ABSTRACT For modern engineering applications, the prediction of residual stresses is a starting-point for the subsequent optimisation of the design with regard to the process induced stresses on the macro and the grain scale. In this paper, a new approach for the numerically efficient prediction of phase-specific residual stresses (residual stresses of second kind) in two-phase materials is presented

ABSTRACT A dislocation assisted self-consistent model based on Tandon and Weng approach and Bergstrom dynamic recovery model for particulate-reinforced composites has been extended to consider the matrix evolution during high-temperature deformation on flow stress. The impact of main influential processing parameters such as temperature, strain, and strain rate in addition to reinforcement characteristics

ABSTRACT The superstructure and basic structure of ternary Yb-Cd-Mg 1/1 quasicrystal approximants with the compositions Yb 12.9 Cd 78.4 Mg 8.8 and Yb 13.3 Cd 64.2 Mg 22.5 were investigated using X-ray structural analysis. The former was determined to have a face-centred packing structure comprising two distinguishable Tsai-type rhombic triacontahedron clusters (space group F d 3 ¯ , a = 31.377 ( 1

ABSTRACT The present work describes the effect of Ni/Fe ratio on microstructure, tensile flow and work hardening behaviour of tungsten heavy alloys (WHAs) based on 92 wt. % W with varying Ni/Fe ratios in heat treated and swaged conditions. Evaluation of properties in the heat treated and swaged conditions reflect that the increasing Ni/Fe ratio has resulted in the enhancement of tensile as well as

ABSTRACT In this study, Ni2-x Co x MnSb full-Heusler alloys (1.00 ≤ x ≤ 1.75) were prepared by arc melting process, and examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and SQUID. The L21 crystal structure of the synthesised Heusler alloy was confirmed by XRD patterns, and it was observed that the use of Co instead of Ni caused a decrease in the interatomic distance. The magnetisation

ABSTRACT Hot extrusion (HEX) and isothermal forging (ITF) are two critical processing methods in manufacturing of Ni-based powder metallurgy (P/M) superalloys. Hot compressions with different parameters were performed on a novel Ni-based P/M superalloy in as-extruded condition to simulate ITF and the related microstructure evolution. The results revealed that the as-extruded alloy was fully recrystallised

ABSTRACT In the studies related to thermodynamic and structural functions of liquid alloys at high temperatures using linear temperature-dependent interaction parameters, in some cases, artificial miscibility gaps or artefacts are noticed. These artificial miscibility gaps in these functions at higher temperatures are usually asymmetric with respect to the concentration. The presence of the artificial

ABSTRACT The effect of transition elements, specifically Mn, Cr, V, and Mo, on dispersoid formation and mechanical properties in 6082 aluminum alloy was studied. The elevated-temperature mechanical properties were evaluated based on the compressive yield strength and creep resistance. The results indicated that the addition of Mn to the 6082 alloy resulted in the formation of a large number of the

ABSTRACT Despite a large body of literature, mechanisms contributing to low temperature jerky flow remain controversial. Here, we report a cross-over from a smooth at room and liquid nitrogen temperatures to serrated plastic flow at 4.2 K in high-entropy CrMnFeCoNi alloy. Several complimentary investigations have been carried out to get a coherent physical picture of low temperature jerky flow in these

In this study, we present a detailed theoretical investigation of the effect of an externally applied magnetic field on the energy states 1 s , 1 p , 1 d and 1 f in the spherical quantum dot with finite and infinite confinement potentials. For both finite and infinite spherical quantum dot, the first four electron energies, Zeeman transition energies between these electronic states and optical absorption

The influence of the volume fraction of nano-sized TiCN reinforcement additive on the mechanical properties and the microstructure of Al-based composite was studied. It was found that the addition of nano-sized TiCN particulates into the Al-matrix leads to a substantial improvement of the mechanical properties of the composite, TiCN-Al. However, the obtained results showed that the strengthening effect

Material failure by white-etching-cracks (WECs) can cause enormous economic costs. The formation of WECs emerges from the decomposition of the original, usually cementite-containing, microstructure. As small amounts of electric current can trigger this failure mechanism, we investigate the contribution of electric current to cementite decomposition. We applied ∼700 A/cm2 for two weeks at 60°C to a

(2020). XV International Workshop on Complex systems Andalo (Trento) Italy. 17–20 March 2019. Philosophical Magazine: Vol. 100, Andalo special Issue on Complex systems, pp. 2543-2543.

