From the Maxwell’s Equations of Lattice Deformations to the Description of the Universe by a « Crystalline Ether »

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Metastable β-Ti alloys exhibiting transformation-induced plasticity (TRIP) + twinning-induced plasticity (TWIP) generally achieve a good combination of ultimate strength and ductility. However, these alloys often suffer from low yield strength and exhausted hardening capability at later strains due to poor sequential regulation of the TRIP and TWIP effects. Here, we report a TRIP + TWIP metastable β Ti, Ti-9.2Mo-2Al-2Fe (wt. %), exhibiting high yield/ultimate stress of ∼750/1200 MPa and large elongation of

The electronic density of states (DOS) is a fundamental property in materials science that quantifies the distribution of available electronic states. The DOS is a particularly useful descriptor for materials discovery as it underlies many properties of a material, such as its conductivity, band gap or electronic heat capacity. However, the computation of the DOS through quantum mechanical calculations is costly, hindering its applicability for large systems typically encountered in materials discovery. Mac

Three-dimensional (3D) rhombic zero-depth pores present a promising solution to the challenges associated with the requirement for ultrathin membranes in DNA sequencing. This study provides a comprehensive numerical analysis of 3D rhombic zero-depth pores formed at the intersection of triangular microchannels using finite element modeling. The model was validated with a mean absolute error of 2.75% between numerical and experimental results. We identified a critical channel length, beyond which pore conduct

Frequency metrology lies at the heart of precision measurement. Optical frequency combs provide a coherent link uniting the microwave and optical domains in the electromagnetic spectrum, with profound implications in timekeeping, sensing and spectroscopy, fundamental physics tests, exoplanet searches, and light detection and ranging. Here, we extend this frequency link to free electrons by coherent modulation of the electron phase by a continuous-wave laser locked to a fully stabilized optical frequency com

The energy geostructures are an innovative multifunctional technology that couples their structural support with the heating/cooling role of heat exchangers. The heating/cooling operations of such technology lead to thermo-hydro-mechanical interaction between the structure and the surrounding elements such as the soil and the groundwater. The temperature change in the geostructure can be uniform or non-uniform, leading respectively to thermally induce axial strain and curvature. The first aspect has been we

The utilization of subwavelength resonators, such as small electric dipoles, plasmonic resonators, or objects made of materials with a high dielectric constant, has enabled the manipulation of electromagnetic fields down to the subwavelength regime with synthetic electromagnetic materials built from dense arrangements of such resonant inclusions [1]. Guiding [2] and focusing [3] of electromagnetic energy at the deep subwavelength scale has been demonstrated for electromagnetic waves in metamaterials, by exp

Tribological problems are particularly difficult to comprehend. Different physical mechanisms (including the environment, plastic deformation, third body interactions, phase transformations, recrystallization) interact at disparate length and time scales. Here, we will present some of our recent attempts to understand the origins of wear mechanism at the atomistic level. Macroscopically, the wear process, in terms of debris formation, is well described by the well-known Archard model [1]. As suggested, the

Multiferroics are materials in which ferroelectric and magnetic e.g., ferromagnetic or antiferromagnetic orders co-exist. Some of these show the magnetoelectric effect which is the coupling between electric and magnetic degrees of freedom leading to induction of electric polarization by an applied magnetic field and also induction of magnetic polarization by an applied electric field. Multiferroic substances have attracted attention in recent times as they are expected to show relatively larger magnetoelect

Architectures depict design principles, paradigms that can be understood by all, allow thinking on a higher plane and avoiding low-level mistakes. They provide means for ensuring correctness by construction by enforcing global properties characterizing the coordination between components. An architecture can be considered as an operator A that, applied to a set of components B, builds a composite component A(B) meeting a characteristic property P. A theory of architectures must address several fundamental q

The mechanical action on iron of the first horseshoe electro-magnets (1824) was obvious. They quickly found important applications (telegraphy). Their use to investigate more subtle magnetic, magneto-optical, atomic or nuclear properties of matter began in 1845 with Faraday. Until the 1970s, when superconducting magnets became common, iron-cored electromagnets were normally used to produce steady magnetic fields of high intensity. We will follow the history of a series of fundamental physics discoveries, of

The purpose of this research project is to develop variational integrators synchronous or asynchronous, which can be used as tools to study complex structures composed of plates and beams subjected to large deformations and stress. We consider the geometrically exact models of beam and plate, whose configuration spaces are Lie groups. These models are suitable for modeling objects subjected to large deformations, where the stored energy chosen is adapted for the types of materials used in our field (isotrop

The applicability of extremely thin non-electroneutral membranes for ion-selective electrodes (ISEs) is investigated. A theoretical treatment of potential and concentration profiles in space-charge membranes of

