A5083817846- Magnetic Properties and Applications
- Microstructure and Mechanical Properties of Steels
- Magnetic properties of thin films
- Non-Destructive Testing Techniques
- Metallic Glasses and Amorphous Alloys
- Magnetic Properties of Alloys
- Electric Motor Design and Analysis
- Ultrasonics and Acoustic Wave Propagation
- Shape Memory Alloy Transformations
- Metallurgy and Material Forming
- Magneto-Optical Properties and Applications
- Hydrology and Sediment Transport Processes
- Acoustic Wave Resonator Technologies
- High Entropy Alloys Studies
- High-Temperature Coating Behaviors
- Anodic Oxide Films and Nanostructures
- Copper Interconnects and Reliability
- Structural Health Monitoring Techniques
- Semiconductor materials and devices
- Electrodeposition and Electroless Coatings
- Multiferroics and related materials
- Innovative Energy Harvesting Technologies
- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Vibration Control and Rheological Fluids
Naval Surface Warfare Center
2019-2022
University of Maryland, College Park
2010-2019
Park University
2018
Sungkyunkwan University
2002-2007
Korea Institute of Science and Technology
2004
A MME generator with a textured Fe–Ga alloy can generate over 1 mW power under tiny magnetic field.
Abstract Arrays of nanowires are fabricated with alternating segments the magnetostrictive alloy Fe 1– x Ga and Cu using electrochemical deposition in nanoporous anodic aluminium oxide (AAO) templates. The difficult nature Ga‐alloy electrochemistry is overcome by controlling mass‐transfer hydrodynamic conditions novel rotating disk electrode templates to obtain highly uniform segment lengths throughout arrays. Extensive structural characterization XRD, EBSD TEM reveals a strong <110>...
Single crystal samples of quenched Fe81.3Ga18.7 and slow cooled Fe81.3Ga18.6C0.08 exhibit magnetostriction ∼400ppm. However, they also a sufficiently high permeability that eddy currents, which form in proportion to sample thickness, limit their operation at frequencies. During attempts roll thin sheets carbon-added Fe81Ga19 alloys, cracks formed along grain boundaries subsequently fractured during hot rolling such the alloy was too brittle make sheets. In this paper, influence alloying...
High-entropy alloys (HEAs) containing multiple principle alloying elements exhibit unique properties so they are currently receiving great attention for developing innovative alloy designs. In FeCoNi-based HEAs, magnetic behaviors strongly depend on the addition of elements, usually accompanied by structural changes. this work, effect non-magnetic components ferromagnetic transition and in equiatomic FeCoNiCrX (X=Al, Ga, Mn Sn) HEAs was investigated. Alloy ingots nominal compositions were...
The influence of high temperature annealing processes on abnormal grain growth in Galfenol (Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">81</sub> Ga xmlns:xlink="http://www.w3.org/1999/xlink">19</sub> alloy plus 1 mol% NbC) sheet is examined this paper. Results are presented magnetostriction and orientation after rolling processes. Abnormal (110) grains grew to several millimeters at 1200degC. changed from a gamma -fiber texture...
This paper presents the investigation of a directional magnetostrictive patch transducer (MPT) composed highly textured Galfenol (Fe–Ga alloy) in use ultrasonic guided Lamb wave (GLW) inspection techniques for isotropic planar structures. Recently, actuation and sensing performance an MPT using disc made polycrystalline nickel was reported, based on GLW testing thin aluminum plates. The nickel-based appeared to have omnidirectional sensitivity metallic plate because nature with random...
Single Goss grains were globally grown in magnetostrictive Galfenol thin sheets via an abnormal grain growth (AGG) process. The sample behaves like single crystal Galfenol, exhibiting large magnetostriction along the 〈100〉 axes. Small variations surface energy conditions, which governed by different flow rates of 0.5% H2S gas argon during annealing, had a significant impact development AGG. AGG with fully developed (011) over 95% is very reproducible and feasible for broad range annealing...
