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Igor Levin, M Stennett, I Reaney, G Miles, D I. Woodward, C Kirk, A R. West
The structure and dielectric properties of a new family of tetragonal tungsten bronze structured ceramics with the general formula, Ba 2ReNb 3Ti 2O 15 (BReNTO 15,Re=Bi 3+,La 3+,Nd 3+,Sm 3+,Gd 3+) have been investigated. BLNTO15 Tmax -100 C) and BBNTO15
Atomic force microscopy measurements of the piezoelectric response of a lead zirconate titanate (PZT) thin film detect domain pinning sites along grain boundaries. The locations of these sites are reproducible and 180 degrees domains appear to extend from
The Frank-Bilby equation (FBE) can give many solutions for the dislocation content of a grain boundary (GB); most of them are considered to have little physical reality except in limited ranges of the angles which characterize low-angle GBs. We explore two
Interface wear behavior and its effects on the shear frictional sliding resistance in fiber-reinforced ceramics have been studied using SiC fiber (SCS-6)-reinforced A1203 matrix composite. Thin specimen pushout tests were performed and surface wear
Mechanisms of energy dissipation during solid-solid and solid-liquid friction are discussed. A conservative van der Waals adhesion force, when combined with surface imperfectness, such as deformation, leads to adhesion histeresis (AH). When an asperity
We have uncovered the fact that colloidal probes often have random surface features which when not properly accounted for, can significantly affect the magnitudes of the measured adhesive forces using atomic force microscopes (AFM). Colloidal probes have
Julia Slutsker, Igor Levin, Jiying Li, Andrei Artemev, Alexander L. Roytburd
The theoretical and experimental studies of self-assembled multiferroic nanostructures in epitaxial films were combined to reveal the dominant role of elastic interactions, as caused by expitaxial stresses during growth, in defining the nanostructure
Wear tests were conducted using a pin-on-disk tribometer to evaluate the effect of disk track diameter on the tribological behavior. High purity alumina balls were used as pins sliding against glass-ceramic (IPS empress 2) disks under distilled water
This paper addresses issues of fracture for materials in which large grains, exist in a matrix of much smaller grains. Materials used for optical components, such as ZnS and ZnSe frequently fall into this category. For materials of this sort failure can
Boundary migration of ZnO has been investigated using single crystals with defined crystallographic orientations. The migration rate of the basal C planes depended on the crystallographic polarity: Zn-terminated positive (0001)-planes. The migration in the
ramic thermal barrier coatings (TBC) can exhibit premature in-service failure due to spallation as a consequence of exposure to elevated temperatures, aggressive environments, and cyclic loading. Lifetime assessment for TBC-systems requires methods for
The hole mobility and carrier lifetime of [alpha] mercuric iodide high energy radiation detectors have been enhanced through crystal growth in microgravity. The improvement is closely correlated with specific characteristics of the crystal lattice, which