Materials Science and Engineering Commons^™

Workforce Development Symposiums For Uhpc, Brad Weldon, Craig Newtson, Grace Mcmurry, Leticia Davila

Publications

Ultra-high performance concrete (UHPC) is a cementitious material with a dense microstructure that contributes to high compressive strengths as well as enhanced durability properties. UHPC also possesses significant post-cracking strength and ductility due to the addition of fibers. These characteristics produce a material that provides advantages over conventional concrete; however, high costs attributed to materials and production, lack of industry familiarity and knowledge, and the absence of standardized design procedures have impeded its widespread use. To help disseminate knowledge on UHPC, two workforce development symposiums on UHPC were held in Las Cruces, New Mexico. The symposiums consisted of presentations and …

Use Of Bagasse Ash As A Concrete Additive For Road Pavement Application, Gabriel Arce, Marwa Hassan, Maria Gutierrez, Michele Barbato

Publications

The objective of this study was to evaluate the use of sugarcane bagasse ash (SCBA) as a partial replacement of cement in concrete for road pavement application. The study explored the pozzolanic activity of SCBA produced from three different processing methodologies (i.e., raw SCBA, controlled SCBA and post-processed SCBA). The experimental results revealed that SCBA produced by the controlled burning of sugarcane bagasse fiber (SBF) at 650°C and grinding (C-650), presented the maximum pozzolanic activity. However, this SCBA production process was deemed challenging for large-scale industrial application due to low SCBA yield (i.e., 3 to 6%). On the other hand, …

Disaster Resilient And Self-Assessing Multifunctional Transportation Structures, Ibrahim Karaman, Darren Hartl

Publications

This research designs and characterizes multifunctional materials, in particular inexpensive shape memory alloys, for transportation structures that possess excellent mechanical properties and self-sensing capabilities for strengthening and health monitoring. The properties are the Fe-SMAs are sensitive to part size in that the grain size of the material, which can be grown to several inches, should exceed the smallest dimension of the part. In the current work, maximum part size of the large dimension Fe-SMA rods were determined through detailed microstructural investigations. Samples were subjected to abnormal grain growth heat treatments and found out that part size be increased up to …

Structure And Properties Of Zno-Zns Heterostructures, Sanchali Das

Graduate Theses/Dissertations

Heterostructures consisting of at least two layers of dissimilar materials have always been well studied due to potential applications in nano-electronic and optoelectronic devices. In this study, I have investigated the structural and physical properties of zinc oxide -zinc sulfide (ZnO-ZnS) based heterostructures of thin films and core-shell nanoparticles. Pulsed laser deposition technique was employed to grow ZnO thin film on sapphire substrate. ZnO-ZnS heterostructures were obtained using hydrothermal synthesis where thiourea has served as a precursor solution for the source of sulfur. X-ray diffraction analysis on the parent and the sulfidized samples gives the information about the crystallinity and …

Infrared Glass–Ceramics With Multidispersion And Gradient Refractive Index Attributes, Laura Sisken, Myungkoo Kang, Johann M. Veras, Charmayne Lonergan, Andrew Buff, Anupama Yadav, Devon Mcclane, Cesar Blanco, Clara Rivero-Baleine, Theresa S. Mayer, Kathleen A. Richardson

Materials Science and Engineering Faculty Research & Creative Works

Infrared (IR) glass–ceramics (GCs) hold the potential to dramatically expand the range of optical material solutions available for use in bulk and planar optical systems in the IR. Current material solutions are limited to single- or polycrystalline materials and traditional IR-transparent optical glasses. GCs that can be processed with spatial control and extent of induced crystallization present the opportunity to realize an effective refractive index variation, enabling arbitrary gradient refractive index elements with tailored optical function. This work discusses the role of the parent glass composition and morphology on nanocrystal phase formation in a multicomponent chalcogenide glass. Through a two-step …

A Displacement Controlled Fatigue Test Method For Additively Manufactured Materials, Mohammad Masud Parvez, Yitao Chen, Sreekar Karnati, Connor Coward, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

A novel adaptive displacement-controlled test setup was developed for fatigue testing on mini specimens. In property characterization of additive manufacturing materials, mini specimens are preferred due to the specimen preparation, and manufacturing cost but mini specimens demonstrate higher fatigue strength than standard specimens due to the lower probability of material defects resulting in fatigue. In this study, a dual gauge section Krouse type mini specimen was designed to conduct fatigue tests on additively manufactured materials. The large surface area of the specimen with a constant stress distribution and increased control volume as the gauge section may capture all different types …