In high-speed dry milling of thin-walled parts, the cutter-workpiece temperature rises asymptotically with cutting speed, causing excessive cutter tooth wear and workpiece thermal expansion, which in turn reduces the cutter life and produces dimensional and geometrical variabilities in the machined part. Therefore, a basic understanding of the thermal aspect of machining and the effecting parameters is essential for achieving better part quality with improved productivity. This paper presents a transient mi

A detailed study of the strain-hardening on a Fe-9Cr-0.1C tempered martensitic model alloy has been undertaken in the temperature range of 77-343 K. The true stress-true strain curves were calculated from tensile test data. In the framework of a phenomenological model for the strain- hardening based on dislocation mechanics, it has been shown that, above 170 K, the whole post-yield behavior can be reasonably described by a single law. On the contrary, below 170 K, a careful examination of the strain-hardeni

We propose a definition for the dipole of an individual molecule in a molecular solid or fluid. This problem is currently dealt with by partitioning-according to some prescription-the continuous electron density of the condensed phase. Instead, here we focus directly on the coupling of externally applied electric fields to the molecular motion. Our concept of dipole is therefore based on experimentally accessible quantities, such as the infrared spectra and, more generally, the low-frequency dielectric prop

The present workshop dealt both theoretically and experimentally with issues of primary damage and irradiation induced defect evolution, helium and other impurities, dislocation-defect interactions, deformation to large plastic strains and fracture. It was focused on the bcc structure (Fe, V and their alloys), but a number of presentations and discussions were centred around results in the fcc and hcp structures. (C) 2003 Elsevier B.V. All rights reserved.

The paper presents experimental results obtained as part of the GEMCAR European project using the VERIFY EMP simulator belonging to the Swiss Defense Procurement Agency (Spiez). VERIFY generates a vertically polarized electric field with a rise time of 0.9 ns and an FWHM of 24 ns. The working volume is 4×4×2.5 m3 and the maximum E-field amplitude is 100 kV/m. Two experimental models for the vehicle and the cable harness were used for the tests. Measurements of electric and magnetic fi

In this paper, an analysis of electric and magnetic fields radiated by lightning first and subsequent return strokes to tall towers is presented. The contributions of the various components of the fields, namely, static, induction, and radiation for the electric field, and induction and radiation for the magnetic field are illustrated and discussed. It is shown in particular that the presence of a tower tends, in general, to increase substantially the electric and magnetic field peaks and their derivatives.

The deformed microstructures of both irradiated and unirradiated Fe-9%Cr (Fe-9Cr) uniaxial tensile specimens have been examined to identify controlling mechanisms. Deformation following irradiation is found to occur in poorly defined channels about 100 nm wide, causing formation of discrete steps at surfaces and, interestingly, designated by nonuniformly distributed highly elongated voids. Deformation is by motion of a(0)/2 dislocations, which interact with and decompose irradiation-induced a(0)

Structural dynamics in semi-quantum and quantum solids (Ne, H2 and D2) is reported, and compared to results in classical solids such as Ar. The structural dynamics is driven by excitation of the lowest Rydberg state of the NO impurity. The resulting charge redistribution induces a local radial deformation of the medium ('bubble' formation) around the impurity. The steady-=state spectroscopic signatures of this process are presented and analyzed in the configuration coordinate model and harmonic approxn. Int

From the Maxwell’s Equations of Lattice Deformations to the Description of the Universe by a « Crystalline Ether »

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Preserving high work hardening without sacrificing yield strength in a metastable β Ti alloy via relay-like hardening mechanism

Towards a Universal Model for the Electronic Density of States

Numerical characterization of electrochemical transport in three-dimensional rhombic zero-depth pores

Unifying frequency metrology across microwave, optical, and free-electron domains

Thermo-mechanical behaviour of energy geostructures subjected to bending thermal actions

Non-Reciprocal and Topological Wave Phenomena at the Sub-Wavelength Scale

Wear at the asperity level: An atomistic viewpoint

AC Magnetoelectrical Susceptibility Study of Multiferroics

Architectures: Design patterns for component-based systems

Physics in magnetic fields from Michael Faraday to Pierre Weiss & his contemporaries

Lie group and Lie algebra variational integrators for flexible beam and plate in R3

Theoretical treatment and numerical simulation of potential and concentration profiles in extremely thin non-electroneutral membranes used for ion-selective electrodes

FEM-based prediction of workpiece transient temperature distribution and deformations during milling

Tensile properties of a tempered martensitic iron-chromium- carbon model alloy

Dynamical monopoles and dipoles in a condensed molecular system: The case of liquid water

Second IEA fusion materials agreement workshop on modeling and experimental validation

Electromagnetic field interaction with vehicle cable harness: an experimental analysis

Current and electromagnetic field associated with lightning-return strokes to tall towers

Post-irradiation deformation in a Fe-9%Cr alloy

Structural dynamics in quantum solids