DSpace at My University: Recent submissions
Now showing items 381-400 of 445
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DIFFUSION OF Ti44 AND V48 IN TITANIUM
(2013-07-03)The diffusion of Ti44 and V48 in the b.c.c. phase of iodide titanium has been studied over the temperature range 909-1550°C. The resulting Arrhenius-type plots show curvature with the apparent activation energies and ... -
Ni Self-Diffusion
(2013-06-26)Self-diffusion in nickel single crystals is measured between 813 and 1193 K using ion-beam sputtering as a microsectioning technique. Gaussian activity-depth profiles are observed over about three orders of magnitude in ... -
Ti-O-M interaction between oxygen and metal (M) substitution in titanium for oxygen diffusion change
(2013-05-28)We calculate first-principles interaction energies between substitutional solutes and oxygen interstitials in α-titanium and predict the effect of solutes on oxygen diffusion from those interactions. Interaction between ... -
Mg-Al Interdiffusion and Phase Growth Kinetics
(2013-05-07)Binary interdiffusion data as functions of composition in the Mg-Al system are essential in modeling kinetics of phase transformations in multicomponent Mg and Al alloys. Interdiffusion and phase growth kinetics were studied ... -
Interdiffusion in the Mg-Al System and Intrinsic Diffusion in beta-Mg2Al3
(2013-05-07)Solid-to-solid diffusion couples were assembled and annealed to examine the diffusion between pure Mg (99.96 pct) and Al (99.999 pct). Diffusion anneals were carried out at 573 K, 623 K and 673 K (300 C, 350 C and 400 C) ... -
Al Impurity Diffusion in Mg
(2013-05-07)The diffusion of Al in polycrystalline Mg (99.9%) was studied via depth profiling with secondary ion mass spectrometry in the temperature range of 573-673 K, utilizing the thin film method and thin film solution to the ... -
Al-Co, Co-Fe Diffusion Mobilities, Ni/Rene88, IN718/Rene88
(2013-05-05)A multicomponent diffusion mobility database for the Ni-rich fcc phase [2002Cam] is evaluated by comparing diffusion simulations to two experimental multicomponent Ni-base superalloy diffusion couples: Ni/Rene´-88 and ... -
TiO2: On the possibility of ferromagnetism
(2013-04-08)To see if ferromagnetism can occur in C-doped anatase TiO2, we performed first-principles calculations for a number of C-doped structures in which C atoms substitute O atoms. Our study shows that each C has spin-polarized ... -
ZrO-X
(2013-04-08) -
PbTiO3: Dipole moment of a Pb-O vacancy pair
(2013-04-08)The polarization of a nearest-neighbor (nn) Pb-O vacancy pair [(VPb-VO)nn] in PbTiO3 is calculated, using the modern theory of polarization, implemented in the density-functional-theory ultrasoft pseudopotential formalism. ... -
SiC-AlN, SiC-GaN and SiC-InN: wurtzite-structure quasibinary systems
(2013-04-08)The cluster-expansion method was used to perform first principles phase diagram calculations for the wurtzite-structure quasibinary systems (SiC)1-X(AlN)X, (SiC)1-X (GaN)X and (SiC)1-X(InN)X; and to model variations of ... -
NaNbO3–KNbO3: Can spinodal decomposition generate relaxor ferroelectricity?
(2013-04-08)First principles based phase diagram calculations were performed for the system (1−X) NaNbO3–(X) KNbO3. Plane wave pseudopotential calculations of formation energies were used as a basis for fitting a cluster expansion ... -
NaCl–KCl: The role of excess vibrational entropy
(2013-04-08)First principles phase diagram calculations were performed for the system NaCl–KCl. Plane-wave pseudopotential calculations of formation energies were used as a basis for fitting cluster expansion Hamiltonians, both with ... -
Hf-Ox First principles phase diagram calculations for the octahedral-interstitial system
(2013-04-03)The group IV hexagonal closest packed (hcp) suboxides MOX (M = Ti, Zr or Hf) all exhibit octahedral interstitial ordering of oxygen, O, and vacancies, in solid solutions of the form View the MathML source, 0≤X≤1/2. By far, ... -
CaCO3-MgCO3 CdCO3–MgCO Subsolidus phase diagrams
(2013-04-03)Planewave pseudopotential calculations of supercell total energies were used as bases for first-principles calculations of the CaCO3–MgCO3 and CdCO3–MgCO3 phase diagrams. Calculated phase diagrams are in qualitative to ... -
Al-Cu-Fe Interdiffusivities and atomic mobilities
(2013-04-01)Using solid/solid diffusion couples and the electron probe microanalysis (EPMA) technique, the interdiffusion coefficients in fcc Cu–Al–Fe alloys at 1273 K were determined by means of Whittle and Green’s method. Based on ... -
Al-Cu-Y Thermodynamic description
(2013-04-01)Phase equilibria in the ternary Al–Cu–Y system have been analyzed by coupling the CALPHAD method and first-principles calculations, and a complete thermodynamic description was obtained. The thermodynamic descriptions of ... -
Si-Sr thermodynamic reassessment
(2013-04-01)The Si–Sr binary system has been thermodynamically reassessed in the present work based on the critically reviewed experimental data available in the literature, especially newly published experimental phase diagram data ... -
Ni-Pb-Sb Experimental investigation and thermodynamic prediction
(2013-04-01)The phase diagram of the ternary Ni–Pb–Sb system was investigated experimentally by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS) methods, and ...