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2018-10-18
Coating of Aluminum Alloys by Micro Arc Oxidation in Nitrate Salt
Plasma electrolytic oxidation (PEO) is a process for obtaining oxide coatings on valve metals. Mostly PEO is done in an aqueous solution electrolyte which limits the size of treated parts due to the system heating up. In presented work an alternative method of PEO processing applied in aluminum 1050 alloy in nitrate mo...
1810.08018v1
2018-10-23
Ultra-low Hysteresis in Giant Magnetocaloric Mn1-xVxFe(P,Si,B) Compounds
Large thermal hysteresis in the MnFe(P, Si, B) system hinders the heat exchange rate and thus limits the magnetocaloric applications at high frequencies. Substitution of Mn by V in Mn1-xVxFe0.95P0.593Si0.33B0.077 and Mn1-xVxFe0.95P0.563Si0.36B0.077 alloys was found to reduce the thermal hysteresis due to a decrease in ...
1810.09902v1
2019-01-21
Non-collinear coupling across RuCo and RuFe alloys
Spintronic applications, which rely on spin torques for operation, would greatly benefit from a non-collinear alignment between magnetizations of adjacent ferromagnetic layers for maximum performance and reliability. We demonstrate that such an alignment can be created and controlled by coupling two ferromagnetic layer...
1901.07055v1
2019-01-22
Atomistic Relaxation Process in a Ni3Al Ordered Phase Using Path Probability Method with Vacancy Mechanisms
The path probability method (PPM), which is a natural extension of the cluster variation method (CVM) to a time domain, has been employed in a relaxation process of atomic configurations in alloy systems. Although the vacancy mechanism is the main atomic migration process in an alloy system, most studies of PPM have us...
1901.07210v1
2019-04-03
Amorphous Intergranular Films Enable the Creation of Bulk Nanocrystalline Cu-Zr with Full Density
Nanocrystalline metal alloys show great potential as structural materials, but are often only available in small volumes such as thin films or powders. However, recent research has suggested that dopant segregation and grain boundary structural transitions between states known as complexions can dramatically alter grai...
1904.02230v2
2019-04-09
Corrosion studies on Fe-30Mn-1C alloy in chloridecontaining solutions with view to biomedical application
Austenitic Fe-30Mn-1C (FeMnC) is a prospective biodegradable implant material combining high mechanical integrity with adequate corrosion rates. The fast solidified TWIP alloy, its constituents and 316L stainless steel were electrochemically analysed in various electrolytes at 37 {\deg}C under laminar flow. Potentiodyn...
1904.04611v1
2019-04-11
From diffusion experiments to mean-field theory simulations and back
Using previous experimental data of diffusion in metallic alloys, we obtain real values for an interpolation parameter introduced in a mean-field theory for diffusion with interaction. Values of order 1 were found as expected, finding relevance for this quantity as a way to better understand the underlying dynamics of ...
1904.05799v2
2019-04-15
Evolution of interfacial dislocation network during low-stress high temperature creep of particle strengthened alloy system using discrete dislocation dynamics simulations
We use three-dimensional discrete dislocation dynamics simulations (DDD) to study the evolution of interfacial dislocation network (IDN) in particle-strengthened alloy systems subjected to constant stress at high temperatures. We have modified the dislocation mobility laws to incorporate the recovery of the dislocation...
1904.08768v1
2019-04-25
Annealing driven positive and negative exchange bias in Fe-Cu-Pt heterostructures at room temperature
We report annealing induced exchange bias in Fe-Cu-Pt based heterostructures with Cu as an intermediate layer (Fe/Cu/Pt heterostructure) and capping layer (Fe/Pt/Cu heterostructure). Exchange bias observed at room temperature (300 K) is found to be dependent on the annealing temperature. We obtained positive exchange b...
1904.11270v1
2019-07-02
Exploring effective charge in electromigration using machine learning
The effective charge of an element is a parameter characterizing the electromgration effect, which can determine the reliability of interconnection in electronic technologies. In this work, machine learning approaches were employed to model the effective charge (z*) as a linear function of physically meaningful element...
1907.01480v1
2019-07-14
High entropy alloy superconductors -- status, opportunities and challenges
High entropy alloys (HEAs) are a recently-opened research area in materials science and condensed matter physics. Although 3d-metal-based HEAs have already been the subject of many investigations, studies of HEA superconductors, which tend to be based on 4d metals, are relatively fewer. Here we provide a short update o...
1907.06195v2
2019-10-01
Unique Dirac and Triple point fermiology in simple transition metals and their binary alloys
Noble metal surfaces (Au, Ag and Cu etc.) have been extensively studied for the Shockley type surface states (SSs). Very recently, some of these Shockley SSs have been understood from the topological consideration, with the knowledge of global properties of electronic structure. In this letter, we show the existence of...
1910.00196v2
2019-10-08
Analytical Models of Phonon-Point Defect Scattering
Point defects exist widely in engineering materials and are known to scatter vibrational modes to reduce thermal conductivity. The Klemens description of point defect scattering is the most prolific analytical model for this effect. This work reviews the essential physics of the model and compares its predictions to fi...
