Publications de William Curtin

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Random alloys are multicomponent systems where the atomic type on each lattice site is independent of the atom types on any other lattice site. The fluctuations in local atomic configurations inherent to the random alloy prevents the accurate application o ...

Pure Mg has low ductility due to a transition of < c+a > pyramidal dislocations to a sessile basal-oriented structure. Dilute alloying generally improves ductility. Enhancement of pyramidal cross-slip from the lower-energy pyramidal II plane to the higher- ...

Yielding in pure BCC metals and dilute substitutional alloys occurs by double-kink nucleation and propagation along screw dislocations. At low temperatures, the yield stress is controlled by double-kink nucleation. Here, an analytical statistical model is ...

Magnesium has multiple dislocation and twinning systems with starkly different properties, which make its plastic deformation strongly anisotropic and highly complex. Existing empirical interatomic potentials fail to capture the full scope of these propert ...

Age hardening induced by the formation of (semi)-coherent precipitate phases is crucial for the processing and final properties of the widely used Al-6000 alloys. Early stages of precipitation are particularly important from the fundamental and technologic ...

High Entropy Alloys (HEAs) are a new broad class of near-random solid solution alloys that can possess some impressive mechanical and physical properties including high stability against grain growth (i.e. low grain boundary (GB) mobility). Here, it is sho ...

Experiments on the intrinsic stress in immiscible Cu/W nanomultilayers (NMLs) show two unusual features: a compressive-to-tensile transition as a function of NML deposition conditions and extremely high interface stresses under both high- and low-pressure ...

The total energy of an atomistic dislocation includes contributions from the inelastic/large-distortion 'core' region. Capturing this inelastic 'core' energy is important, especially for dislocations with a curvature in the 10–100 nm scale. Current impleme ...

The finite-temperature yield stress of Mg-Al alloys undergoing basal slip is investigated using a recently developed parameter-free solute strengthening model. The model takes input from first-principles calculations of the dislocation/solute interaction e ...

High-strengthmetal alloys achieve their performance via careful control of the nucleation, growth, and kinetics of precipitation. Alloy mechanical properties are then controlled by atomic scale phenomena such as shearing of the precipitates by dislocations ...

Improvement of single wall carbon nanotube (CNT) bundle mechanical properties through carbon ion irradiation is investigated using molecular dynamics. Increased inter-tube shear and toughness properties through formation of inter-tube cross-links is balanc ...

The element Vanadium (V) appears unique among alloying elements for providing high strengthening in both the fcc Co-Cr-Fe-Mn-Ni-V and bcc Cr-Mo-Nb-Ta-V-W-Hf-Ti-Zr high-entropy alloy families. The origin of Vanadium's special role is its atomic volume: larg ...

Recent data on the Noble metal (Pd-Pt-Rh-Ir-Au-Ag-Cu-Ni) high entropy alloys (HEAs) shows some of these materials to have impressive mechanical properties. Here, a mechanistic theory for the temperature-, composition-, and strain-rate-dependence of the ini ...

Mo-Ti alloys form solid solutions over a wide range of compositions, with lattice misfit parameters increasing significantly with titanium content. This indicates a strong increase in the critical stress for edge dislocation motion. Here, we probe the tran ...

Metals are known to exhibit mechanical behaviour at the nanoscale different to bulk samples. This transition typically initiates at the micrometre scale, yet existing techniques to produce micrometre-sized samples often introduce artefacts that can influen ...

An average-atom (A-atom) embedded-atom-method potential for random multicomponent alloys at any composition is derived analytically and validated by comparing A-atom and true random alloys bulk and defect properties, in model Fe-Ni-Cr systems. The A-atom c ...

IMPACT STATEMENT Experiments and theory are highlighting chemical ordering in high-entropy alloys (HEAs) as important for mechanical properties but the high strength in CoCrFeNiPd is predicted here to be achievable in the random alloy due to the large misf ...

The competition between dislocation emission and cleavage at a crack tip plays an important role in governing the intrinsic fracture behavior of crystalline materials. This competition is not well understood in magnesium, which has many different combinati ...

Energy efficiency is motivating the search for new high-temperature (high-T) metals. Some new body-centered-cubic (BCC) random multicomponent "high-entropy alloys (HEAs)" based on refractory elements (Cr-Mo-Nb-Ta-V-W-Hf-Ti-Zr) possess exceptional strengths ...

The core structures of < c + a > edge and screw dislocations in Mg are computed using density functional theory (DFT). Both types dissociate into two 1/2 < c + a > partials on the second-order pyramidal planes. These DFT results are then allowed to relax w ...

William Curtin

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Atomistic-continuum coupling of random alloys

Design of Ductile Rare-Earth-Free Magnesium Alloys

Theory of double-kink nucleation in dilute BCC alloys

Magnesium interatomic potential for simulating plasticity and fracture phenomena

Ab initio Modelling of the Early Stages of Precipitation in Al-6000 Alloys

Theory of spontaneous grain boundary roughening in high entropy alloys

Origin of interface stress enhancement and compressive-to-tensile stress transition in immiscible nanomultilayers

Atomistic dislocation core energies and calibration of non-singular discrete dislocation dynamics

First-principles prediction of yield stress for basal slip in Mg-Al alloys

Machine learning for metallurgy III: A neural network potential for Al-Mg-Si

A theoretical quantification of the possible improvement in the mechanical properties of carbon nanotube bundles by carbon ion irradiation

Vanadium is an optimal element for strengthening in both fcc and bcc high-entropy alloys

Predicting yield strengths of noble metal high entropy alloys

The influence of lattice misfit on screw and edge dislocation-controlled solid solution strengthening in Mo-Ti alloys

Cast aluminium single crystals cross the threshold from bulk to size-dependent stochastic plasticity

Average-atom interatomic potential for random alloys

Origin of high strength in the CoCrFeNiPd high-entropy alloy

Brittle and ductile crack-tip behavior in magnesium

Strength can be controlled by edge dislocations in refractory high-entropy alloys

First-principles core structures of < c+a > edge and screw dislocations in Mg