We discuss the role of non-hydrodynamic processes in viscoelastic transition in pure liquids. In particular, using both analytical results and molecular dynamics simulations, we clarify the effect of the shear stress relaxation on the transverse dynamics. We use as an example the Lennard-Jones fluids. We analyse the frequency dependence of the shear modulus and its connection to the non-hydrodynamic

(2020). Publisher’s Note. Philosophical Magazine: Vol. 100, Andalo special Issue on Complex systems, pp. 2658-2658.

In this paper, the austenite grain growth behaviour of 12Cr ultra-super-critical (USC) rotor steel was investigated by a series of heat treatments. The heat treatments at heating temperatures of 900°C–1250°C and holding time of 1 h–20 h were conducted in an electric box-type heating furnace. Experimental results showed that the sizes of austenite grain were affected by heating temperatures and holding

I comparatively determine the structural and electronic properties of Li2FePO4F compounds with F substituted by Cl, Br and I atom using the spin density functional theory with Perdew–Burke–Ernzerhof generalised gradient approximation (GGA + U). The lattice parameters and volumes are improved by the dopants because of the greater atomic radius in dopants. Non-metal doping in Li2FePO4F reduces the band

We use nanoindentation to perform elastic cycling on, and to characterise, the bulk metallic glass Cu46Zr46Al7Gd1. From multiple loading curves, cumulative distributions are determined for several properties, including the initial yield load, the hardness and the indentation modulus. The distributions are characterised by the median property value and by their width. The effects of elastic cycling

(2020). Correction. Philosophical Magazine: Vol. 100, No. 19, pp. 2540-2541.

In the paper, molecular dynamics simulation is applied to study the evolution and distribution of subsurface defects during nanoscale machining process of single-crystal copper. The chip-removal mechanism and the machined-surface-generative mechanism are examined through analysis of the dislocation evolution and atomic migration of the workpieces. The findings show that under different stresses and

Electronic, optical and magnetic properties of perovskite oxides PrXO3(X = V, Cr) are calculated by first-principle calculations. The calculations of electronic band structure and density of states (DOS) show that the PrVO3 exhibits metallic behaviour, while PrCrO3 exhibits half-metallic nature with direct band gap. The calculated band gap of PrCrO3 is 2.7 in the minority spin state. The origin and

Structural heritage between bulk metallic glasses (BMGs) and their relevant crystals has already been acknowledged. But how this kind of heritage is represented is still unclear. In the present paper, firstly, two important characters are considered to determine the principal cluster of crystal, i.e. the atomic-packing efficiency which is evaluated by atomic density radial distribution method and cluster

Traditionally, for hard materials, two types of straight disclinations are identified although some Somigliana disclinations with different aspects have been treated theoretically. Here, we consider four physically distinct types of curved generalised disclinations, one of which reduces to two straight types, giving a total of five. We indicate typical applications for the different types.

Orientation rotation tendency with respect to target orientation in body-centred cubic (bcc) crystal is investigated under different rolling modes. Oriented stability is proposed to describe the rotation rate towards target orientation in contrast to conventional orientation stability. The oriented stability distribution in Euler space can clearly present how an orientation contributes to target orientation

ABSTRACT In the aluminum industry, the needs of predictability of the kinetics of precipitation during the artificial aging processes increase as the targeted applications require the maximisation of properties at the lowest costs possible. In this regard, kinetics modelling can be helpful to design the heat treatment processes. Despite using many fitting parameters, available models show a lack of