1910.03654v1
2019-10-09
Understanding plasticity in zirconium using in-situ measurement of lattice rotations
Understanding deformation in polycrystalline metals is critical to use them in high-value high-risk applications. We present in-situ characterisation of plastic deformation of zirconium, a hexagonal closed packed (HCP), metal. Analysis of plastic deformation is performed using electron backscatter diffraction (EBSD) to...
1910.04187v1
2019-10-11
Branching of twins in shape memory alloys revisited
We study the branching of twins appearing in shape memory alloys at the interface between austenite and martensite. In the framework of three-dimensional non-linear elasticity theory, we propose an explicit, low-energy construction of the branched microstructure, generally applicable to any shape memory material withou...
1910.05235v1
2019-10-22
Post-Heat Treatment Design of High-Strength Low-Alloy Steels Processed by Laser Powder Bed Fusion
In this study, a post-heat treatment design for additively manufactured copper-bearing high-strength low-alloy (HSLA)-100 steel is performed by understanding the process-structure-property relationships. Hot isostatic pressing (HIP) is designed to reduce the porosity from 3% to less than 1% for the HSLA-100 steel proce...
1910.09939v3
2012-09-01
Spin-Hall Effect and Diamagnetism of Dirac Electrons
Spin-Hall conductivity (SHC) of fully relativistic (4x4 matrix) Dirac electrons is studied based on the Kubo formula aiming at possible application to bismuth and bismuth-antimony alloys. It is found that there are two distinct contributions to SHC, one only from the states near the Fermi energy and the other from all ...
1209.0092v1
2012-09-07
Influence of severe plastic deformation on the precipitation hardening of a FeSiTi steel
The combined strengthening effects of grain refinement and high precipitated volume fraction (~6at.%) on the mechanical properties of FeSiTi alloy subjected to SPD processing prior to aging treatment were investigated by atom probe tomography and scanning transmission electron microscopy. It was shown that the refineme...
1209.1608v1
2012-09-14
Concentration dependence in kinetic arrest of first order magnetic transition in Ta doped $HfFe_2$
Magnetic behavior of the pseudo-binary alloy $Hf_{1-x}Ta_xFe_2$ has been studied, for which the zero field ferromagnetic (FM) to antiferromagnetic (AFM) transition temperature is tuned near to T=0 K. These alloys show anomalous thermomagnetic irreversibility at low temperature due to kinetic arrest of the first order A...
1209.3177v1
2012-09-15
Work hardening behavior in a steel with multiple TRIP mechanisms
Transformation induced plasticity (TRIP) behavior was studied in steel with composition Fe-0.07C-2.85Si-15.3Mn-2.4Al-0.017N that exhibited two TRIP mechanisms. The initial microstructure consisted of both {\epsilon}- and {\alpha}-martensites with 27% retained austenite. TRIP behavior in the first 5% strain was predomin...
1209.3410v1
2012-09-21
Dominant itinerant ferromagnetism in Eu0.5Sr0.5CoO3: evidences from both critical analysis and Rhodes-Wohlfarth's criterion
The critical behaviors of ferromagnet Eu0.5Sr0.5CoO3 arround TC=140.5K have been comprehensively investigated by analyzing a series of isothermal magnetization M(H) curves. Both Modified Arrott plot and Kouvel-Fisher methods give nearly the same critical exponents, which scale nicely the M(H) curves into two different ...
1209.4790v2
2012-09-28
Evaluating the role of Lead In A Novel Ternary Catalysts For DMFCs
The current density at lower potential is highly desirable in fuel cell technology and crucial center point for designing a new catalyst. By alloying platinum with various other metals, the improvisation of the fuel cell catalyst has achieved a lot of attention and interests. In this article, a novel porous ternary all...
1209.6629v1
2014-06-06
Near-forward Raman study of a phonon-polariton reinforcement regime in the Zn(Se,S) alloy
We investigate by near-forward Raman scattering a presumed reinforcement of the (A-C,B-C)-mixed phonon-polariton of a A1-xBxC zincblende alloy when entering its longitudinal optical (LO-)regime near the Brillouin zone centre {\Gamma}, as predicted within the formalism of the linear dielectric response. A choice system ...
1406.1763v2
2014-06-09
Diffusion behavior in Nickel-Aluminium and Aluminium-Uranium diluted alloys
Impurity diffusion coefficients are entirely obtained from a low cost classical molecular statics technique (CMST). In particular, we show how CMST is appropriate in order to describe the impurity diffusion behavior mediated by a vacancy mechanism. In the context of the five-frequency model, CMST allows to calculate al...
1406.2239v1
2014-06-10
Skew scattering in dilute ferromagnetic alloys
The challenging problem of skew scattering for Hall effects in dilute ferromagnetic alloys, with intertwined effects of spin-orbit coupling, magnetism and impurity scattering, is studied here from first principles. Our main aim is to identify chemical trends and work out simple rules for large skew scattering in terms ...
