste and buying new filaments, PLA can be recycled. Amongst the different recycling technologies, mechanical recycling is the most environmentally friendly. …

Photophysical Studies Of Electronic Structure And Excited-State Dynamics Of Dna-Templated Cyanine Dye Aggregates, Jonathan Samuel Huff

Boise State University Theses and Dissertations

The invention and widespread adoption of the digital computer in the last century has led to an era of rapid technological advancement that has continued to the present day. This advancement has been sustained to a large degree by continued miniaturization of the electronic components in microprocessors, which results in increased computing power and energy efficiency. In recent years, this strategy has produced diminishing returns because the cost for each incremental size reduction increases as engineers approach the fundamental scaling limits of silicon-based semiconductor devices. Meanwhile, breakthroughs in DNA nanotechnology hold great promise for a new generation of self-assembled nanodevices …

Transformation Pathways Of Lanthanide-Free Mn-Al-Ga-X Alloys Where X = Co, Fe, And Ni, Shane L. Palmer

Boise State University Theses and Dissertations

Ubiquitous rare-earth, (i.e. lanthanide) permanent magnets (PMs) composed of Nd-Fe-B are the strongest PMs on the market. However, limited mineral sources, complex elemental separation, and supply chain volatility have shifted the lanthanides to critical material status. Inexpensive, readily available materials are sought to fill an energy product performance gap to reduce dependency on lanthanide PMs. Frequently, lanthanide PMs are used in applications where their energy products are excessively high. Mn-Al based permanent magnets offer a potential substitute for PM applications which do not require the high energy product of a lanthanide PM. MnAl alloys form a metastable ferromagnetic tetragonal …

Poly(Alkyl Aldehyde)S: A New Class Of Closed-Loop Recyclable Plastics, Kyle Arnold Nogales

Boise State University Theses and Dissertations

This dissertation will describe a new class of closed-loop recyclable, self-immolative polymers that undergo selective, complete, and rapid depolymerization in the solid state when triggered. Self-immolative poly(alkyl aldehyde)s are synthesized efficiently in approximately 60% yield using anionic polymerization, which provides access to polymers in accessible lengths ranging from short (M_n value of 2 kDa) to long polymers (M_n value of 5,000 kDa). The physical and thermal properties of the polymers can be tuned rationally by appropriate choice of the aldehyde monomer, with some of the polymers displaying mechanical properties that are similar to traditional plastics. The polymers depolymerize …

Development And Characterization Of Lead & Lead-Free Perovskite Solar Cell Materials, Rubaiya Murshed

UNLV Theses, Dissertations, Professional Papers, and Capstones

In recent years, perovskite photovoltaic technology has offered enormous viability and dimensionality in solar cell research. As a light-harvesting active layer, Perovskite generated remarkable development in device efficiency of 25.7% for the single-junction solar cell, and over 33% for the perovskite/silicon tandem solar cell. Also, perovskite-perovskite tandem solar cell (also called all-perovskite tandem solar cell) shows great potential in device performance and achieved a power conversion efficiency (PCE) of 26.4%. Transitioning photovoltaic technology from the laboratory to commercial products, high PCE, low cost, long lifetime, and low toxicity are some of the critical factors to consider during material selection. Pb-halide …

Carbon Fibers From Athabasca Oil-Sand Asphaltenes, Blake Reardon

All Theses

Carbon fibers possess ultra-high specific strength and modulus. Therefore, the material is popular in aerospace, automotive, and sports industries. Approximately 95% of all carbon fibers are spun from a high-cost precursor, polyacrylonitrile (PAN). There is a need for a cheaper grade of carbon fiber for low-cost applications because about half of carbon fiber cost is associated with precursor cost. A promising alternative to the high-cost PAN precursor is petroleum-based asphaltene. Asphaltenes are highly aromatic and have a high carbon content but lack the purity of the PAN precursor. Processes like the molten- sodium desulfurization upgrading have been used to harvest …

Processing, Microstructure, And Properties Of Alumina Ceramics And Silica Glass During Laser Selective Additive/Subtractive Manufacturing, Xiao Geng

All Dissertations

The heterogeneous structure is essential to obtain excellent performance in many ceramics or glass devices/components. Conventional fabrication on these heterogeneous structure composites usually requires multiple treatments, specific molds for certain structures, and post-processing to get desired structure and properties. Therefore, the flexibility of the structure is limited, and a long fabrication time is required.

