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Tribological properties are crucial to the reliability of microelectromechanical systems/nanoelectromechanical systems (MEMS/NEMS). In this study, adhesion and friction measurements are made at micro- and nanoscales on single-crystal silicon (commonly used
A Kulkarni, A N. Goland, H Herman, Andrew J. Allen, J Ilavsky, Gabrielle G. Long, C A. Johnson, J A. Ruud
This paper describes the results from multidisciplinary characterization/scattering techniques employed for the quantitative characterization of industrial thermal barrier coating (TBC) systems used in advanced gas turbines. While past requirements for
Winnie K. Wong-Ng, Lawrence P. Cook, J Suh, James A. Kaduk
By applying controlled atmosphere methods to minimize the presence of carbonate, and CO 2 and H 2O contamination, subsolidus phase equilibria of the BaO-Sm 2O 3-CuOx system at pO 2 = 100 Pa (0.1 % O 2 by volume) were successfully determined. Under
Brian R. Lawn, Antonia Pajares, Yu Zhang, Y N. Deng, M Polack, Isabel K. Lloyd, E D. Rekow, Victoria Thompson
Results from a systematic study of damage in material structures representing the basic elements of dental crowns are reported. Tests are made on model flat-layer specimens fabricated from various dental ceramic combinations bonded to dentin-like polymer
Terrell A. Vanderah, V L. Miller, Igor Levin, S M. Bell, T Negas
Subsolidus phase equilibria, crystal chemistry, and dielectric behavior were studied for the La 2O 3 MgO TiO 2 system and for the ternary sections LaMg 1/2Ti 1/2O 3 CaTiO 3 La 2O 3 and LaMg 1/2Ti 1/2O 3 CaTiO 3 0.5La 2/3TiO 3 in the quaternary La 2O 3 CaO
Advanced ceramics are increasingly being used for wear applications. The strength and fatigue resistance of ceramics have increased several fold in the last decade. Wear prediction of ceramics has become an important subject in these arenas. Ceramic wear
D J. Burnett, A M. Gabelnick, A T. Capitano, Daniel A. Fischer, J L. Gland
In-situ oxidation experiments in oxygen pressures up to 1.3 Pa indicate that the 140 K carbon monoxide oxidation process is self-limiting. This experimental data suggests that adsorbed atomic oxygen may be responsible for limiting the extent of reaction
D J. Burnett, A M. Gabelnick, A L. Marsh, H D. Lewis, S M. Yalisove, Daniel A. Fischer, J L. Gland
rbon monoxide oxidation experiments were performed on a well-characterized supported platinum thin film using in-situ x-raytechniques and temperature-programmed reaction spectroscopy (TPRS) experiments over the 100 to 1000 K temperature range andhigh
We examine Gibbs' conditions for equilibrium of a non-hydrostatically stressed single component solid in equilibrium across one of its faces with a pure liquid at pressure p(superscriptF). We show that the equilibrium melting temperature T(subscriptN) for
D J. Burnett, A M. Gabelnick, A L. Marsh, Daniel A. Fischer, J L. Gland
Propyne and propylene oxidation have been studied on a 1 0 nm Pt/A 1 20 3 thin film catalyst using a combination of synchrotron basedsoft x-ray techniques for oxygen pressures up to 1.3 Pa. In-situ temperature-programmed and isothermal kinetic experiments
The strengths of fine microstructural scale yttria stabilized rectangular bars and circular disks were measured by four-point flexure and by flat ball (piston) on three ball methods. Fracture mirror sizes were measured and correlated to the strengths
Sheldon M. Wiederhorn, A R D Lopez, William E. Luecke, Michael J. Hoffmann, B Hockey, J French, D C. Yoon
The effect of grain size on the tensile creep of silicon nitride is investigated on two materials, one containing 5 % by volume Yb2O3, the other containing 5 % by volume Yb203 and 0.5 % by mass Al2O3. Annealing of the alumina-free silicon nitride increased
The propagation behavior (subcritical crack growth) of machining induced cracks in silicon nitride was investigated by conducting constant stress (CS) and constant stress rate (CSR) tests. A dye impregnation technique that forces a palladium nitrate
A Kulkarni, J Gutleber, S Sampath, A N. Goland, W B. Lindquist, H Herman, Andrew J. Allen, B A. Dowdy
High-velocity oxygen-fuel (HVOF) spraying stands out among the various processes to improve metal and ceramic coating density and surface characteristics. This paper explores microstructure development, coating characterization and properties of HVOF
The study of the interrelationships between processing, structure and properties of materials is fundamental to the field of materials science and engineering. The need to understand the microstructure of materials has driven the development of a wide
Three-dimensional Green's functions due to a point force and a point charge in multilayered anisotropic piezoelectric materials have been derived within the framework of generalized Stroh formalism and two-dimensional Fourier transforms. The material in
N G. Armstrong, W Kalceff, James Cline, John E. Bonevich
A single and self-contained method for determining the crystallite-size distribution and shape from experimental line profile data is presented. We have shown that the crystallite-size distribution can be determined without assuming a functional form for
The full potential of esthetic ceramic-based dental restorations has not yet been realized. Processing and surgical induced damage, exacerbated by fatigue damage during normal chewing, can reduce the initial strength of inherently brittle materials. The
A Kulkarni, H Herman, J Almer, U Lienert, D Haeffner
Demands for designing prime reliant, energy efficient and high performance thermal barrier coatings (TBCs) in gas turbines have led to growing interest towards comprehensive microstructural characterization. Here we investigate novel use of high-energy x