Low-energy dislocation structure is one classical self-organised dislocation pattern, among which persistent slip band (PSB) ladders is the most representative. Periodically distributed PSB ladders consist of two phases: matrix phase and pattern phase. In the new two-phase model, the appearance of pattern phase results in the softening of PSBs with lower elastic constant. The formation of PSB ladders

For modern engineering applications, the prediction of residual stresses is a starting-point for the subsequent optimisation of the design with regard to the process induced stresses on the macro and the grain scale. In this paper, a new approach for the numerically efficient prediction of phase-specific residual stresses (residual stresses of second kind) in two-phase materials is presented. The proposed

Molecular Dynamics (MD) simulations were used to investigate the mechanical response and interfacial mixing of Al/Fe system loaded in uniaxial compression at a constant strain rate of 5 × 107s−1 and five temperatures (150, 300, 500, 700, and 900 K). During the simulations, the temperature was kept below the melting temperature of aluminium (∼933 K) so that stress assisted solid-state mixing is examined

Micro-pillars of solution-treated and aged AZ91 magnesium alloy (Mg-9Al-0.7Zn-0.2Mn) have been used to study the influence of precipitates on plastic deformation mechanisms. The micro-pillars were compressed along [ 55 10 ¯ 9 ] and [ 01 1 ¯ 0 ] directions in order to activate basal slip and { 01 1 ¯ 2 } twinning, respectively. The critical resolved shear stresses were determined. Precipitates had limited

The evolution processes of the defects in Ni, Ni-Cr and Ni-Mo alloys under 400 keV Ne ion irradiation at different temperatures were investigated. At room temperature, the defect sizes are between 2 and 4 nm and defect densities are in the range of 1.24 × 1015–1.39 × 1015 m−2. With increasing irradiation temperature, the defect sizes become larger, and the defect densities decrease. Moreover, under

The mechanical, electrical, optical and thermoelectric properties of SrS graphene-like structure are discussed using the density functional theory and FP-Lapw method. To calculate the electrical properties, the generalized gradient approximation, Kohn–Sham, and Green function Waves function approximations are used in our correlation potential, and the optical calculations are performed based on the

The electrical resistivity and the thermoelectric power of liquid metal Cs have been theoretically investigated using the muffin-tin potential approach with the help of an accurate experimentally measured structure factor, S(q), and radial distribution function, g(r) measured along the liquid–vapour coexistence curve. Our procedure provides a clear evidence of the existence of metal–non-metal transition

We show how the combination of the spatial autocorrelation function and permeability calculations, applied to 3D X-ray computed tomography data, can yield quantitative information on the anisotropy of both meso-structure and fluid flow in Diesel Particulate Filter (DPF) materials, such as Cordierite and SiC. It was found that both the degree of anisotropy, and the orientation of the permeability and

ABSTRACT We show how the combination of the spatial autocorrelation function and permeability calculations, applied to 3D X-ray computed tomography data, can yield quantitative information on the anisotropy of both meso-structure and fluid flow in Diesel Particulate Filter (DPF) materials, such as Cordierite and SiC. It was found that both the degree of anisotropy, and the orientation of the permeability

The microstructure of an Al-Cu-Li alloy sheet is characterised in the solution treated, underaged, and peak aged tempers. Its mechanical response under uniaxial tension is measured at 90 K , 173 K , and 300 K along 0 ∘ , 45 ∘ , and 90 ∘ to the rolling direction. The anisotropic stress-strain curves are interpreted using a polycrystal plasticity model, which implements three hardening modes suggested

We have studied the doping concentration dependence of the thermoelectric (TE) properties for the n- and p-doped CaIn2P2 layered Zintl phase at two fixed temperatures: T = 600 and 900 K through first-principles electronic band structure calculations combined with Boltzmann's transport theory within charge-carrier relaxation time and rigid band approximations. The band structure calculated using the

Analysis of the surface quantum states in quasi-two dimensional organic conductors induced by an external magnetic field is carried out within the quasi-classical approximation. In a magnetic field parallel to the surface along the y direction, these states result from the electronic transitions between the small closed orbits in the vicinity of the Fermi surface which are extremal cross-sections of

