Publications de William Curtin

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

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 ...

2025

Efficient atomistic/continuum coupling using lattice Green's functions

William Curtin

A/C coupling involves two boundaries: (a) an inner boundary that connects the atomistic and continuum domain and (b) an outer boundary where displacement or force boundary conditions are applied. Here, the lattice Green's function (LGF)–based flexible boun ...

2024

Solute-strengthening in metal alloys with short-range order

William Curtin, Shankha Nag

Recent surging interest in strengthening of High Entropy Alloys (HEAs) with possible chemical ordering motivates the development of new theory. Here, an existing theory for random alloys that accounts for solute-dislocation and solute–solute interactions i ...

2024

Strengthening by {110} and {112} edge dislocations in BCC high entropy alloys

William Curtin

Mechanical tests and microscopy studies on body-centered cubic (BCC) high entropy alloys reveal transitions from screw to edge dislocation slip and from {110} to {112} slip plane activity. Here, a strengthening theory for BCC edge dislocation slip on {112} ...

2024

Neural network potential for Zr-H

William Curtin, Pandula Manura Liyanage

The introduction of Hydrogen (H) into Zirconium (Zr) influences many mechanical properties, especially due to low H solubility and easy formation of Zirconium hydride phases. Understanding the various effects of H requires studies with atomistic resolution ...

Elsevier2024

Strengthening of edge prism dislocations in Mg-Zn by cross-core diffusion

William Curtin

The activation of prismatic slip in Mg and its alloys can be beneficial for deformation and forming. Experiments show that addition of Zn and Al solutes have a softening effect at/below room temperature, attributed to solutes facilitating basal-prism-basal ...

2024

Machine learning potential for the Cu-W system

William Curtin

Combining the excellent thermal and electrical properties of Cu with the high abrasion resistance and thermal stability of W, Cu-W nanoparticle-reinforced metal matrix composites and nano-multilayers are finding applications as brazing fillers and shieldin ...

2024

Solute strengthening of prism edge dislocations in Mg alloys

William Curtin

The poor ductility of hcp Mg is attributed to the low activity of non-basal slip systems and so activation of prismatic slip can aid ductility in rolled sheets by providing three additional < a > Burgers vector slip systems. Experimental studies show that ...

ELSEVIER2024

Natural aging and vacancy trapping in Al-6xxx

William Curtin, Michele Ceriotti

Undesirable natural aging (NA) in Al-6xxx delays subsequent artificial aging (AA) but the size, composition, and evolution of clustering are challenging to measure. Here, atomistic details of early-stage clustering in Al-1% Mg-0.6%Si during NA are studied ...

Springer Heidelberg2023

A low-temperature prismatic slip instability in Mg understood using machine learning potentials

William Curtin, Xin Liu, Binglun Yin, Tao Liu

Prismatic slip in magnesium at temperatures T

PERGAMON-ELSEVIER SCIENCE LTD2023

Mechanism of thermally-activated prismatic slip in Mg

William Curtin

Prismatic slip of the screw dislocation in magnesium at temperatures greater than or similar to 150 K is understood to be governed by double-cross-slip of the stable basal screw through the unstable prism screw and back to the basal screw, with the activat ...

2023

Atomistic simulations reveal strength reductions due to short-range order in alloys

William Curtin

A theory for strengthening for multicomponent non-dilute alloys possessing short-range order (SRO) has recently been developed. The theory predicts that, in addition to a well-known athermal strengthening, there is a notable effect of SRO on the solute-dis ...

2023

Solute misfit and solute interaction effects on strengthening: A case study in AuNi

William Curtin, Shankha Nag, Binglun Yin

AuNi is a classic long-studied fcc alloy combining a very "large"atom (Au) and a very "small"atom (Ni), and the large atomic size misfits suggest very high strengthening. Here, AuNi is used as a model alloy for the testing of new strengthening theories in ...

2023

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

William Curtin, Carolina Baruffi, You Rao

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 ...

SPRINGERNATURE2023

Machine-learned interatomic potentials: Recent developments and prospective applications

William Curtin

High-throughput generation of large and consistent ab initio data combined with advanced machine-learning techniques are enabling the creation of interatomic potentials of near ab initio quality. This capability has the potential of dramatically impacting ...

Springer Heidelberg2023

High throughput synthesis enabled exploration of CoCrFeNi-based high entropy alloys

William Curtin, Xiao Zhou

To accelerate the exploration, screening, and discovery of structural high-entropy alloys with targeted properties, the newly developed High-Throughput Hot-Isostatic-Pressing based Micro-Synthesis Approach (HT-HIP-MSA) is employed to efficiently synthesize ...

JOURNAL MATER SCI TECHNOL2022

Machine learning for metallurgy V: A neural-network potential for zirconium

William Curtin, Pandula Manura Liyanage

The mechanical performance-including deformation, fracture and radiation damage-of zirconium is determined at the atomic scale. With Zr and its alloys extensively used in the nuclear industry, understanding that atomic scale behavior is crucial. The defect ...

2022

Modeling of precipitate strengthening with near-chemical accuracy: case study of Al-6xxx alloys

William Curtin, Yi Hu

Many metal alloys are strengthened by controlling precipitation to achieve an optimal peak-aged condi-tion where the strength-limiting processes of precipitate shearing and Orowan looping are thought to be comparable. Qualitative models have long captured ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Analytical models of short-range order in FCC and BCC alloys

William Curtin

A statistical-mechanics analysis is used to create analytic estimates for the short-range order (SRO) pa-rameters in FCC and BCC solid solution alloys as a function of composition and temperature. As in the classic quasi-chemical method, the analysis assum ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Screw vs. edge dislocation strengthening in body-centered-cubic high entrophy alloys and implications for guided alloy design

William Curtin, Francesco Maresca, Carolina Baruffi

Body-centered-cubic (BCC) high entropy alloys (HEAs) can show exceptionally high strength up to high temperatures. Mechanistic theories are needed to guide alloy discovery within the immense multicomponent HEA compositional space. Here, two new theories fo ...

SPRINGER HEIDELBERG2022