Temperature Dependence of Twinning Pseudoelasticity in Fe<SUB>3</SUB>Ga Single Crystals

Phase-Field Analysis of Fracture-Induced Twinning in Single Crystals

Deformation twinning at the tip of a straight crack or notch is analyzed using a phase-field method that seeks equilibrium twin morphologies via direct minimization of a free energy functional. For isotropic solids, the tendency to twin under mode I or mode II loading is found to depend weakly on Poisson’s ratio and elastic nonlinearity and strongly on surface energy and twinning shear (i.e. ei...

Investigation into the temperature dependence of isotropic- nematic phase transition of Gay- Berne liquid crystals

Density functional approach was used to study the isotropic- nematic (I-N) transition and calculate the values of freezing parameters of the Gay- Berne liquid crystal model. New direct and pair correlation functions of a molecular fluid with Gay- Berne pair potential were used. These new functions were used in density functional theory as input to calculate the isotropic- nematic transition den...

Influence of Plastic Deformation on the Temperature Dependence of Ultrasonic Attenuation in Copper Single Crystals

The influence of plastic deformation (O<&<10%) on the MHz-ultrasonic attenuation a in single crystals of pure Cu, Cu50ppmAu and Cul30ppmAu has been measured over the temperature range 4<T<300K. The major contributions to the total attenuation originate from dislocation resonance, double-kink relaxation, phonon-electron interaction (at T<50K) and non-dislocation effects which are discussed espec...

Temperature and strain-rate dependence of the flow stress of tantalum single crystals in cyclic deformation

Topology and temperature dependence of the diffuse X-ray scattering in Na0.5Bi0.5TiO3 ferroelectric single crystals.

The results of high-resolution measurements of the diffuse X-ray scattering produced by a perovskite-based Na0.5Bi0.5TiO3 ferroelectric single crystal between 40 and 620 K are reported. The study was designed as an attempt to resolve numerous controversies regarding the average structure of Na0.5Bi0.5TiO3, such as the mechanism of the phase transitions between the tetragonal, P4bm, and rhombohe...