We report on ab-initio all electrons spin-polarised density-functional calculations for the band structure, optical spectra and magnetisation of bulk MnAs with NiAs-type lattice structure with emphasis on their dependence on pressure. The aim of this contribution is to show how the investigated properties behave upon compression. Our findings are compared when possible with those reported in the literature

ABSTRACT Recently, previous studies have shown that at room temperature, EuNbO3 adopts an orthorhombic structure of Imma space group with a ferromagnetic behaviour. The relevant idea of ⁣this work is to provide a new insight into some electronic and magnetic behaviours of EuNbO3 in orthorhombic structure, which are still unknown, based on the results already found previously. The structural properties

The influences of chemical disorder and external loading conditions on the reversible structural transformation between hexagonal close-packed (HCP) and face centred cubic (FCC) phases in CrCoFeNi high entropy alloys (HEAs) are studied from first-principles calculations. The generalised planar fault energy curves are utilised to analyse the competition between the transformation and deformation twining

ABSTRACT The influences of chemical disorder and external loading conditions on the reversible structural transformation between hexagonal close-packed (HCP) and face centred cubic (FCC) phases in CrCoFeNi high entropy alloys (HEAs) are studied from first-principles calculations. The generalised planar fault energy curves are utilised to analyse the competition between the transformation and deformation

ABSTRACT In this current paper, we purpose a ferrielectric mixed (7/2;2) spins Ising model to describe the dendrimer superlattice using Monte Carlo study (MCs). The ground state phase diagrams of dendrimer superlattice with half and integer mixed spins in (DS, EZ ), (JσS, EZ ) and (JσS, DS ) planes (DS (or σ): crystal field and Ez : Electric field) were obtained. Typical temperature dependences of

The transfer of plastic sliding through a crystalline interface involves at least a dislocation having a branch in each crystal. The elastic field associated with this elemental configuration has been processed in the past by Belov et al. (1983 A.Y.Belov, A.Chamrov, V.L.Indenbom and J.Lothe , Elastic fields of dislocations piercing the interface of an anisotropic bicrystal , Phys. Stat. Sol. (B) 119

The evolution of deformation texture and microstructure in commercially pure Al (cp-Al) and two Al–Mg alloys (Al–4Mg and Al–6Mg) during cold rolling to a very large strain (true strain εt  ≈ 3.9) was investigated. The development of deformation texture in cp-Al, after rolling, can be considered as pure metal or Copper-type, which is characterised mainly by the presence of Cu {112}<111>, Bs {110}<112>

ABSTRACT We present a fast algorithm for generating Laguerre diagrams with cells of given volumes, which can be used for creating RVEs of polycrystalline materials for computational homogenisation, or for fitting Laguerre diagrams to EBSD or XRD measurements of metals. Given a list of desired cell volumes, we solve a convex optimisation problem to find a Laguerre diagram with cells of these volumes

ABSTRACT We use a state-of-the-art, ultrafast camera to probe the nanosecond pulse laser ablation of a metallic glass target in water. The laser-induced plasma of metallic glass is captured for the first time. We further observe a series of shock waves in water and the cavitation bubble on the target surface. The shock waves inherit the rapid expansion of the plasma, satisfying the momentum conservation

ABSTRACT In this work, the structural, electronic, and dynamical properties of novel half-Heusler (HH) alloy AlNiP are studied by applying first-principles density functional theory (DFT). The structural properties of AlNiP in the LiAlSi-type crystal structure with three different phases (α-phase, β-phase, and γ-phase) in different atomic arrangements are explored. The ‘γ-phase’ of AlNiP is found to

ABSTRACT The spin Hamiltonian parameters (SHPs), local structure and their composition dependences for impurity V4+ in xBaCl2-(30–x)BaO-68B2O3-2V2O5 (x = 0, 2, 5, 10 mol%) glasses are theoretically analyzed by using the perturbation formulae of SHPs for octahedral 3d1 clusters with tetragonal compression. The power law composition functions for the relevant quantities (covalency factor N, relative