Triple-Junction Solar Cells : In Parallel., Levi C Mays

Electronic Theses and Dissertations

This paper looks into the current inefficiency of solar cells and attempts a few alternative solar cell structures in order to provide a more effective source of renewable energy. Currently, multi-junction solar cells are being developed to capture the sun’s light more efficiently. One of the ideas in this paper is to add a window to see if the addition of such a layer into a junction will increase the voltage while maintaining nearly the same current output. Central to this paper is the rearranging of the conducting layers of the multi-junction cell so that the junctions can be connected …

A Study Of Protein And Peptide-Directed Nanoparticle Synthesis For Catalytic Materials, Abdollah Mosleh

Graduate Theses and Dissertations

Nanoparticles have received much attentions due to their unique properties that makes them suitable candidates for a broad range of applications. As the size of particles decreases, their surface area-to-volume ratio would increase which is the main cause of much attention. In addition to the size, their morphologies and compositions may also play important roles for defining unique properties. Nanoparticle synthesis include both bottom-up and top-down strategies. To control the process of inorganic nanoparticles synthesis one could follow the bottom-up approach to have atom-level control over their compositions, morphologies, phases, and sizes which is the subject of this work. Due …

Switching Trajectory Control For High Voltage Silicon Carbide Power Devices With Novel Active Gate Drivers, Shuang Zhao

Graduate Theses and Dissertations

The penetration of silicon carbide (SiC) semiconductor devices is increasing in the power industry due to their lower parasitics, higher blocking voltage, and higher thermal conductivity over their silicon (Si) counterparts. Applications of high voltage SiC power devices, generally 10 kV or higher, can significantly reduce the amount of the cascaded levels of converters in the distributed system, simplify the system by reducing the number of the semiconductor devices, and increase the system reliability.

However, the gate drivers for high voltage SiC devices are not available on the market. Also, the characteristics of the third generation 10 kV SiC MOSFETs …

Growth Of Indium Nitride Quantum Dots By Molecular Beam Epitaxy, Steven P. Minor

Graduate Theses and Dissertations

Over the last decade, the evolution of the global consciousness in response to decreasing environmental conditions from global warming and pollution has led to an outcry for finding new alternative/clean methods for harvesting energy and determining ways to minimize energy consumption. III-nitride materials are of interest for optoelectronic and electronic device applications such as high efficiency solar cells, solid state lighting (LEDs), and blue laser (Blu-ray Technology) applications. The wide range of direct band gaps covered by its alloys (0.7eV-6.2eV) best illustrates the versatility of III-nitride materials. This wide range has enabled applications extending from the ultraviolet to the near …

Preparation Of Chitosan-Polyethylene Oxide-Colocasia Esculenta Flour Nanofibers Using Electrospinning Method, Riesca Ayu Kusuma Wardhani, Lia Asri, Muhamad Nasir, Bambang Sunendar Purwasasmita

Journal of Mechanical Engineering Science and Technology (JMEST)

Nanofibers have been prepared from the mixture of chitosan, polyethylene oxide (PEO) and Colocasia esculenta flour (CE flour) by using the electrospinning method. Two different nanofibers were formulated, containing chitosan-PEO and chitosan-PEO-CE flour. The higher concentration of PEO (3%chitosan-6%PEO) (w/v) resulted in more uniform chitosan-PEO electrospun nanofibers without beads. Chitosan-PEO-CE flour was prepared by addition of colloidal CE flour into the solution containing 3%chitosan-6%PEO with variation of the CE flour concentration of 5, 15 and 25% (w/v). Scanning Electron Microscopy demonstrated that the average diameter of chitosan-PEO nanofibers was 128±41 nm, whereas the diameter of chitosan-PEO-CE flour nanofibers was 159±45 …

The Effect Of Chemical Pretreatment Process On Mechanical Properties And Porosity Of Bacterial Cellulose Film, Tito Arif Sutrisno, Heru Suryanto, Retno Wulandari, M. Muhajir, Shikh Mohd Shahrul Nizan Shikh Zahari

Journal of Mechanical Engineering Science and Technology (JMEST)