In this work, we investigate the effects of substituting Ni/Al for Cr on thermomagnetic and magnetocaloric properties FeCoNiCrAl-type high entropy alloys (HEAs). Ni Al appear to prefer BCC phase, increases in composition stabilize phase. contrast Al, content yields an increase FCC phase fraction, resulting a drop off magnetization. The transformation from was intensified at annealing temperatures 800 °C higher due increased diffusion rates spinodal decomposition. A magnetic transition around...
High entropy alloys (HEA) contain multiple principal alloying elements, and possess unique properties due to the high configurational lattice strain in system. Ferromagnetic FeCoNi-based HEAs exhibit dramatic changes crystal structure type of magnetism expressed when adding non-magnetic elements such as Al, Cr, Ga, Ti, etc. Interestingly, Alnico permanent magnets also Fe, Co, Ni, along with other minor additions. This well-studied system is similar concept (HEAs). In this paper, we...
An investigation into the relationship between measured bulk magnetostriction in rolled galfenol alloy sheet and texture components was conducted. Galfenol prepared using different annealing parameters such as temperature (1000–1300 °C), cooling rate, dwell time (1–24 h), with their saturation magnetostrictions measured, followed by electron backscattered diffraction to determine degree of that each sample possessed. The dominate orientation all samples analyzed {011}⟨100⟩, along desired...
Surface-energy-induced selective grain growth has been used to increase the presence of preferred planes in polycrystalline ternary Fe–Ga based alloys and thereby maximize magnetostrictive performance these alloys. In this study, were either doped with elemental sulfur or annealed under atmospheres control concentration on surface samples during annealing. We show that segregation sulfur, which is known play an important role controlling energy, can be correlated {001} grains saturation...
The surface-energy-induced secondary recrystallization growth with a specific surface plane can be governed in polycrystalline Fe–Ga alloy doped sulfur by controlling the segregation of through conventional rolling and texture annealing. Results that demonstrate recrystallization, magnetostriction, selective development {100}⟨001⟩ and/or {110}⟨001⟩ preferred Fe81.3Ga18.7 plus B (0.5–1.0at.%) S (∼0.05at.%) alloys are presented this work. addition boron was used to improve ductility enhancing...
In this paper, we investigate grain growth behaviors in Fe-Al-NbC rolled sheets annealed under a sulfur atmosphere at temperatures of 1000–1300 °C for NbC additions 0.75%, 1.0%, and 1.5%. Fe80Al20 sheet plus 0.75% NbC, abnormal (AGG) occurred higher temperature than 1150 °C. Large single (011) grains that covered 74%–90% sample surface were fully grown 1200–1300 For these samples, the remaining 10%–26% was comprised small isolated island-like dispersed throughout Goss matrix. The...
In this paper, we investigate ultrasonic guided wave (GW) sensing performance of a magnetostrictive composite patch sensor (MCPS) in use structural health monitoring system for metallic plates. A the MCPS consisted powders and binding epoxy, where flake- granular-type Galfenol spherical nickel particles were considered to examine effect particle shape on capability directional sensitivity. flakes with surface parallel (200) crystallographic planes exhibit good field sensitivities magnetic...
In this paper, the role of misorientation angle and coincident site lattice (CSL) boundaries in promoting Goss-textured abnormal grain growth (AGG) polycrystalline (Fe81Ga19)+1.0 mol % NbC rolled sheet is investigated through electron backscattering diffraction (EBSD) patterns captured by orientation imaging microscopy. Data on magnetostrictive variation as a function annealing time under an argon atmosphere are presented along with area fraction grains, average size, boundary character...
In this paper, we investigate the influence of sheet thickness on abnormal grain growth and texture development in NbC-added Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">80</sub> Al xmlns:xlink="http://www.w3.org/1999/xlink">20</sub> alloys (Alfenol) that are being used as sensors. Being able to reduce sensor is found be an important for parameter avoiding work-hardening sensors deflect. The alloy rolled form sheets with a 0.2, 0.35, 0.5...