ABSTRACT In this work, a theoretical and experimental study has been carried out with the eutectic Al12.6Si alloy (wt.%) in order to determine and evaluate the transient heat flow parameters, such as metal/mold interfacial heat transfer coefficient (hi), growth and cooling rates (VL and TR, respectively), during upward solidification. The experimental thermal data were obtained via temperature mapping

The thermodynamics of hydride formation is one of the most important properties of the metal-hydrogen system, and states its potential for further uptake. For this reason, much research is focused on the use of first principle calculations as a predictive tool in the study of hydride stability. In this paper, First-principles density functional calculations were performed to predict the effect of co-substitution

ABSTRACT The spinel oxides SnV2O4 and SnCr2O4 are analysed to reveal the mechanical, electronic and magnetic properties using Wien2k software. The negative formation energy and positive elastic constants shows the studied materials are thermodynamically and mechanically favorable. In ferromagnetic (FM) state more energy release than antiferromagnetic (AFM) state. The above room temperature magnetism

Since 1998 the primitive relaxation time τ 0(T,P) of the Coupling Model (CM) and the Johari-Goldstein (JG) β-relaxation time τJG (T,P) are shown approximately equal in many glass-formers. The CM relation between τ 0(T,P) and τα (T,P) at any T and P is exact. Additionally from the CM relation τα (T,P)/τ 0(T,P) is exactly invariant to variations of T and P while τα (T,P) is kept constant, and τ 0 is

In this work, numerical computations of image forces and stored energy during the growth of a strain free grain within a recovered matrix containing an array of identical dislocations are performed. A decrease of the stored energy is observed when image forces are attractive and an increase when image forces are repulsive. The variation of elastic energy depends closely on the material elastic anisotropy

Based on the full-potential linearised augmented plane wave plus local orbitals (FP-L/APW + lo) method within the density functional theory (DFT), the structural, electronic, and magnetic calculations of the cubic oxide perovskite NdInO3 compound have been done under the generalised gradient approximation (GGA). The exchange and correlation (XC) potential is defined as GGA framework in the analyses

The states of a single dopant centre in zinc-blende GaN-based conical quantum dots with spherical cap are theoretically investigated by analytically solving the corresponding effective mass equation taking advantage of the localisation of the ionised impurity at the cone apex. Nonlinear optical response is analysed through the calculation of the coefficients of optical absorption, relative refractive

The thermodynamic and surface properties of the ternary Al–Cu–Fe alloy in the liquid state have been computed using different models. The thermodynamic properties, such as activity and excess free energy of mixing and the surface properties, such as surface tension have been calculated. The temperature dependence of activity and surface concentration of the components of the ternary Al–Cu–Fe alloy

In this paper, we perform molecular dynamics simulations of a dielectric fluidic material composed of permanent molecular dipoles. The dielectric spectrum features two peaks at lower frequencies than the system phonon frequency. The primary peak is observed at all temperatures studied and shifts toward lower frequencies as the temperature decreases. During this shift, the secondary peak emerges with

ABSTRACT Ab initio pseudopotential calculations have been conducted for the superconducting filled skutterudite compounds BaPt 4 Ge 12 , SrPt 4 Ge 12 , and ThPt 4 Ge 12 in order to explore the effect of spin–orbit interaction(SOI) by using the planewave pseudopotential method and the density functional theory. The electronic structure calculations suggest that the density of states at the Fermi level

Grain boundaries of metallic materials subjected to severe plastic deformation exhibit significantly enhanced diffusivity and excess energy compared with their relaxed poly- or bi-crystalline counterparts even when the macroscopic degrees of freedom are the same in both types of grain boundaries. Boundaries of excess energy are/can be relaxed by annealing. As a first step in accounting for this experimentally

ABSTRACT In this present report, we have extensively forecasted thermodynamic, magneto-electronic and structural properties of new Co-based full-Heuslers with the help of density functional theory. The stable ground state and cohesive energy approve the stability in Fm-3 m ferromagnetic phase possessing a direct forbidden bandgap within mBJ functional. Band profile and density of states define half-metallic