Integrated additive/subtractive manufacturing and laser-based technologies have caught researchers` attention in ceramics/glass heterogeneous structure fabrication. This is because the integration of additive manufacturing (AM) with subtractive manufacturing (SM) not only maintained the advantages of AM in rapid prototyping, design complexity, and reduced material wastage but also …

Chemical And Physical Interaction Mechanisms And Multifunctional Properties Of Plant Based Graphene In Carbon Fiber Epoxy Composites, Daniel W. Mulqueen

Mechanical & Aerospace Engineering Theses & Dissertations

Graphene has generated substantial interest as a filler due to its exceptional strength, flexibility, and conductivity but faces obstacles in supply and implementation. A renewable, plant-based graphene nanoparticle (pGNP) presents a more accessible and sustainable filler with the same properties as mineral graphenes. In this study, the mechanisms of graphene reinforcement in carbon fiber reinforced plastic (CFRP) were examined, along with the resulting improvements to mechanical strength, resistance to crack propagation, electrical and thermal conductivity at elevated temperatures. pGNP, produced from renewable biomass, was shown to have a graphitic structure with flakes 3-10 layers thick and a median lateral size …

A Spike-Shaped Anchorage For Steel Reinforced Polymer (Srp)-Strengthened Concrete Structures, Xingxing Zou, Keenan L. Mcburney, Lesley H. Sneed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Steel reinforced polymer (SRP) composite has recently emerged as an effective and economical solution for strengthening of reinforced concrete (RC) structures. Premature debonding failure of unanchored SRP at low load levels generally governs the performance of RC structures strengthened with externally bonded SRP. Therefore, a novel yet simple spike-shaped anchorage system was proposed in this study to prevent the debonding failure of SRP and to improve the interfacial shear capacity. Experimental investigation through single-lap shear tests of SRP-concrete joints showed that the anchorage system changed the failure mode from composite debonding to fiber rupture. In addition, the anchorage system substantially …

Mechanical Properties Of Biocomposite With Various Composition Of Caco3 And Starch, Agris Setiawan, Fransisca Diana Wahyuningsih, Riria Zendy Mirahati

Journal of Mechanical Engineering Science and Technology (JMEST)

Calcium carbonate has the potential to be used in the development of medical materials, including biomaterials. Biocomposite is composed of CaCO3 as matrix material and bioplastic from the combination of corn starch and cassava starch as reinforcement. This study aims to determine mechanical properties such as tensile strength and bending/flexural strength with varying compositions of CaCO3 and bioplastic. Characterization of the biocomposite uses Scanning Electron Microscope to observe the microstructure and composition elements of their structure. This study used 4 variations in the ratio of CaCO3 suspension: (Corn Starch + Cassava Starch). Each sample was characterized using specimen code A …

Synthesis And Characterization Of Nitrogen-Doped Activated Carbon For Lithium Battery Anode Applications, Prihanto Trihutomo, Poppy Puspitasari, Muhammad Bustomi Radja, Milzam Rahmat Busono

Journal of Mechanical Engineering Science and Technology (JMEST)

Nitrogen-dopped activated carbon was synthesized to see its effect on the characterization of the nitrogen surface functional groups, crystal size, and morphology of the resulting sample. Synthesis of nitrogen-doped activated carbon was carried out by varying the addition of Urea as a nitrogen doping source. Activated carbon compared its characteristics with variations in the concentration of added Urea to activated carbon, at 1:3 and 1:5. The FTIR results obtained were the presence of functional groups indicating the presence of nitrogen bonds in each sample. The crystallinity results showed that the samples were classified as crystalline and nitrogen doping influenced the …

Designing A Naabsa Class Tanker Ship With Bottom Protection From Ground, Victor A. Kulesh, Mathias B. Prasetio, Fam Chung Hiep

Journal of Mechanical Engineering Science and Technology (JMEST)

Indonesia is the world's largest archipelago country with a high potential for economic development and top producer and exporter of palm oil. As an archipelago country, the most efficient cargo transportation routes are through rivers and seas. Designing and building tankers, taking into account the specifics of the operation, are relevant. The paper considers the issues of designing a tanker for the transportation of crude palm oil with a defined operation area and route. The general concept of the vessel is proposed, taking into account the restrictions on the navigation area and draft for operation in the river. Particular attention …

Effect Of Grafting Nano-Tio2 On Sansevieria Cylindrica Fiber Properties, Chrisrulita Sekaradi Wiguna, Heru Suryanto, Aminuddin Aminuddin, Jibril Maulana, Joseph Selvi Binoj, Alamry Ali

Journal of Mechanical Engineering Science and Technology (JMEST)

Natural fibers, which are abundant, environmentally friendly, and biodegradable, are used as a replacement for synthetic fibers. The composite strength can be increased by treating the surfaces of natural fibers with suitable chemicals, which can also improve the interface interaction between fiber and matrix. Application of a coupling agent in chemical treatment is utilized to reinforce the bonding between fiber and matrix. The objective of the study is to determine the influence of silane concentration on the Sansevieria cylindrica fiber properties. The methods included fibers treatment using ethanol and coupling agent as dissolving and TiO2 with concentrations of 0%, 0.25%, …

The Combustion Characteristics Of Calophyllum Inophyllum Fuel In The Presence Of Magnetic Field, Imam Rudi Sugara, Nasrul Ilminnafik, Salahuddin Junus, Muh Nurkoyim Kustanto, Yuni Hermawan

Journal of Mechanical Engineering Science and Technology (JMEST)

