Materials Science and Engineering Commons^™

Electrodeposition Of Tin Using Tin(Ii) Methanesulfonate From Mixture Of Ionic Liquid And Methane Sulfonic Acid., Yang Kok Kee

Student Works (2010-2019)

The electrodeposition of tin from Tin(II) Methane Sulfonate (MSA) with varying concentration in air and water stable 1-butyl-1-methyl-pyrrolidinium trifluoromethanesulfonate, (BMPOTF) ionic liquid at room temperature was studied. Cyclic Voltammetry served to characterize the electrochemical behavior of tin reduction and oxidation. The diffusion coefficient of stannous ions in the mixture of BMPOTF ionic liquid and MSA based electrolyte obtained via Randles-Sevcik and Cottrell equation was 2 × 10-7 cm2/s. Electroplating on copper panel was conducted under different current densities to determine BMPOTF based tin plating solution current efficiency. Mixture of BMPOTF and MSA based tin plating solution gave current efficiency as …

Synthesis And Characterization Of Limpo[4] (M=Mn, Ni And Fe) Olivine Materials., Azlin Sanusi

Student Works (2010-2019)

Lithium transition metal phosphate, LiMPO4 compounds with olivine structure namely LiMnPO4, LiNiPO4 and LiFePO4 were successfully synthesized in the present work. LiMnPO4 and LiNiPO4 were synthesized by the sol-gel method with tartaric acid as the chelating agent. LiFePO4 was synthesized via the chemical precipitation and low temperature sterilizer heating method. TGA was carried out on LiMnPO4 and LiNiPO4 samples to determine the firing temperature of the gel precursor and the thermal stability of the prepared samples. LiMnPO4 was heated for 15 hours at various temperatures and LiNiPO4 was formed at 1000 oC with firing time of 24 hours. Firing of …

Inductively Coupled Plasma Dry Etching Process On Planar Lightwave Circuit Fabrication., Chuah Khoon Seah

Student Works (2010-2019)

The main objective of this project is to master state-of-the-art techniques and knowledge in silica etching in order to achieve high quality waveguide circuit on Planar Lightwave Circuit devices. Another objective is to optimize the clean room research strength, surface characterization, microscopy techniques and similar semiconductor manufacturing processes.Initially, these processes were conducted with wet etching method that utilized diluted hydrofluoric acid (HF) and buffered oxide etch (BOE). Several problems arising such as mask peel-off, poor sidewall profile and defect waveguide channel during the pattern transfer process due to its’ isotropic nature. Alternatively, dry etching method was conducted via Inductively Coupled …

Strain-Stiffening In Synthetic And Biopolymer Networks, Kendra Erk, Kevin J. Henderson, Kenneth R. Shull

School of Materials Engineering Faculty Publications

Strain-stiffening behavior common to biopolymer networks is difficult to reproduce in synthetic networks. Physically associating synthetic polymer networks can be an exception to this rule and can demonstrate strain-stiffening behavior at relatively low values of strain. Here, the stiffening behavior of model elastic networks of physically associating triblock copolymers is characterized by shear rheometry. Experiments demonstrate a clear correlation between network structure and strain-stiffening behavior. Stiffening is accurately captured by a constitutive model with a single fitting parameter related to the midblock length. The same model is also effective for describing the stiffening of actin, collagen, and other biopolymer networks. …

Electrochemical Characterization Of Cerium-Based Conversion Coatings On Al 7075-T6, Simon Joshi

Doctoral Dissertations

"This research used electrochemical techniques to characterize the deposition and corrosion protection behavior of cerium-based conversion coatings on AI 7075-T6. Alkaline activation decreased native oxide impedance (5.9 kΩ-cm²) by ~25% promoting deposition of 250-500 mn coatings. Activation in NaOH solutions deposited coatings with large cracks and craters, whereas Na₂C0₃ activation resulted in uniform coatings, i.e., fewer cracks and almost no craters. Uniformly deposited coatings exhibited better cathodic inhibition and higher impedance (~200 kΩ-cm²) than on NaOH activated substrates (~100 kΩ-cm²). Subsurface crevices, caused by Cl⁻ and H₂O₂ in the deposition solution, were found under large cracks and craters. Thus, Na₂CO₃ …

Fluid Flow Related Phenomena And Inclusion Motion In Continuous Casting Strands, Yufeng Wang

Doctoral Dissertations

"To improve the efficiency of the continuous casting process and the quality of its products, this dissertation mainly investigated fluid flow related phenomena and inclusion motion in continuous casting. Mathematical simulation was performed for this purpose. Both a slab caster and a billet caster were investigated. In the study of the slab caster, the application of electromagnetic brake field on the slab mold was evaluated. The results indicated that the magnetic force decelerated the high speed steel jet, stabilized the top fluctuation, and prevented the bias flow inside the mold. The other study of this slab caster involved the fluid …

Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, Lihua Qian, Biswajit Das, Yan Li, Zhilin Yang