1406.2712v2
2018-02-03
Magnon scattering in the transport coefficients of CoFe alloys
Resistivity $\rho$, thermopower ${\cal S}$, and thermal conductivity $\kappa$ were measured simultaneously on a set of CoFe alloy films. Variation of the Co-content $x_\mathrm{Co}$ allows for a systematic tuning of the Fermi level through the band structure, and the study of the interplay between electronic and magneti...
1802.01038v1
2018-02-26
Evolution of passive film behavior on mechanically polished NiTi shape memory alloy during forward martensitic transformation
The corrosion property of Nickel-titanium (NiTi) shape memory alloy is investigated during forward martensitic transformation between 40C and 0C. The Differential Scanning Calorimetry technique is used to find the forward and reverse martensitic transformation temperatures. NiTi shows the present of martensitic phase a...
1802.09606v2
2018-08-10
Pattern Learning Electronic Density of States
Electronic density of states (DOS) is a key factor in condensed matter physics and material science that determines the properties of metals. First-principles density-functional theory (DFT) calculations have typically been used to obtain the DOS despite the considerable computation cost. Herein, we report a fast patte...
1808.03383v1
2018-12-06
Crack Growth Behavior in NiTi Shape Memory Alloys Under Mode-I Isothermal Loading: Effect of Stress State
Fracture behavior in nickel-titanium (NiTi) shape memory alloys (SMAs) subjected to mode-I, isothermal loading is studied using finite element analysis (FEA). Compact tension (CT) SMA specimen is modeled in Abaqus finite element suite and crack growth under displacement boundary condition is investigated for plane stra...
1812.02362v1
2018-12-13
A Finite Strain Constitutive Model Considering Transformation Induced Plasticity for Shape Memory Alloys under Cyclic Loading
Many engineering applications of Shape Memory Alloys (SMAs) involve passing back and forth through phase transformation many times. Repeated phase transformation develops permanent deformations originating from the significant distortion that phase transformation induces at the austenite-martensite interfaces and grain...
1812.05695v2
2018-12-15
Enabling visible-light absorption and p-type doping in In2O3 by adding Bi
In2O3 is a prototype wide-band-gap semiconductor that exhibits metallic conductivity when highly doped with Sn while retaining a high degree of transparency to visible light. It is widely used as a transparent window/electrode in solar cells and LEDs. The functionality of In2O3 would be greatly extended if p-type condu...
1812.06353v1
2018-12-18
The role of β-titanium ligaments in the deformation of dual phase titanium alloys
Multiphase titanium alloys are critical materials in high value engineering components, for instance in aero engines. Microstructural complexity is exploited through interface engineering during mechanical processing to realise significant improvements in fatigue and fracture resistance and strength. In this work, we e...
1812.07250v2
2018-12-20
Charge Density Wave Modulation in Superconducting BaPbO$_3$/BaBiO$_3$ Superlattices
The isotropic, non-magnetic doped BaBiO$_3$ superconductors maintain some similarities to high-Tc cuprates, while also providing a cleaner system for isolating charge density wave (CDW) physics that commonly competes with superconductivity. Artificial layered superlattices offer the possibility of engineering the inter...
1812.08589v1
2019-02-12
Suppression of Shastry-Sutherland phase driven by electronic concentration reduction in magnetically frustrated Ce$_2$Pd$_2$Sn$_{1-y}$In$_y$ alloys
Shastry-Sutherland lattice was observed as alternative ground state in Rare Earth intermetallic with Mo$_2$B$_2$Fe and U$_2$Pt$_2$Sn anisotropic structures where magnetic frustration is favored. In the case of Ce$_2$Pd$_2$Sn, it was shown that such phase can be suppressed by the application of magnetic field and, in th...
1902.04540v1
2019-02-03
Design of Face Centered Cubic Co81.8Si9.1B9.1 with High Magnetocrystalline Anisotropy
Despite the composition close to glassy forming alloys, face centered cubic (FCC) Co81.8Si9.1B9.1, designed based on Co9B atomic cluster (polyhedral), are synthesized as singlephase ribbons successfully. These ribbons, with grain sizes of ca. 92 nm, show supreme ductility and strong orientation along (111), which coupl...
1902.05120v1
2019-02-20
Beyond scaling relations for the description of catalytic materials
Computational screening for new and improved catalyst materials relies on accurate and low-cost predictions of key parameters such as adsorption energies. Here, we use recently developed compressed sensing methods to identify descriptors whose predictive power extends over a wide range of adsorbates, multi-metallic tra...
1902.07495v1
2019-02-23
Competitive B2 and B33 Nucleation during Solidification of Ni50Zr50 Alloy: Molecular Dynamics Simulation and Classical Nucleation Theory
We investigated the homogenous nucleation of the stoichiometric B2 and B33 phases in the Ni50Zr50 alloy using the persistent embryo method and the classical nucleation theory. The two phases become very close competitors at large supercoolings, which is consistent with the experimental observations. In the case of the ...
1902.08865v1
2019-06-03
Bismuth-doped Ga2O3 as candidate for p-type transparent conducting material
Gallium oxide (Ga2O3) is a wide-band-gap semiconductor promising for UV sensors and high power transistor applications, with Baliga's figure of merit that far exceeds those of GaN and SiC, second only to diamond. Engineering its band structure through alloying will broaden its range of applications. Using hybrid densit...
