The Earth has a liquid outer and solid inner core. It is predominantly composed of Fe, alloyed with small amounts of light elements, such as S, O and Si. The detailed chemical and thermal structure of the core is poorly constrained, and it is difficult to perform experiments to establish the properties of core-forming phases at the pressures (ca. 300 GPa) and temperatures (ca. 5000-6000 K) to b...

We present high resolution, high SNR spectra of the QSO Q2206-199 obtained with HIRES on the 10m W.M. Keck Telescope. Our analysis focuses on the two previously identified damped Lyα systems found at z = 1.920 and z = 2.076. For the z = 1.920 system, we measure accurate abundances (relative to solar) for Fe, Cr Si, Ni, Ti, and Zn: [Fe/H] = −0.705 ± 0.097, [Cr/H] = −0.580 ± 0.100, [Si/H] = −0.40...

The Fe-Ni-Pb-B alloy nanoparticles was prepared by a solid-solid chemical reaction of ferric trichloride, nickel chloride, lead acetate, and potassium borohydride powders at room temperature. The research results of the ICP and thermal analysis indicate that the resultants are composed of iron, nickel, lead, boron, and PVP, and the component of the alloy is connected with the mole ratio of pota...

Nanocrystalline materials are defined by their fine grain size, but details of the grain boundary character distribution should also be important. Grain boundary character distributions are reported for ball-milled, sputter-deposited, and electrodeposited Ni and Ni-based alloys, all with average grain sizes of ~20 nm, to study the influence of processing route. The two deposited materials had n...

Rhenium Re –Me alloys where Me = Ni, Fe, or Co were deposited galvanostatically. The plating bath consisted of ammonium perrhenate, nickel or cobalt sulfamate, or iron sulfate, citric acid, and magnesium sulfamate. The effects of bath chemistry and deposition time on faradaic efficiency FE , Re content, and partial deposition currents were determined. Rhenium contents as high as 93 atom % or FE...

Sliding wear of nanocrystalline Ni-W alloys with grain sizes from 3 to 45 nm, a range which spans the transition in deformation mechanisms from intrato intergranular, is studied through pin-on-disk wear testing. The extreme conditions produced during sliding wear are found to result in structural evolution and a deviation from Archard scaling for the finest grain sizes; in the finest nanocrysta...

We develop an analytical expression for twin nucleation stress in bcc metal and alloys considering generalized planar fault energy and the dislocations bounding the twin nucleus. We minimize the total energy to predict the twinning stress relying only on parameters that are obtained through atomistic calculations, thus excluding the need for any empirical constants. We validate the present appr...

This is well known that amorphous state is metastable. Metastability of amorphous or glassy metal alloys offers the possibility of phase separation diffusion of various species and structural relaxation even though the alloys remains amorphous when they are annealed at temperature well below the crystallization temperature. All these changes have effect on the intrinsic magnetic properties such...

Introduction: The Widmanstatten pattern develops at low temperatures during the evolution of the asteroids. We have studied the origin of the Widmanstatten pattern in order to obtain metallographic cooling rates in the temperature range (~ 700 to 300 deg C). This paper summarizes our recent evaluation of the various mechanisms for the formation of the Widmanstatten pattern. All chemical groups ...