Electrical & Computer Engineering Faculty Research

Hot spots have the contradictively geometrical requirements for both the narrowest interstices to provide strong near-field coupling, and sufficient space to allow entrance of the analytes. Herein, a two-step method is employed to create hot spots within hybrid nanostructures, which consist of self-supported nanoporous gold films with the absorbed probes and subsequent nanoparticle conjugates without surface agents or mechanical motion. The molecules confined into 1 nm interstice exhibit 2.9 × 10⁷ times enhancement in Raman scattering compared to pure nanoporous gold. Giant enhancement primarily results from strong near-field coupling between nanopore and nanoparticle, which is theoretically confirmed by finite-difference …

Mse News 2010, Department Of Materials Science And Engineering, Michigan Technological University

Department of Materials Science and Engineering Annual Reports

Table of Contents

• MSE Welcomes New Professors
• Professor Emeritus Passes
• Alumni Achieves Milestone
• Hydrogen Storage Research
• Student Accomplishments
• Staff News
• Alumni News

Production And Characterization Of Novel Air Filtration Media, Elizabeth Skomra

All Dissertations

HEPA and ULPA filtration systems have proven to be an advantageous instrument in removing common contaminants from the air. However, an increased pressure drop due to the build-up of particulates on the filters results in its inevitable decrease in performance. Improving current filtration systems would include increasing collection efficiency all the while either maintaining or reducing the differential pressure drop in order to extend the life of the filter. One method of improving collection efficiency would be viable by increasing the amount of surface area within the filter media by glass fibers because of their inherent quality of being smaller …

Excitation-Induced Germanium Quantum Dot Formation On Si (100)-(2×1), Ali Oguz Er, Hani E. Elsayed-Ali

Physics Faculty Publications

The effect of nanosecond pulsed laser excitation on the self-assembly of Ge quantum dots grown by pulsed laser deposition on Si (100)-(2×1) was studied. In situ reflection high-energy electron diffraction and ex situ atomic force microscopy were used to probe the quantum dot structure and morphology. At room temperature, applying the excitation laser decreased the surface roughness of the grown Ge film. With surface electronic excitation, crystalline Ge quantum dots were formed at 250 °C, a temperature too low for their formation without excitation. At a substrate temperature of 390 °C, electronic excitation during growth was found to improve the …

Experimental Study On Thermal Treatment Of Used Printed Wiring Boards (Pwbs), Xiangjun Zuo

Masters Theses

The availability of cheaper and better electronic products as a result of the rapid innovation in technology in past decades has driven the production of e-waste forward. Printed wiring board (PWB) is a component made of one or more layers of insulating material with electrical conductors. The existing processes of recycling PWBs use pyrometallurgical or hydrometallurgical methods, which generate atmospheric pollution. Green recycling has obvious benefits to decrease the amount of PWBs. Green recycling includes two features, 1) little or zero pollution of toxic gases and heavy metals, and 2) efficient (quick and economical) recycling.

The aim of this work …

Zinc Iron Phosphate Glasses For Enameling Applications, Sagnik Saha

Masters Theses

"New compositions of low temperature black glasses were developed that are suitable as frits for enameling soda-lime silicate (S-L-S) glass substrates. Zinc iron phosphate glasses are of interest for this application because they possess dilatometric low softening points (under 600ºC) and have coefficients of thermal expansion that are compatible with S-L-S glass (in the range 90-110x10⁻⁷/ºC). The development of compositions with excellent chemical durability, particularly in acidic conditions, is also desired. Compositional modification were made to the (Na₂O+K₂O)·ZnO·MnO·Fe₂O₃·P₂O₅ glass system using design of experiments. The compositional boundaries used in the design were based on earlier work at Missouri S&T. The …

Foundry Parameters For Casting High-Aluminum Lightweight Steel In Complex Shapes, Angella Marie Schulte

Masters Theses

"This work investigated the liquid metal treatment and molding practices for Fe- 30wt.%Mn-9wt.%Al-1wt.%Si-0.9wt.%C-0.5wt.%Mo steel. The goal of this research was to determine the process conditions that would produce a tough Fe-Mn-Al-C alloy and the appropriate mold design to produce a defect-free P900 plate.