1906.00840v1
2019-06-08
Lifschitz tail for alloy-type models driven by the fractional Laplacian
We establish precise asymptotics near zero of the integrated density of states for the random Schr\"{o}dinger operators $(-\Delta)^{\alpha/2} + V^{\omega}$ in $L^2(\mathbb R^d)$ for the full range of $\alpha\in(0,2]$ and a fairly large class of random nonnegative alloy-type potentials $V^{\omega}$. The IDS exhibits the...
1906.03419v1
2019-06-12
Unfolding the complexity of quasi-particle physics in disordered materials
The concept of quasi-particles forms the theoretical basis of our microscopic understanding of emergent phenomena associated with quantum mechanical many-body interactions. However, quasi-particle theory in disordered materials has proven difficult, resulting in the predominance of mean-field solutions. Here we report ...
1906.04945v1
2019-06-14
Possibility of suppression of the formation of solute-enriched clusters
Based on the earlier proposed mechanism of formation of solute-enriched clusters in irradiated pressure vessel steels, it has been demonstrated that it is possible to suppress this process by the method of light alloying of PVS with a chemical element with specially selected properties such as solubility, activity, and...
1906.06030v1
2019-06-16
Polytetrahedral short-range order and crystallization stability in supercooled ${\rm Cu_{64.5}Zr_{35.5}}$ metallic liquid
Development of reliable interatomic potentials is crucial for theoretical studies of relationship between chemical composition, structure and observable properties in glass-forming metallic alloys. Due to ambiguity of potential parametrization procedure, some crucial properties of the system, such as crystallization st...
1906.06689v1
2019-06-17
Photorealistic modelling of metals from first principles
The colours of metals have attracted the attention of humanity since ancient times, and coloured metals, in particular gold compounds, have been employed for tools and objects symbolizing the aesthetics of power. In this work we develop a comprehensive framework to obtain the reflectivity and colour of metals, and show...
1906.06942v1
2019-06-28
Variance reduction for effective energies of random lattices in the Thomas-Fermi-von Weizsäcker model
In the computation of the material properties of random alloys, the method of "special quasirandom structures" attempts to approximate the properties of the alloy on a finite volume with higher accuracy by replicating certain statistics of the random atomic lattice in the finite volume as accurately as possible. In the...
1906.12245v1
2020-04-09
Prediction of mechanical properties of non-equiatomic high-entropy alloy by atomistic simulation and machine learning
High-entropy alloys (HEAs) with multiple constituent elements have been extensively studied in the past 20 years due to their promising engineering application. Previous experimental and computational studies of HEAs focused mainly on equiatomic or near equiatomic HEAs. However, there is probably far more treasure in t...
2004.04439v1
2020-04-10
Alloying V in MnBi$_2$Te$_4$ for Robust Ferromagnetic Coupling and Quantum Anomalous Hall Effect
The intrinsic antiferromagnetic (AFM) interlayer coupling in two-dimensional magnetic topological insulator MnBi$_2$Te$_4$ places a restriction on realizing stable quantum anomalous Hall effect (QAHE) [Y. Deng et al., Science 367, 895 (2020)]. Through density functional theory calculations, we demonstrate the possibili...
2004.04862v2
2020-04-17
Electromigration-guided composition patterns in thin alloy films: a computational study
Via computation of a continuum dynamical model of the diffusion and electromigration, this paper demonstrates the feasibility of guiding the formation of the stripe composition patterns in the thin surface layers of the crystal alloy films. By employing the systematic parametric computational analysis it is revealed ho...
2004.08314v1
2020-04-20
Stochastic Peierls-Nabarro Model for Dislocations in High Entropy Alloys
High entropy alloys (HEAs) are single phase crystals that consist of random solid solutions of multiple elements in approximately equal proportions. This class of novel materials have exhibited superb mechanical properties, such as high strength combined with other desired features. The strength of crystalline material...
2004.09375v1
2020-05-06
Two-Dimensional Rare Earth -- Gold Intermetallic Compounds on Au(111) by Surface Alloying
Surface alloying is a straightforward route to control and modify the structure and electronic properties of surfaces. Here, We present a systematical study on the structural and electronic properties of three novel rare earth-based intermetallic compounds, namely ReAu2 (Re = Tb, Ho, and Er), on Au(111) via directly de...
2005.02660v1
2020-05-07
Origin of the Significant Impact of Ta on the Creep Resistance of FeCrNi Alloys
Heat resistant FeCrNi alloys are widely used in the petrochemical industry because they exhibit a unique combination of creep and oxidation resistance at temperatures exceeding 900$^\circ$C. Their creep properties are often optimized by micro-additions of carbide forming elements. In the present work, the influence of ...
2005.03309v1
2020-05-07
Intragranular nucleation of tetrahedral precipitates and discontinuous precipitation in Cu-5wt%Ag
Both continuous and discontinuous precipitation is known to occur in CuAg alloys. The precipitation of Ag-rich phase has been experimentally investigated by atom probe tomography and transmission electron microscopy after ageing treatment of Cu-5%wtAg at 440$^\circ$C during 30'. Both continuously and discontinuously fo...
