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We estimated the magnetic damping constant a of Co2FeAl (CFA) Heusler alloy films of different thicknesses with an MgO capping layer by means of time-resolved magneto-optical Kerr effect and ferromagnetic resonance measurements. CFA films with thicknesses of 1.2 nm and below exhibited perpendicular magnetic anisotropy arising from the presence of the interface with MgO. While a increased gradually with decreasing CFA film thickness down to 1.2 nm, it was increased substantially when the thickness was reduced further to 1.0 nm. Based on the microstructure analyses and first-principles calculations, we attributed the origin of the large a in the ultrathin CFA film primarily to the Al deficiency in the CFA layer, which caused an increase in the density of states and thereby in the scatterings of their spins. [ABSTRACT FROM AUTHOR]

This work describes a correlation among texture, in-plane anisotropy in tensile properties, and yield locus in Ni-based Hastelloy C-276 alloy. The alloy exhibits moderate values of in-plane anisotropy and anisotropy index, which has been attributed to the presence of moderate overall intensity of texture. The alloy displays two slopes in true plastic stress-strain curve and follows a Ludwigson relation. At low plastic strains, the sample displays the presence of annealing twins and less strain localization at grain boundaries, while the formation of deformation twins and high strain localization within the deformation twins and at the grain boundaries are observed in a high-strained region. The 45-deg and 67.5-deg orientation samples show relatively low ductility and low work-hardening exponent. This has been explained based on dislocation storage capacity and dynamic recovery coefficient using Kock-Mecking-Estrin analysis. [ABSTRACT FROM AUTHOR]

The present work describes the phase transformation textures of three alloys, namely Ti-8Nb, Ti-12Nb, and Ti-16Nb after β and α + β solution treatments with different cooling rates. The strong, moderate, and weak variant selections have been observed depending on the alloy compositions and cooling rates. The β solution treated and water quenched (STWQ) specimens always exhibit a higher overall intensity than those of β solution treated and furnace cooled (STFC) specimens. This has been attributed to the presence of β phase, which has inhibited the growth of selected variants during cooling. The evidence of texture memory has also been observed after α → β→ α and α″ → β → α″ transformations. A combined effect of α, β, and ω phases has introduced different textures after α+ β heat treatment than those of β heat-treated specimens. Extent of anisotropy in pole figures is more in water quenched (WQ) than those of furnace cooling (FC) specimens due to the development of equivalent orientations of individual crystallites during slow cooling. [ABSTRACT FROM AUTHOR]

Optically induced spin waves in Ni80Fe20 (permalloy) cross-shaped nanoelements are studied by time-resolved magneto-optical Kerr effect microscope. A strong anisotropy in the spin wave modes are observed with the orientation angle ([lowercase_phi_synonym]) of the in-plane bias magnetic field. As [lowercase_phi_synonym] deviates from 0° a single resonant mode splits into a numbers of modes, while the powers of the higher frequency modes increase as [lowercase_phi_synonym] increases from 0 to 45°. The lowest frequency mode shows a four-fold configurational anisotropy. The mode of a single cross remains unaffected by the magnetostatic interaction of the neighbouring elements for [lowercase_phi_synonym] = 0°, while the effect increases with [lowercase_phi_synonym] and becomes maximum at 45°, making these elements interesting candidates as building blocks for magnonic devices. [ABSTRACT FROM AUTHOR]

The anisotropy in the collective precessional dynamics with the variation of azimuthal angle of the bias magnetic field is studied in arrays of permalloy (Ni80Fe20) nanoelements by an all-optical time-resolved Kerr microscope. When the nanoelements are very closely spaced (inter-element separation = 50 nm), a gradual transition from completely uniform collective regime to a completely non-collective regime is observed as the azimuthal angle varies from 0° to 45°. On the other hand, for inter-element separation of 100 nm, a non-uniform collective dynamics is observed at 0° and a non-collective dynamics is observed at 45° but no clear trend in the transition is observed. [ABSTRACT FROM AUTHOR]

We present an all-optical time-resolved measurement of dipole-exchange spin wave spectra in a series of CoO capped [Co(t)/Pt(7 Å)]n-1 Co(t) multilayer systems, where the total Co moment (n × t) is constant. In general, the spectra consist of two intense peaks and additional lower intensity peaks. The observed spin wave modes are modeled by a discrete dipole approximation. The frequency of the spin wave bands depends significantly upon the magnetic anisotropy and the lattice spacing between planes. Both symmetric and anti-symmetric modes are observed from the calculation of the spin-wave profiles across the multilayer in the out-of-plane direction. [ABSTRACT FROM AUTHOR]

Present work describes a correlation amongst texture, in-plane anisotropy in tensile properties and yield locus in Ni-20Cr-8Fe alloy. The alloy exhibits high and moderate values of in-plane anisotropy and anisotropy index, respectively. This has been attributed to the presence of moderate overall intensity of texture as well as partially recrystallized microstructure. The tensile properties evaluated in five sample directions, namely the 0° (longitudinal or L), 22.5°, 45°, 67.5° and 90° (transverse or T) to the rolling direction, display two slopes in true plastic stress-strain curve and follow a Ludwigson relation. At low strains, sample displays the presence of annealing twins and less strain localization (1.5-3.5° boundaries) while the formation of deformation twins and high strain localization are observed in high strained region. The 67.5° orientation sample shows relatively low ductility and low work hardening exponent. This has been explained using Kock-Mecking-Estrin analysis based on higher degree of dynamic recovery/glide softening and fluctuations in work hardening rate during stage II. [ABSTRACT FROM AUTHOR]