Notch toughness of age-hardenable Fe-Mn-Al-C alloys decreases as phosphorus increases. Thermodynamic calculations and experimental work show that additions of Ca followed by Ce can be used to mitigate the deleterious effects of phosphorus, and the addition of Ar-stirring can be used to decrease the number of harmful aluminum nitride inclusions. In the solution-treated and aged condition (Brinell …

The Properties And Structure Of Tin Phosphate Glasses Modified With Other Oxides, Jong Wook (Austin) Lim

Masters Theses

"The main objective of this research was to evaluate the properties and structures of glasses from the stannous (SnO) phosphate system for possible use in low temperature optical applications. Glasses in the binary xSnO-(100-x)P₂O₅ system (50 ≤ x ≤ 70) were prepared and their thermal and optical properties were evaluated. Differences in glass transition temperatures (T_g) measured here and reported in the literature were explained by differences in the residual water content in the glasses, as determined by infrared spectroscopy. In general, increasing the SnO content of the binary glasses increased the refractive index and the glass transition …

Sensitivity Analysis Of The Johnson-Cook Plasticity Model For Hypervelocity Impacts: A Hydro-Code Study, Carlos David Castellanos

Open Access Theses & Dissertations

Computer simulations have been in use for decades in the modeling of hypervelocity impacts and general large deformation problems. Several computer codes have been developed to simulate this type of problems under a variety of geometric configurations and for any number of materials. These codes make use of several constitutive material models to simulate the response of the material under a variety of thermo-mechanical conditions. The Johnson-Cook constitutive model is widely used in the simulation hypervelocity impacts for the simulation of crater formation and even perforation of target structures. This thesis presents the results of a sensitivity study of this …

Selection Process, Modified Impact Testing And Failure Analysis Of An Electron-Beam-Melted Ti-6al-4v 3d Tessellation Based On The Eulerian Path Of The First Stellation Of The Rhombic Dodecahedron Open Unit Cell, Hugo Lopez

Open Access Theses & Dissertations

Ti-6Al-4V lattice block structures manufactured through the electron beam melting (EBM) process are a promising field in design and research due to great advantages that the alloy, the process and the final product offer. Three lattice block structures were manufactured through the electron beam process using an ARCAM A2 machine. The structures were designed using the MATERIALIZE^TM software and were designed around different types of unit cells. Compression testing was performed and one unit cell was selected due to its anisotropic behavior for modified impact testing. The same unit cell was used and it was scaled up to add …

Processing Of Zrb2-Zrc-Zrxsiy Ceramic By Reactive Metal Penetration, Nischel B. Maheswaraiah

Open Access Theses & Dissertations

The processing of ZrB2-ZrC-ZrxSiy composite by reactive metal penetration was investigated as a successor to the ZrB2-SiC composites for hypersonic vehicles application, which cannot be used for extended time at temperatures greater than 1600C due to formation of SiO and CO gases. Zirconium (Zr), zirconium disilicide (ZrSi2), and boron carbide (B4C) were reacted in graphite crucibles for 60, 120, 180, and 240 minutes. Microscopy and x-ray diffraction (XRD) deduced the formation of a heterogeneous microstructure of ZrB2-ZrC-ZrxSiy precipitates surrounded by a solidified Zr-Si melt. Unreacted boron carbide was observed in samples held at 1860C for 60 minutes and 120 minutes, …

Effect Of Cu Addition On The Conductivity Of Xcui-(1-X)Agi,(0.1 _ X _ 0.4) Solid Solutions., Chu Lee Peng

Student Works (2010-2019)

Silver Iodide (AgI) based superionic conductors continue to be investigated for their intriguing structure phase transformation and complex but useful ion dynamics. However, unlike the others alkali iodides, AgI does not easily admit impurities in its tetrabonded zincblende structure. Introduction of copper (I) iodide (CuI) into AgI lattice was expected to initiate and stabilize changes in structure of the cation sublattice which controls the phase stability and phase transition behavior. In the present work, silver rich xCuI-(1-x)AgI (0.1 ' x ' 0.4) have been prepared by sintering method. The mixtures were ground and pelletized before subjected to sintering temperature at …

Phosphate Post-Treatment Of Cerium-Based Conversion Coatings On Al 2024-T3, Daimon K. Heller

Doctoral Dissertations

"Phosphate post-treatment of cerium-based conversion coatings (CeCCs) on high strength aluminum alloys can significantly improve corrosion resistance. As-deposited CeCCs exhibit corrosion pits and salt tails across the specimen surface after 3 days of exposure, but post-treated CeCCs have withstood 14 days of salt spray exposure without visibly corroding. The morphology, phase, and electrochemical properties of spray deposited CeCCs were affected by post-treatment parameters such as immersion time, solution temperature, and phosphate source. The best performing coatings were post-treated in aqueous orthophosphate solutions for at least 5 min at temperatures of at least 85⁰C. These conditions converted cerium hydroxy/peroxy species in …

Resistance Switching In Electrodeposited Magnetite Thin Films, Samantha Glen Matthews

Masters Theses

"The resistance switching phenomenon has been extensively studied in metal oxide thin films for its applications in the non-volatile memory industry. The research presented here focuses on magnetite thin films which have been electrodeposited onto gold-sputtered glass substrates via the electrochemical reduction of a Fe(III)-triethanolamine complex in aqueous alkaline solution. Magnetite was chosen for its usefulness in read/write memory applications, its high Curie temperature, its metal-to-insulator (Verwey) transition, and its half-metallic character and attendant spintronic properties. Resistance switching behavior caused by a reversible redox reaction at the anode was observed in the films, demonstrating that electrodeposited films show the same …