2005.03313v1
2020-05-09
Spectral Neural Network Potentials for Binary Alloys
In this work, we present a numerical implementation to compute the atom centered descriptors introduced by Bartok et al (Phys. Rev. B, 87, 184115, 2013) based on the harmonic analysis of the atomic neighbor density function. Specifically, we focus on two types of descriptors, the smooth SO(3) power spectrum with the ex...
2005.04332v2
2020-05-09
Elinvar effect in $β-$Ti simulated by on-the-fly trained moment tensor potential
A combination of quantum mechanics calculations with machine learning (ML) techniques can lead to a paradigm shift in our ability to predict materials properties from first principles. Here we show that on-the-fly training of an interatomic potential described through moment tensors provides the same accuracy as state-...
2005.04375v1
2020-05-27
Spin-valley dynamics in alloy-based transition metal dichalcogenide heterobilayers
Van der Waals heterobilayers based on 2D transition metal dichalcogenides have been recently shown to support robust and long-lived valley polarization for potential valleytronic applications. However, the role of the band structure and alignment of the constituent layers in the underlying dynamics remains largely unex...
2005.13306v2
2020-08-17
Giant Magnetic-Field-Induced Strain in Ni2MnGa-based polycrystal
Ferromagnetic Ni2MnGa-based alloys play an important role in technological fields, such as smart actuators, magnetic refrigeration and robotics. The possibility of obtaining large non-contact deformation induced by an external perturbation is one of its key strengths for applications. However, the search for materials ...
2008.07569v1
2020-08-18
First-principles study of exchange coupling constants in Nd$_x$Fe$_{1-x}$ amorphous alloy
We investigate the exchange coupling constant $J_{ij}$ in Nd$_x$Fe$_{1-x}$ amorphous alloys with different compositions within the framework of first-principles calculation. We observed a strong atomic-dependence of $J_{ij}$ and its fluctuations. We show that the composition strongly affects the distance dependence of ...
2008.07735v1
2020-08-19
Analysis of Phase Formations and Mechanical Properties in Complex Concentrated Alloys by Machine Learning Approach
The mechanical properties of complex concentrated alloys (CCAs) depend on their forming phases and corresponding structures, the prediction of the phase formation for a given CCA is essential to its discovery and applications. 541 sample were collected from previous studies, comprising 61 amorphous, 164 single-phase cr...
2008.08341v1
2020-08-26
Accurate Deep Potential model for the Al-Cu-Mg alloy in the full concentration space
Combining first-principles accuracy and empirical-potential efficiency for the description of the potential energy surface (PES) is the philosopher's stone for unraveling the nature of matter via atomistic simulation. This has been particularly challenging for multi-component alloy systems due to the complex and non-li...
2008.11795v2
2021-03-02
Neural evolution structure generation: High Entropy Alloys
We propose a method of neural evolution structures (NESs) combining artificial neural networks (ANNs) and evolutionary algorithms (EAs) to generate High Entropy Alloys (HEAs) structures. Our inverse design approach is based on pair distribution functions and atomic properties and allows one to train a model on smaller ...
2103.01462v1
2021-03-02
Single Alloy Nanoparticle X-Ray Imaging during a Catalytic Reaction
The imaging of active nanoparticles represents a milestone in decoding heterogeneous catalysts dynamics. We report the facet resolved, surface strain state of a single PtRh alloy nanoparticle on SrTiO3 determined by coherent x-ray diffraction imaging under catalytic reaction conditions. Density functional theory calcul...
2103.01573v1
2021-03-07
Amorphous complexions alter the tensile failure of nanocrystalline Cu-Zr alloys
Grain boundary-based mechanisms are known to control the plastic deformation and failure of nanocrystalline metals, with manipulation of the boundary structure a promising path for tuning this response. In this study, the role of interfacial structural disorder on plasticity and failure of nanocrystalline Cu-Zr alloys ...
2103.04465v2
2021-03-09
The Laser-Diode Heated Floating Zone Method for Automated Optimal Synthesis of Refractory Oxides and Alloys
We perform an experimental investigation of the synthesis of complex materials using the Laser-diode heated floating zone method (L-FZ). We will briefly introduce the Infrared-heated floating zone method of bulk crystal growth and then delve into recent advances in using a Laser-diode heated floating zone method. We de...
2103.05587v1
2021-03-12
Anomalous broadening of specific heat jump at Tc in high-entropy-alloy-type superconductor TrZr2
A high-entropy-alloy-type (HEA-type) superconductor is new category of highly disordered superconductors. Therefore, finding brand-new superconducting characteristics in the HEA-type superconductors would open new avenue to investigate the relationship between structural disorder and superconductivity. Here, we report ...