Bacterial cellulose (BC) is a natural polymer which have superior properties, like high porosity, high purity, and high permeability. The study objective is to determine the influence of chemical pretreatment on tensile strength and the porosity of BC. The method was to make BC films from pineapple peel extract through fermentation process for 14 days. The pretreatment was conducted by immersion of BC in BmimCl, H2O2, and NaOH solution with a concentration of 2.5%; 5%; and 7.5 %, heated at 80 °C then dried in the oven, and the samples were then tested by a tensile test using ASTM-D636-V standard, …

Elastic Linear Analysis Of Connecting Rods For Single Cylinder Four Stroke Petrol Engines Using Finite Element Method, Didin Zakariya Lubis, Andoko Andoko

Journal of Mechanical Engineering Science and Technology (JMEST)

A connecting rod is one of the most critical parts in engine assembly which transfers energy from the piston to the crankshaft. The connecting rod mainly undergoes tensile and compressive loading under engine cyclic process. The forces acting on the connecting rod are forces due to maximum combustion pressure and forces due to the inertia of the connecting rod. This research aimed to analyze the design of the connecting rod of single-cylinder four-stroke engines. This study used CAD software for modeling and structural design. Stresses generated across all the locations of the connecting rod were evaluated using FEA Software. Elastic …

The Characteristic Of Overhang Object To Material Usage On Fdm 3d Printing Technology, Redyarsa Dharma Bintara, Aminnudin Aminnudin, Zumrotul Ida, Ferian Rizki Arbianto, Dani Prasetiyo

Journal of Mechanical Engineering Science and Technology (JMEST)

Fuse Deposition Modeling (FDM) 3D printing is one of additive manufacturing technology which physical 3D model is build up layer by layer. The support structure is almost involved on the process if overhang shape is met on the 3D model. It has main function to prevent the 3D printed model from collapsing. Commonly, the single material source of FDM 3D printer machine is to supply building two structure, structure of main 3D object and support structure. Hence, our goal optimizes the using of support material for reducing the main material usage. Furthermore, the sixteen of variation overhang angle is set …

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. …

Study On The Thermal Distortion, Hardness, And Microstructure Of St 37 Steel Plate Joined Using Fcaw, Maijuansyah Maijuansyah, Yanuar Rohmat Aji Pradana, Gaguk Jatisukamto, Solichin Solichin

Journal of Mechanical Engineering Science and Technology (JMEST)

This study sets out to investigate the distortion angle, microstructure, and hardness of St 37 steel plate weld joint produced by FCAW using the welding current of 80, 110, and 140 A. By using flat position, CO2 and E71T-1 wire were utilized as a shielding gas and electrode filler, respectively. The distortion angle measurement was done on 3 different locations of the welded sample perpendicular to weld direction by using bevel protractor. The micro Vickers tests were then applied gradually at the crosssectional surface with a distance of 0, 5, 10 and 15 mm from weld centerline using the load …

Comparison Study Of Mechanical Properties Of Al-Si Alloy With And Without Nanoreinforce Iron Oxide (Fe2o3), Cepi Yazirin, Poppy Puspitasari, Muhamad Fatikul Arif

Journal of Mechanical Engineering Science and Technology (JMEST)

Nanoreinforce materials such as ZnO, eggshell, Al2O3, TiO2, and ZrO2 have been shown to improve the mechanical properties of Al-Si alloy. Nanomaterial Fe2O3 has many applications as catalysts reaction in electronic devices, for example, semiconductor materials, paint formulations, lithium rechargeable batteries, and is often applied in industrial fields. It is known that Fe2O3 can be synthesized through the stirring process on machine and method used will involve several steps that relatively take a long time. In this study, Al-Si alloy reinforced by using nanomaterial Fe2O3 which sintered at a temperature of 600C for 3 hours aimed to improve mechanical and …

The Influence Of Different Packaging Materials And Atmospheric Conditions On The Properties Of Pork Rinds, Kristi Kõrge, Katrin Laos

Journal of Applied Packaging Research

Rancidity development in high fat content products is a common off-flavor flaw in snack foods. Packaging is often used to avoid spoilage and extend shelf-life. The properties of pork rinds packaged in four different packaging materials with and without nitrogen were studied during 120 days of storage (22 °C, RH 60%, absence of light). The influence of different packaging materials and atmospheric conditions on pork rinds’ water activity, hardness, crispness and rancidity development was determined. The PET/PE packaging material had lower barrier properties for the product in both atmospheric conditions compared with PP/metPP (40 and 50 μm) and PET/PETmet/PE. PP/metPP …

Nanoporous Gold And Other Related Materials, Keith Stine

Chemistry & Biochemistry Faculty Works

No abstract provided.

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.