Publications de Francesco Maresca

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

High energy barriers for edge dislocation motion in body-centered cubic high entropy alloys

William Curtin, Francesco Maresca, Alireza Ghafarollahi, Recep Ekin Kubilay

Recent theory proposes that edge dislocations in random body-centered cubic (BCC) high entropy alloys have high barriers for motion, conveying high strengths up to high temperatures. Here, the energy barriers for edge motion are computed for two model allo ...

NATURE RESEARCH2021

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

William Curtin, Francesco Maresca, Rui Feng

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 ...

Nature Portfolio2021

Mechanistic origin of high strength in refractory BCC high entropy alloys up to 1900K

William Curtin, Francesco Maresca

The body centered cubic (BCC) high entropy alloys (HEAs) MoNbTaW and MoNbTaVW show exceptional strength retention up to 1900K. The mechanistic origin of the retained strength is unknown yet is crucial for finding the best alloys across the immense space of ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Theory of screw dislocation strengthening in random BCC alloys from dilute to "High-Entropy" alloys

William Curtin, Francesco Maresca

Random body-centered-cubic (BCC) "High Entropy" alloys are a new class of alloys, some having high strength and good ductility at room temperature and some having exceptional high-temperature strength. There are no theories of strengthening of screw disloc ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Measurement and prediction of the transformation strain that controls ductility and toughness in advanced steels

Helena Van Swygenhoven, William Curtin, Francesco Maresca, Efthymios Polatidis

New-generation multi-phase martensitic steels derive their high strength from the body-centered cubic (BCC) phase and high toughness from transformation of the metastable face-centered cubic (FCC) austenite that transforms into martensite upon loading. In ...

PERGAMON-ELSEVIER SCIENCE LTD2020

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

William Curtin, Francesco Maresca, Binglun Yin

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 ...

2020

Solute/screw dislocation interaction energy parameter for strengthening in bcc dilute to high entropy alloys

William Curtin, Francesco Maresca, Alireza Ghafarollahi

Strengthening, i.e. increased stress required to move a dislocation, in dilute or complex alloys arises from the totality of the interaction energies between the solutes and an individual dislocation. Prevailing theories for strengthening in bcc alloys con ...

IOP PUBLISHING LTD2019

Contribution of austenite-martensite transformation to deformability of advanced high strength steels: From atomistic mechanisms to microstructural response

William Curtin, Francesco Maresca

2018

Ferrite slip system activation investigated by uniaxial micro-tensile tests and simulations

Francesco Maresca

2018

Screw dislocation structure and mobility in body centered cubic Fe predicted by a Gaussian Approximation Potential

Nicola Marzari, William Curtin, Daniele Dragoni, Francesco Maresca

The plastic flow behavior of bcc transition metals up to moderate temperatures is dominated by the thermally activated glide of screw dislocations, which in turn is determined by the atomic-scale screw dislocation core structure and the associated kink-pai ...

2018

The austenite/lath martensite interface in steels: Structure, athermal motion, and in-situ transformation strain revealed by simulation and theory

William Curtin, Francesco Maresca

The austenite/martensite (fcc/bcc) interface is prevalent across many new classes of high-strength steels, and yet both its fundamental structure and its mechanism of motion remain uncertain in spite of decades of research. Here, atomistic simulations are ...

2017