2103.07217v1
2021-03-15
The importance of overcoming MOVPE surface evolution instabilities for >1.3 $μ$m metamorphic lasers on GaAs
We investigated and demonstrated a 1.3 $\mu$m-band laser grown by metalorganic vapour phase epitaxy (MOVPE) on a specially engineered metamorphic parabolic graded In$_x$Ga$_{1-x}$As buffer and epitaxial structure on a GaAs substrate. Bottom and upper cladding layers were built as a combination of AlInGaAs and InGaP all...
2103.08267v1
2021-03-21
Investigating the electronic origins of the repulsion between substitutional and interstitial solutes in hcp Ti
The high solubility of oxygen in Ti, Zr and Hf makes it difficult to stabilize the protective oxide scales on their surfaces as the subsurface regions can serve as boundless sinks that continuously dissolve oxygen. Alloying elements are crucial to reduce the oxygen solubility and diffusivity within early transition met...
2103.11490v1
2021-03-23
Improvement of local critical current density of REBa2Cu3O7-d by the increase in configurational entropy of mixing at the RE site
REBa2Cu3O7-d (RE123, RE: rare earth) is one of the high-temperature superconductors with a transition temperature (Tc) exceeding 90 K. Because of its high Tc and large critical current density (Jc) under magnetic fields, RE123 superconductors have been expected to play a key role in superconductivity application. To ac...
2103.12261v1
2021-03-23
Chemical requirements for stabilizing type-II Weyl points in MnBi2-xSbxTe4
We show that type-II Weyl point formation in MnBi2-xSbxTe4 is more likely than in MnBi2Te4 when x reaches 0.5, as the alloy case does not suffer from the same degree of lattice parameter sensitivity as in MnBi2Te4. To further substantiate the stability of type-II Weyl points in MnBi2-xSbxTe4, we demonstrate that among ...
2103.12730v2
2021-03-25
Formation of Fractal Dendrites by Laser induced melting of Aluminum Alloys
We report on the fabrication of fractal dendrites by laser induced melting of aluminum alloys. We target boron carbide (B4C) that is one of the most effective radiation-absorbing materials which is characterised by a low coefficient of thermal expansion. Due to the high fragility of B4C crystals we were able to introdu...
2103.13643v1
2021-03-25
Tribochemistry, mechanical alloying, mechanochemistry: what is in a name?
Over the decades, the application of mechanical force to influence chemical reactions has been called by various names: mechanochemistry, tribochemistry, mechanical alloying, to name but a few. The evolution of these terms has largely mirrored the understanding of the field. But what is meant by these terms, why have t...
2103.13836v1
2021-03-31
Slip band interactions and GND latent hardening in a galling resistant stainless steel
Slip activation, slip band interactions, and GND densities in iron-base, galling resistant alloy Nitronic 60 have been characterised at the grain length scale using small-scale mechanical testing with high resolution digital image correlation and high-angular resolution electron backscatter diffraction. By correlating ...
2103.16864v1
2022-02-02
Structural and Magnetic Properties of Fe-Al alloys: an Ab initio Studies
In the framework of density functional theory, the structural and magnetic properties of Fe$_{100-x}$Al$_x$ alloys (${5 \leq x \leq 25}$~at.\%) with the different structural order are investigated. Using the Korringa-Kohn-Rostoker Green's function method with a coherent potential approximation, the equilibrium lattice ...
2202.00978v1
2022-02-02
Nonlinear deformation and elasticity of BCC refractory metals and alloys
Application of isotropic pressure or uniaxial strain alters the elastic properties of materials; sufficiently large strains can drive structural transformations. Linear elasticity describes stability against infinitesimal strains, while nonlinear elasticity describes the response to finite deformations. It was previous...
2202.01055v2
2022-02-19
Atomistic simulations of the deformation behavior of an Nb nanowire embedded in a NiTi shape memory alloy
The influence of pre-strain and temperature on the superior properties exhibited by an Nb nanowire embedded in a NiTi shape memory alloy (SMA) are investigated via molecular dynamics simulations. To this end, a new Nb-Ni-Ti ternary interatomic potential based on the second nearest-neighbor modified embedded-atom method...
2202.09586v1
2022-02-24
Thermodynamics for Nonlinearity under Hidden Structure Information
For substitutional alloys, typically refered to as classical discrete systems under constant composition, we theoretically examine the role of hidden structure information on evolution of nonlinearity (i.e., correspondence between a set of potential energy surface and that of many-body interaction) in canonical ensembl...
2202.11863v1
2022-02-25
Estimation of Grüneisen parameter of high-entropy-alloy-type functional materials
In functional materials like thermoelectric materials and superconductors, the interplay between functionality, electronic structure, and phonon characteristics is one of the key factors to improve functionality and to understand the mechanisms. In the first part of this article, we briefly review investigations on lat...
2202.12516v1
2022-02-25
Alloying Ratio Versus Cluster Size for Reversible Hydrogen Storage in Ni Doped Small Mg Clusters: Dispersion Corrected DFT Study
Dispersion corrected density functional theory ($\omega$B97X-D DFT) method is used to study the molecular hydrogen adsorption in $Ni_nMg_m$ $(1\geq n\geq 3,1\geq m\geq9)$ clusters. All these clusters can effectively adsorb multiple $H_2$ in the preferred binding energy (BE) range between physisorption and chemisorption...
