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S A. Prosandeev, Eric J. Cockayne, Benjamin P. Burton
K 1-xLi xTaO 3 (KLT) solid solutions exhibit a variety of interesting physical phenomena related to large local displacements of Li-ions from ideal perovskite A-site positions. First-principles calculations for KLT supercells were used to investigate these
Winnie K. Wong-Ng, L Swartzendruber, James A. Kaduk, Lawrence H. Bennett
The compounds BaR 2CuO 5 (R = Y, and lanthanides) are well known impurities that often coexist with the high T c superconductors, Ba 2RCu 3O 6+X. With R=La and Nd, brown color solid solutions (Ba 1+xR 2-xCuO 5-x) form instead of the green phase, BaR 2CuO 5
Epoxy resins are widely used as the matrix material for fiber reinforced composites in aircrafts, automobiles, ships and housing. Most of the reinforcement in epoxy composite is glass fiber so as to lower the cost. Studies in the past have suggested that
Data evaluation is the process by which collections of data are assessed with respect to reliability, completeness, and consistency. The present work addresses data evaluation for materials properties as a scientific discipline that evolves from the formal
We report on findings of the electrokinetic and solubility behavior of BCTZ powders having three different [Ba+Ca]/[Ti+Zr] ratios: 0.995, 1.000, and 1.005. Ba and Ca ions, occupying primarily A-sites on the perovskite lattice, dissolve during acid
Q Li, L Wu, Y Zhu, A R. Moodenbaugh, G Gu, M Suenaga, Z X. Ye, Daniel A. Fischer
We present our studies of superconducting and microstructural properties of bulk MgB 2/Mg nano-composites and press-sintered MgB 2. TEM investigation revealed that the composites are very dense, consisting of nano-sized MgB 2 grains connected by the well
J K. Park, D H. Kim, H Y. Lee, J Blendell, C A. Handwerker
Sapphire single crystals were imbedded in anorthite powders containing Cr 2O 3 and then heat-treated at 1600 degrees C. The resultant morphologies of sapphire-anorthite liquid interfaces were corrugated and quite different depending on the crystallographic
The fracture toughness of a commercial sintered reaction-bonded silicon nitride was measured by the three complementary test methods in ASTM C 1421. Precracks ranged from tiny artificial flaws introduced by Knoop indentation to millimeter long precracks in
In this paper, a brief review of the fiber-matrix interphase/interface region is given for carbon- and glass-fiber composites. The interphase/interface region is discussed interms of the fiber interphase (FI), the matrix (MI), and the FI-MI interface as
A new in-line process monitoring instrument, a dielectric slit die, was used to examine compounding of polymer/clay nanocomposites. It is a multi-purpose sensing device for measuring polymer dielectric, rheological and optical properties during extrusion
Machining cracks in ground sintered reaction-bonded silicon nitride (SRBSN) rods and bars were analyzed by fractographic techniques. Grinding flaw sizes were as small as 12 Jim and as large as 80 Jim and correlated strongly with grinding direction and
The size and severity of grinding machining cracks in a sintered reaction bonded silicon nitride from part I are compared to data for other silicon nitrides. Crack sizes follow a similar trend with grinding wheel grit size despite differences in
In this paper we discuss the application of pulsed laser deposition (PLD) to combinatorial materials research on inorganic thin films. The modifications to an existing PLD apparatus converting it to a dual beam dual target PLD system for the production of
The electronic structures of the ternary superconductors MoRuP and ZrRuP in the orthorhombic (o-) and hexagonal (h-) phases were calculated by a first-principles method and then compared. For h-MoRuP, the theoretically predicted structure was used. Based
A Kulkarni, Z G. Wang, T Nakamura, S Sampath, A N. Goland, H Herman, Andrew J. Allen, J Ilavsky, Gabrielle G. Long, J Frahm, R W. Steinbrech
Quantitative microstructure characterization to better understand processing-microstructure-property correlations is of considerable interest in plasma sprayed coating research. This paper quantifies, by means of small-angle neutron scattering (SANS) data
A Kulkarni, Z G. Wang, T Nakamura, S Sampath, A N. Goland, Gabrielle G. Long, H Herman, J. Allen, J Ilavsky, G J. Long, J Frahm, R W. Steinbrech
hieving control of the microstructure of plasma-sprayed thermal-barrier coating (TBC) systems offers an opportunity to tailor coating properties to demanding applications. Accomplishing this requires a fundamental understanding of the correlations between
The influence of poly (acrylic acid) PAA) and poly(vinyl alcohol) PVA) on Ba dissolution at the BaTiO 3-aqueous solution interface was investigated. Incongruent dissolution of Ba impacts the colloidal stability, microstructure and electrical properties of
Detailed ferromagnetic resonance measurements on the thin Ni{ 80}Fe{ 20} films are described that determine characteristics of intrinsic damping and the effects of intentionally created defects on linewidth. Measurements are made as a function of frequency
Lawrence H. Robins, B W. Steiner, Norman A. Sanford, C Menoni
Low electron energy cathodoluminescence (LEECL) was used to examine polishing-induced damage in a bulk high-pressure grown GaN single-crystal platelet. The Ga-polarity face of the platelet was mechanically polished; chemically-assisted ion-beam etching
The atomic force microscope is used to explore the nature of fracture surfaces in soda lime silicate glass formed near or below the apparent crack growth threshold. Conventional theory suggests that cracks in glass will blunt when subjected to stresses
Meticulous fractographic analysis of broken flexural strength specimens was used to characterize the size, shape, and severity of grinding flaws in a commercial silicon nitride. The cylindrical rods and rectangular bars were prepared by a varietyof
At high temperatures, polycrystalline materials often suffer creep fracture under prolonged loading conditions. Microstructural examinations revealthat nucleation, propagation and linkage of interfacial cracks normal to the principal stress directions are
T J. Haugan, Winnie K. Wong-Ng, Lawrence P. Cook, Mark D. Vaudin, L Swartzendruber, Paul N. Barnes
Partial-melt processing of Bi2+xSr2-x-yCa1+yCu2O8+d (Bi-2212) thick film conductors with additions of nanophase Al2O3 on Ag foils was studied for dual purposes of increasing flux pinning and inhibiting Sr-Ca-Cu-O defect formation. Nanophase Al2O3 (
Lawrence P. Cook, Winnie K. Wong-Ng, Peter K. Schenck, Mark D. Vaudin, J Suh
Over the past decade, ceramic packaging materials have continued to increase in both chemical and structural complexity. At processing temperatures of 800 C to 900 C, the possibilities for interactions at interfaces between dissimilar materials are
L M. Cranswick, W G. Mumme, I E. Grey, Robert S. Roth, P Bordet
The perovskite-related phase Ca 3Nb 2O 8, when grown as single crystals from a calcium vanadate flux, incorporates a smallamount of vanadium from the flux to form the composition Ca 3Nb 2-xV xO 8 with x = 0.025 . The crystals have pseudo-cubicsymmetry with