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Fracture from indentation by a hard sphere on bilayer systems composed of curved brittle coating layers on compliant polymeric substrates is investigated, in simulation of dental crown structures. Glass plates 1 mm thick are used are used as representative
Strength properties of silicon substrates containing dense oxide and nitride surface films are investigated using nanoindentations to introduce small flaws of predetermined scale. The indentation flaws provide favored sites for failure in subsequent
A study is made of fracture from cyclic loading of WC spheres on the surfaces of brittle layers on compliant substrates, as representative of repetitive occlusal contact on dental crowns. Several damage modes radial cracks at both top surface and
A lattice metric singularity occurs when unit cells defining two (or more) lattices yield the identical set of unique calculated d-spacings. The existence of such singularities, therefore, has a practical impact on the indexing of powder patterns. Lattices
Nanotechnology promises to revolutionize a growing set of materials applications ranging from electronics to drug delivery to ballistic protection. However, the quest to engineer mate-rials on the nanoscale (e.g., in the form of ultrathin films) is met
An analytical model providing simultaneous, self-consistent representations of the temperature and porosity dependence of the elastic and bulk moduli of polycrystalline ceramics is applied to data compiled from the literature for 24 oxide ceramics.
L Andruzzi, A Hexemer, X Li, Christopher K. Ober, E K. Kramer, Giancarlo Galli, E Chiellini, Daniel A. Fischer
Surface-grafted styrene-based homopolymer and diblock copolymer brushes bearing semifluorinated alkyl groups were synthesized by nitroxide-mediated controlled radical polymerization on planar silicon oxide surfaces. The polymer brushes were characterized
Andrew J. Allen, J C. McLaughlin, Dan A. Neumann, Richard A. Livingston
The effects of different particle size distributions on the real-time hydration of tricalcium silicate cement paste have beenstudied in situ by quasi-elastic neutron scattering. The changing state of water in the cement system is followed as a functionboth
B D. Huey, C Ramanujan, M Bobji, J Blendell, Grady S. White, R Szoszkiewicz, A Kulik
Piezo-force microscopy (PFM) is a variation of atomic force microscopy that is widely applied to investigate piezoelectric thin films at the nanometer scale. Curiously, PFM experiments are found to be remarkably sensitive to the position along the
Winnie K. Wong-Ng, Qingzhen Huang, Lawrence P. Cook, Igor Levin, James A. Kaduk, Alan D. Mighell, J Suh
Bi 5AgNb 4O 18 is a new phase, which was discovered during the phase equilibrium study of the Bi 2O 3-Ag 2O-Nb 2O 5 system. Bi 5AgNb 4O 18 was prepared at 750 C and is stable in air up to its melting temperature of 1160.1 5.0 C. Results of a Rietveld
The fatigue properties of fine-grain Y-TZP in cyclic flexural testing are studied. Comparative tests on a coarser-grain alumina provide a baseline control. A bilayer configuration with ceramic plates bonded to a compliant polymeric substrate and loaded
Avanced ceramics are being considered as one of the potential materials for high temperature steam engines. Silicon nitride and silicon carbide have demonstrated in laboratory bench wear tests that under low loads and medium speed conditions, water is an
D J. Burnett, A T. Capitano, A M. Gabelnick, A L. Marsh, Daniel A. Fischer, J L. Gland
Temperature programmed and isothermal fluorescence yield measurements have been used to characterize carbon monoxide oxidation on the Pt(111) surface for oxygen pressures from 0.027 Pa to 2.7 Pa over the 200 to 600 K temperature range. Carbon monoxide
S Sambasivan, Daniel A. Fischer, M C. Shen, Stephen M. Hsu
Wear and wear debris of ultra-high molecular weight polyethylene (UHMWPE) in joint replacements has been recognized as one of the major contributors to the failure of orthopaedic implants. Detailed wear mechanisms of the polyethylene under biomechanic
Winnie K. Wong-Ng, Lawrence P. Cook, Igor Levin, J Suh, Ron Feenstra, T J. Haugan, P. D. Barnes
Phase diagrams of the Ba 2RCu 3O 6+x (R=Nd, Sm, Gd, Y, and Er) superconductors, prepared under 0.1 % 0 2 at 810 C, reflect the trend of the lanthanide contraction. The single-phase regions of Ba 2-x(Nd 1+x-yR y) Cu 3O 6+z for R=Gd, Y and Yb, and Ba 2-x(R 1
N G. Armstrong, W Kalceff, James Cline, John E. Bonevich
A Bayesian/Maximum Entropy (MaxEnt) method for determining crystallite size distribution and morphology from size-broadened x-ray line profiles is presented. This method will be used in certifying a nanocrystallite-size standard reference material (SRM)