2202.12551v1
2022-03-03
Identification of active slip systems in polycrystals by Slip Trace -- Modified Lattice Rotation Analysis (ST-MLRA)
A simple and versatile strategy, denominated Slip Trace - Modified Lattice Rotation Analysis (ST-MLRA), is presented to enable the identification of the active slip systems in polycrystalline alloys from surface information. The slip plane trace orientation is used to define the potential active slip planes while the a...
2203.01476v1
2022-03-03
First-principles calculations of the surface states of doped and alloyed topological materials via band unfolding method
One of the most remarkable characteristics of topological materials is that they have special surface states, which are determined by the topological properties of their bulk materials. The angle resolved photoemission spectroscopy (ARPES) is a powerful tool to explore the surface states, which allows to further invest...
2203.01569v1
2022-03-21
Thermodynamic descriptors to predict oxide formation in aqueous solutions
We formulate the maximum driving force (MDF) parameter as a descriptor to capture the thermodynamic stability of aqueous surface scale creation over a range of environmental conditions. We use formation free energies, $\Delta_f G$s, sourced from high-throughput density functional theory (DFT) calculations and experimen...
2203.11013v1
2016-03-01
Real-space cluster dynamical mean-field approach to the Falicov-Kimball model: An alloy-analogy approach
It is long known that the best single-site coherent potential approximation (CPA) falls short of describing Anderson localization (AL). Here, we study a binary alloy disorder (or equivalently, a spinless Falicov-Kimball (FK)) model and construct a dominantly analytic cluster extension that treats intra-cluster ($1/d$, ...
1603.00301v4
2016-03-23
Superconductivity of Ta34Nb33Hf8Zr14Ti11 high entropy alloy from first principles calculations
The Korringa-Kohn-Rostoker method with the coherent potental approximation (KKR-CPA) is applied to study the first superconducting high entropy alloy (HEA) Ta34Nb33Hf8Zr14Ti11 (discovered in 2014 with Tc = 7.3 K), focusing on estimations of the electron-phonon coupling constant \lambda. Electronic part of \lambda has b...
1603.07274v1
2016-03-25
Synthesizing Skyrmion Molecules in Fe-Gd Thin Films
We show that properly engineered amorphous Fe-Gd alloy thin films with perpendicular magnetic anisotropy exhibit room-temperature skyrmion molecules, or a pair of like-polarity, opposite-helicity skyrmions. Magnetic mirror symmetry planes present in the stripe phase, instead of chiral exchange, determine the internal s...
1603.07882v2
2016-03-29
Direct Evidence for Suppression of the Kondo Effect due to Pure Spin Current
We study the effect of a pure spin current on the Kondo singlet in a diluted magnetic alloy using non-local lateral spin valve structures with highly spin polarized Co2FeSi electrodes. Temperature dependence of the non-local spin signals shows a sharp reduction with decreasing temperature, followed by a plateau corresp...
1603.08599v1
2016-03-29
Role of Sn impurity on electronic topological transitions in 122 Fe-based superconductors
We show that only a few percentage of Sn doping at the Ba site on BaFe$_2$As$_2$, can cause electronic topological transition, namely, the Lifshitz transition. A hole like d$_{xy}$ band of Fe undergoes electron like transition due to 4\% Sn doping. Lifshitz transition is found in BaFe$_2$As$_2$ system around all the hi...
1603.08772v1
2016-11-30
Nanocrystalline Al-Mg with extreme strength due to grain boundary doping
Nanocrystalline Al-Mg alloys are used to isolate the effect of grain boundary doping on the strength of nanostructured metals. Mg is added during mechanical milling, followed by low homologous temperature annealing treatments to induce segregation without grain growth. Nanocrystalline Al -7 at.% Mg that is annealed for...
1612.00049v2
2016-12-01
Semiconductor, topological semimetal, indirect semimetal, and topological Dirac semimetal phases of Ge$_{1-x}$Sn$_{x}$ alloys
Electronic structures of Ge$_{1-x}$Sn$_{x}$ alloys (0 $\leq$ $x$ $\leq$ 1) are theoretically studied by nonlocal empirical pseudopotential method. For relaxed Ge$_{1-x}$Sn$_{x}$, a topological semimetal is found for $\textit x$ $>$ 41$\%$ with gapless and band inversion at ${\Gamma}$ point, while there is an indirect-d...
1612.00159v2
2016-12-11
Revisiting Jackson-Hunt calculations: Unified theoretical analysis for generic multi-phase growth in a multi-component system
A straight-forward extension of the Jackson-Hunt theory for directionally solidifying multi-phase growth where the number of components exceeds the number of solid phases becomes difficult on account of the absence of the required number of equations to determine the boundary layer compositions ahead of the interface. ...
1612.03376v1
2016-12-20
Fitting of structural parameters to small angle neutron scattering data for nickel-chromium-aluminum alloy in frames of quantum mechanics and classic models of polydispersed spheres
Modified Yukawa's potential is used to fit model parameters of nucleus to the small angle thermal neutron scattering data on the nickel-chromium-aluminum alloy at the transferred momentum $Q$ and effective nucleus radius $R$ production satisfied by condition $Q R \le \hbar$. Analytical polydisperse sphere model is used...
