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The mechanical behavior of Zr-based bulk amorphous alloy composites (BAACs) was investigated at 77 K. The 5 vol. % Ta-BAAC maintained large plastic strains of approximately 13% with a 16% strength increase, when compared with that at 298 K. The interaction between shear bands and particles shows that shear extension in particles has limited penetration, and(More)
As materials functionality becomes more dependent on local physical and electronic properties, the importance of optically probing matter with true nanoscale spatial resolution has increased. In this work, we mapped the influence of local trap states within individual nanowires on carrier recombination with deeply subwavelength resolution. This is achieved(More)
Using first-principles theory and experiments, chemical contributions to surface-enhanced Raman spectroscopy for a well-studied organic molecule, benzene thiol, chemisorbed on planar Au(111) surfaces are explained and quantified. Density functional theory calculations of the static Raman tensor demonstrate a strong mode-dependent modification of benzene(More)
Nucleation in the undercooled liquid state in the bulk metallic glass-forming composition Zr 52.5 Cu 17.9 Ni 14.6 Al 10 Ti 5 ͑VIT-105͒, produced using high purity ͑PA͒ and commercial purity ͑CA͒ raw materials was investigated using electrostatic levitation and ex situ neutron diffraction. The CA material was observed to have a lower density than the PA(More)
The evolution of temperature and thermal stresses during friction stir welding of Al6061-T6 was investigated by means of in situ, time resolved neutron diffraction technique. A method was developed to deconvolute the temperature and stress from the lattice spacing changes measured by neutron diffraction. The deep penetration capability of neutrons made it(More)
The residual strain profiles were measured through the thickness of friction-stir welded (FSW) plates using neutron diffraction to study the relationship between the angular distortion and the residual strain distribution. Three different weld specimens were prepared from a 6061-T6 aluminum alloy with the purpose of separating the effects of the frictional(More)
The deformation behavior as a function of applied strain was studied in a nanostructured Ni-Fe alloy using the in situ synchrotron diffraction technique. It was found that the plastic deformation process consists of two stages, undergoing a transition with applied strain. At low strains, the deformation is mainly accommodated at grain boundaries, while at(More)
A nanocrystalline (NC) NiFe alloy is presented, in which both highly improved plasticity and strength are achieved by the dynamic-loading-induced deformation mechanisms of de-twinning (that is, reduction of twin density) and significant grain coarsening. This work highlights potential ingenious avenues to exploit the superior behavior of NC materials under(More)
The effect of hydrogen charging on the lattice dilation in an ASTM A710-HSLA steel specimen was studied using neutron diffraction. First, spatially-resolved strain measurements were made on a pre-cracked steel double cantilever beam specimen under a constant crack opening displacement (COD). Measurements were made at the crack tip region for in-plane and(More)
The low-cycle fatigue behavior of a cobalt-based superalloy was studied in-situ using neutron-diffraction experiments. The alloy exhibited a strain-induced formation of a hexagonal-close-packed (hcp) phase within its parent face-centered-cubic (fcc) phase at ambient temperature under strain-controlled fatigue conditions with a total strain range, ∆ε = 2.5%.(More)
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