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Displaying 76 - 100 of 1316

The Nanostructure Problem

October 12, 2021
Author(s)
Simon J. Billinge, Igor Levin
The powerful methods we have for solving the atomic structure of bulk crystals fail for nanostructured materials and there are currently no broadly applicable, quantitative and robust methods to replace them. The solution of this nanostructure problem is

Theory of Strain Percolation in Metals

October 12, 2021
Author(s)
R Thomson, Lyle E. Levine
We demonstrate that a deforming metal is a self organizing critical system, and that the stress-strain law can be expressed as an integration of certain derivatives of internal variables along the critical line of the system.

Towards Optimization of Patterned Superhydrophobic Surfaces

October 12, 2021
Author(s)
Bharat Bhushan, Michael Nosonovsky, Yong C. Jung
Experimental and theoretical study of wetting properties of patterned Si surfaces with cylindrical flat-top pillars of various sizes and pitch distances is presented. The values of the contact angle (CA), contact angle hysteresis (CAH) and tilt angle (TA)

Tribological Performance of Head-Disk Interface Due to Nanoasperity Impacts

October 12, 2021
Author(s)
Tze J. Chuang, Stephen M. Hsu
During the track accessing mode ofa hard disk drive, theflying height of the slider over thedisk surface becomes smaller and smaller as the demand in data storage density increases. As aresult, the propensity of glide avalanche is bound to increase when

Understanding Deviations in Lithographic Patterns Near Interfaces: Characterization of Antireflective Coatings (ARC) and the ARC/Resist Interface

October 12, 2021
Author(s)
Joseph~undefined~undefined~undefined~undefined~undefined Lenhart, Daniel A. Fischer, S Sambasivan, Eric K. Lin, Wen-Li Wu, Douglas Guerrero, Yijun Wang, R Puligadda
Interactions between a bottom anti-reflective coating (BARC) and a photo-resist can critically impact lithographic patterns. For example, a lithographic pattern can shrink or spread near a BARC interface, a process called undercutting or footing

Viscous Flow Creep in Ceramics Containing Secondary Crystalline Phases

October 12, 2021
Author(s)
Q Jin, D S. Wilkinson, G C. Weatherly, William E. Luecke, Sheldon M. Wiederhorn
Experimental observations of the creep response of a Y 20 3-fluxed Si 3N 4 containing secondary crystalline phases(SP)are presented.The widths of grain-boundary amorphous films before and after creep have been characterized by using transmission electron

Volumetric and Size Characterization of Void Morphologies in Thermally Sprayed Metallic Deposits Using Scattering Techniques

October 12, 2021
Author(s)
T Keller, W. Wagner, J Ilavsky, Andrew J. Allen, N Margadant, S Siegmann, J Pisacka, G Barbezat, R Enzl
The complex void microstructure of thermally sprayed deposits may be approximated by three major void syste(interlamellar pores, intralamellar cracks, and volumetric globular voids), each with different volume fractions,anisotropies, sizes and shapes. This

Wear Analysis of UHMWPE Using a Load Sum Method

October 12, 2021
Author(s)
M C. Shen, Stephen M. Hsu, John A. Tesk, A Christou
An accelerated wear test pro-cedure has been developed for wear screening of ultra-high molecular weight polyethylene (UHMWPE) using a new wear tester. Results showed that the test procedure was able to discriminate known wear level samples within seven

Rapid Identification of Synthetic Routes to Functional Metastable Phases Using X-Ray Probed Laser Anneal Mapping (XPLAM) Time-Temperature Quench Maps

June 6, 2021
Author(s)
Robert T. Bell, Peter A. Beaucage, Marc J. Murphy, Aine Connolly, David Ginley, Ulrich Wiesner, R. B. Van Dover, Michael O. Thompson
Most material systems have known or predicted functional phases that are metastable at standard temperature and pressure. While substantial advances have been made in the high-throughput and combinatorial synthesis of materials with a range of

Exploring the First High Entropy Thin Film Libraries: Composition spread-controlled Crystalline Structure

March 19, 2021
Author(s)
Thi X. Nguyen, Yen-Hsun Su, Jason Hattrick-Simpers, Takahiro Nagata, Howard Joress, Kao-Shuo Chang, Suchismita Sarker, Apurva Mehta, Jyh-Ming Ting
Thin films of two types of high-entropy oxides (HEOs) have been deposited on 76.2 mm Si wafers using combinatorial sputter deposition. In one type of the oxides, (MgZnMnCoNi)Ox, all the metals have a stable divalent oxidation state and similar cationic

Effects of Octahedral Tilting on the Site of Substitution of Manganese in CaTiO3

January 22, 2021
Author(s)
Russell Maier, Kevin Garrity, Matthew P. Donohue, Andrzej Ozarowski, Igor Levin
Combined electron-paramagnetic-resonance and X-ray absorption spectroscopies with first principles calculations were used to investigate the substitutional behavior of Mn ions in perovskite CaTiO3 ceramics. While transition-metal dopants in perovskite

In situ characterization of ceramic cold sintering by small-angle scattering

January 1, 2021
Author(s)
Andrew J. Allen, Igor Levin, Russell Maier, Suzanne E. Witt, Fan Zhang, Ivan Kuzmenko
The first in situ characterization of the pore morphology evolution during the cold sintering process (CSP) is presented using small-angle X-ray scattering methods. For practical reasons, measurements have been made on a model system, KH2PO4 (KDP). The

Shoulder fillet effects in strength distributions of MEMS components

November 6, 2020
Author(s)
Frank W. DelRio, Brad L. Boyce, Jake T. Benzing, Lawrence H. Friedman, Robert F. Cook
The failure forces and fracture strengths of polysilicon MEMS components in the form of stepped tensile bars with shoulder fillets were measured using a sequential failure chain methodology. Approximately 150 specimens for each of four fillet geometries

Materials Research & Measurement Needs for Ceramics Additive Manufacturing

November 1, 2020
Author(s)
Andrew J. Allen, Igor Levin, Suzanne E. Witt
We report on a recent workshop dedicated to additive manufacturing (AM) of ceramics that was held at the National Institute of Standards and Technology (NIST) in November 2019. This two- day all-invited meeting brought together experts from industry

Local negative permittivity and topological-phase transition in polar skyrmions

October 12, 2020
Author(s)
Sujit Das, Zijian Hong, Vladimir Stoica, Mauro A. Goncalves, Yu-Tsun Shao, Eric Parsonnet, Eric J. Marksz, Sahar Saremi, Margaret McCarter, A Reynoso, Chris Long, Aaron Hagerstrom, D Meyers, V Ravi, B Prasad, H Zhou, Z Zhang, H Wen, F Gomez-Ortiz, P Garcia-Fernandez, J Bokor, J Iniguez, J Freeland, Nate Orloff, J Junquera, Long-Qing Chen, Sayeef Salahuddin, David A. Muller, L Martin, R. Ramesh
Topological solitons such as magnetic skyrmions have drawn enormous attention as stable quasi- particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric- oxide superlattices, exhibiting exotic physical phenomena, has
Displaying 76 - 100 of 1316