1612.09115v1
2017-02-10
Thermal vacancy formation energies of random solid solutions
Vacancy mechanism plays a dominant role in the atomic migration when a close-packed disordered alloy undergoes ordering transition. However, the calculation of thermal vacancy formation energies (VFEs) of random solid solutions is usually cumbersome due to the difficulty in considering various local atomic environments...
1702.03104v1
2017-02-13
Size-effect of Kondo scattering in point contacts (revisited)
The size-effect of Kondo-scattering in nanometer-sized metallic point contacts is measured with the simplified, mechanically-controlled break-junction technique for CuMn alloy of different Mn concentrations: 0.017; 0.035; and 0.18 ($\pm$0.017) at.\%. The results are compared with our previous publication on nominally 0...
1702.03827v1
2017-02-14
Full Electroresistance Modulation in a Mixed-Phase Metallic Alloy
We report a giant, ~22%, electroresistance modulation for a metallic alloy above room temperature. It is achieved by a small electric field of 2 kV/cm via piezoelectric strain-mediated magnetoelectric coupling and the resulting magnetic phase transition in epitaxial FeRh/BaTiO3 heterostructures. This work presents deta...
1702.04306v1
2017-02-15
Synthesis and Hydrogen Sorption Characteristics of Mechanically Alloyed Mg(NixMn1-x)2 Intermetallics
New ternary Mg-Ni-Mn intermetallics have been successfully synthesized by High Energy Ball Milling (HEBM) and have been studied as possible materials for efficient hydrogen storage applications. The microstructures of the as-cast and milled alloys were characterized by means of X-ray Powder Diffraction (XRD) and Scanni...
1702.04807v1
2017-02-16
Nonequilibrium transport and Electron-Glass effects in thin GexTe films
We report on results of nonequilibrium transport measurements made on thin films of germanium-telluride (Ge_xTe) at cryogenic temperatures. Owing to a rather large deviation from stoichiometry (app. 10% of Ge vacancies), these films exhibit p-type conductivity with carrier-concentration N>10^20cm^(-3) and can be made e...
1702.04876v1
2017-02-27
Intermetallic Nanocrystals: Syntheses and Catalytic Applications
At the forefront of nanochemistry, there exists a research endeavor centered around intermetallic nanocrystals, which are unique in terms of long-range atomic ordering, well-defined stoichiometry, and controlled crystal structure. In contrast to alloy nanocrystals with no atomic ordering, it has been challenging to syn...
1702.08137v2
2017-06-12
Superconductivity and its Enhancement under High Pressure in "F-free" Single Crystals of CeOBiS$_2$
"F-free" CeOBiS$_2$ single crystals have successfully grown, thoroughly eliminating a concern about F-contamination by using a high-purity CsCl flux. The obtained crystals have a plate-like shape with a size of 1.0-3.0 mm in the well-developed plane. Single crystal X-ray structural analysis clearly revealed that the Ce...
1706.03590v1
2017-06-24
Microscopic structure differences in CZTSe quaternary alloys prepared by different techniques revealed by spatially-resolved laser-induced-modification Raman spectroscopy
While producing comparable efficiencies and showing similar properties when probed by conventional techniques, such as Raman, photoluminescence and X-ray diffraction, two thin film solar cell materials with complex structures, such as quaternary compound CZTSe, may in fact differ significantly in their microscopic stru...
1706.08000v1
2017-06-29
Effect of Anodizing Parameters on Corrosion Resistance of Coated Purified Magnesium
Magnesium and its alloys are being considered for biodegradable biomaterials. However, high and uncontrollable corrosion rates have limited the use of magnesium and its alloys in biological environments. In this research, high purified magnesium (HP-Mg) was coated with stearic acid in order to improve the corrosion res...
1706.09547v1
2017-10-04
Tracking a hysteretic and disorder-broadened phase transition via the electromagnon response in improper ferroelectrics
We demonstrate that electromagnons can be used to directly probe the nature of a phase transition between magnetically ordered phases in an improper ferroelectric. The antiferromagnetic/paraelectric to antiferromagnetic/ferroelectric phase transition in Cu$_{1-x}$Zn$_{x}$O ($x=0, 0.05$) alloys was tracked via the elect...
1710.01573v1
2017-10-13
Atomic force microscopy of transformation toughening in ceria-stabilized zirconia
We demonstrate in this paper that atomic force microscopy can be successfully used to gain further insights into the understanding of transformation toughening in ceria stabilized zirconia. Transformation was induced by stresses accumulated in the region surrounding propagating cracks in double torsion samples. The res...
1710.04918v1
2017-10-19
The Structural Origin of Enhanced Dynamics at the Surface of a Glassy Alloy
The enhancement of mobility at the surface of an amorphous alloy is studied using a combination of molecular dynamic simulations and normal mode analysis of the non-uniform distribution of Debye-Waller factors. The increased mobility at the surface is found to be associated with the appearance of Arrhenius temperature ...
1710.06976v1