The study objective is to investigate the combustion characteristics of Callophyllum inophyllum fuel in presence of a magnetic fields. To conduct the experiment, a bunsen burner was utilized, with fuel and air being dispensed via a syringe pump and compressor, both regulated by a flowmeter. The fuel and air pipes were heated to 532.15 (K) to facilitate fuel evaporation. The equivalent ratio of 0.5, 1, and 1.5 was adjusted to control air discharge and fuel. An 11,000 gausses artificial magnet was used, with N-S, N-S, N-N, and SS being the various magnetic pole configurations. The study found that the magnetic …

Effect Of Current And Pulse-On Time On Material Removal Rate And Surface Roughness Of Tungsten Carbide In Electric Discharge Machine Die-Sinking, Mochamad Deny Riyanto, Andoko Andoko, Heru Suryanto

Journal of Mechanical Engineering Science and Technology (JMEST)

The focus of manufacturing for tungsten carbide applications often demands a smooth surface quality as the result of the Electric Discharge Machine (EDM) die-sinking process, especially in the manufacture of die and mold with tungsten carbide material processed using a die-sinking EDM machine. The purpose of this study is to analyze the effect of electric current and pulse-on time on the Material Removal Rate (MRR) and surface roughness of tungsten carbide. Through the experimental method, the parameters varied, namely electric current 17 A, 20 A, 23 A, and pulse-on time 30 µs, 55 µs, and 80 µs. MRR was calculated …

Lap Joint On St.37 Steel Plate With Friction Welding Clamping Method, Widia Setiawan, Nugroho Santoso, Wiyadi Wiyadi, Muhammad Sulistiyo Aji, Rachmat Alamin, Achsan Tarmudi

Journal of Mechanical Engineering Science and Technology (JMEST)

Friction stir (FW) welding is a relatively fresh method that was created and has been continually refined and adapted to industrial applications due to its benefits. This approach for solid-state joining entails connecting the components at a temperature below their melting point and then heating them up. Clamp joint applications are widely used using external heating and hitting with high strength, but the clamped joints with the FW method are rarely done. The research studied the characteristic of clamped joints at various plate thicknesses using the FW method. In this study, 30 specimens were used in the form of a …

The Effect Of Cutting Speed Of Nitrogen Laser Cutting On The Surface Texture Of Sus 304 Plate, Yanuar Rohmat Aji Pradana, Raka Afrianto, Chandra Hairat Abdul Rahman, Andoko Andoko

Journal of Mechanical Engineering Science and Technology (JMEST)

The focus of today’s machining industry is on how to maintain high productivity and low cost achieved by high tool life during the operation. Laser cutting is considered the right solution because it offers cutting speeds of up to 170000 mm/min through a non-contact process regardless of the workpiece material hardness. The aim of this study is to analyze the effect of cutting speed on the surface texture aspects namely surface roughness, kerf shape, and dross height on the stainless steel 304 plate after laser cutting. The nitrogen laser was utilized with the cutting speed of 400, 1700, and 2000 …

Analysis Of Fire And Smoke Spread In Ki Hajar Dewantara Auditorium, State University Of Jakarta, Using Fire Dynamics Simulator, Pratomo Setyadi, Ariq Harits Arrizq

Journal of Mechanical Engineering Science and Technology (JMEST)

Fire behavior and smoke spread are influenced by various factors, including the amount and condition of combustible material, ventilation openings, and ceiling height. A high amount of combustible material in the auditorium poses a significant fire hazard, hence, efforts need to be made to minimize the risk. One approach is to use Computational Fluid Dynamic software, such as Fire Dynamics Simulator (FDS), to model fire combustion. In this research, it provides an overview of the heat release rate (HRR) of fires that occur as well as the effect of differences in ceiling height and the effect of ventilation on fire …

Effect Of Temperature Variations Of Corn (Maize) Oil Biodiesel On Torque Values And Thermal Efficiency Of Diesel Engines, Suardi Suardi, Rodlian Jamal Ikhwani, Ade Putri Rezki Aulia

Journal of Mechanical Engineering Science and Technology (JMEST)

The trend of consumption of hydrocarbon fuels in Indonesia, which is increasing every year, is not accompanied by the amount of production, which is decreasing. Alternative fuels to reduce dependence on hydrocarbon fuels. One form of alternative fuel is biodiesel, which is made from corn (maize) oil. Corn oil itself, if processed, can be an option for clean and environmentally friendly energy option and that is the main objective of this research is to determine the performance of biodiesel corn oil on diesel engines. The method used in this study is an experimental method where corn oil biodiesel is tested …

Flow Through Processing Of Nanocellulose For Space Exploration Applications, Dylan Seiffert, T. E. Kidd

Summer Undergraduate Research Program (SURP) Symposium

Nanocellulose is synthesized from cellulose, which is the most abundant organic molecule found in nature. Nanocellulose solids are biodegradable and have a strength-to-weight ratio eight times that of steel¹. The production of nanocellulose solids is challenging due to the large volume loss that occurs during the curing process as well as the time and cost associated with ultrasonic processing. The loss of volume during curing often results in cracking and deformation of the cured solid. The issues caused by the large volume loss can be mitigated using additives that do not compromise the strength, shape, or machineability of …