Publications related to Zirconium alloys

Atomic level insight into irradiation effects in nuclear fuel materials

Microstructural evolution during in-pile irradiation, radiation damage effects and fission products behavior in UO2 nuclear fuel are key issues in understanding and for the modeling of the performance as well as safety characteristics of nuclear fuels in t ...

EPFL2024

EBSD study of variant reorientation, texture, and twin formation in a martensitic NiTi alloy deformed in compression

Cyril Cayron, Roland Logé, Mathijs Pieter van der Meer, Junfeng Xiao

Martensitic crystallography plays a vital role in the texture evolution and mechanical properties in Nickel-Titanium (NiTi) shape memory alloys when subjected to deformation. However, their microstructural changes during deformation are not well known and ...

Pergamon-Elsevier Science Ltd2023

Extension of the OFFBEAT fuel performance code to finite strains and validation against LOCA experiments

Andreas Pautz, Carlo Fiorina, Alessandro Scolaro, Edoardo Luciano Brunetto

The mechanical analysis of nuclear fuel behavior under base-irradiation conditions has traditionally been performed adopting the small-strain approximation. However, many cases of interest for fuel behavior involve the occurrence of large rod deformations ...

ELSEVIER SCIENCE SA2023

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

Towards coupling conventional with high-fidelity fuel behavior analysis tools

Andreas Pautz, Carlo Fiorina, Alessandro Scolaro, Edoardo Luciano Brunetto

Multi-dimensional fuel performance codes have the potential to enhance the understanding of complex phenomena affecting fuel integrity, but their application is often limited by the high computational cost. Recognizing that many multi-dimensional aspects s ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Delayed Hydride Cracking in Irradiated and Unirradiated Zircaloy-2 Cladding

Aaron William Colldeweih

Zirconium alloys used in the nuclear industry are exposed to extreme conditions undergoing high levels of irradiation damage and corrosion. Zircaloy-2 is used as nuclear fuel cladding in boiling water reactors and for the encapsulation of the spallation ta ...

EPFL2022

Deformation twinning mechanism in magnesium at the microscale: strain rate, temperature and orientation effects

Nicolò Maria Della Ventura

The project aims to validate some recent theoretical developments on the deformation twinning nucleation mechanism in HCP metals through small-scale mechanic experiments. To this end, a systematic investigation of the mechanical response of pure magnesium ...

EPFL2022

Processability, microstructure and precipitation of a Zr-modified 2618 aluminium alloy fabricated by laser powder bed fusion

Christian Leinenbach, Xavier Maeder

Additive manufacturing offers the opportunity to produce complex geometries from novel alloys with improved properties. Adapting conventional alloys to the process-specific properties can facilitate rapid implementation of these materials in industrial pra ...

2022

Evolution of deformation twinning mechanisms in magnesium from low to high strain rates

Roland Logé, Cyril Cayron, Johann Michler, Xavier Maeder, Amit Sharma, Nicolò Maria Della Ventura, Manish Jain

We present a systematic investigation of {10 (1) over bar2} extension twinning mechanism in single crystal magnesium micropillars deformed over seven orders of magnitude of strain rate, from 10(-4) to 500 s(-1), revealing how the accommodation of newly for ...

ELSEVIER SCI LTD2022

Theory of twin strengthening in fcc high entropy alloys

William Curtin, Recep Ekin Kubilay

Twinning in fcc High Entropy Alloys (HEAs) has been implicated as a possible mechanism for hardening that enables enhanced ductility. Here, a theory for the twinning stress is developed analogous to recent theories for yield stress. Specifically, the stres ...

2021

Local excitations in amorphous solids

Wencheng Ji

Amorphous solids are structurally disordered. They are very common and include glasses, colloids, and granular materials, but are far less understood than crystalline solids. Key aspects of these materials are controlled by the presence of excitations in w ...

EPFL2021

{10(1)over-bar2} twinning mechanism during in situ micro-tensile loading of pure Mg: Role of basal slip and twin-twin interactions

Roland Logé, Johann Michler, Xavier Maeder, Amit Sharma, Daniele Casari, Nicolò Maria Della Ventura

An SEM in situ uniaxial tensile testing setup allowing HR-EBSD acquisition during deformation was used to study the extension twinning mechanism in magnesium(Mg) at the micron scale. Structures were fabricated with two different crystal orientations, respe ...

2021

Theory of kink migration in dilute BCC alloys

William Curtin, Alireza Ghafarollahi

Plastic deformation in elemental BCC metals and dilute alloys is controlled by the slower of the kink pair nucleation and kink migration processes along screw dislocations. In alloys nucleation is facilitated and migration inhibited, leading to a concentra ...

2021

Atomic Scale Investigations into the Origins of Ductility in Mg Alloys

Rasool Ahmad

The industrial applications of Mg, the lightest structural metal, and abundant in Earth's crust, are hampered by its low intrinsic ductility and low fracture toughness at room temperature which is attributed to the underlying less symmetric and plastically ...

EPFL2020

Design of Ductile Rare-Earth-Free Magnesium Alloys

William Curtin, Binglun Yin, Zhaoxuan Wu, Rasool Ahmad

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- ...

SPRINGER INTERNATIONAL PUBLISHING AG2020

Analysis of double cross-slip of pyramidal I < c plus a > screw dislocations and implications for ductility in Mg alloys

William Curtin, Zhaoxuan Wu, Rasool Ahmad

Solute accelerated cross-slip of pyramidal < c + a > screw dislocations has recently been recognized as a crucial mechanism in enhancing the ductility of solid-solution Mg alloys. In pure Mg, cross-slip is ineffective owing to the energy difference between ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Effect of dislocations, Al-3(Sc,Zr) distribution and ageing temperature on theta ' precipitation in Al-Cu-(Sc)-(Zr) alloys

Baptiste Thomas Jean Rouxel

The 2xxx series aluminium alloys, which contain Cu as the main addition element, are widely used in the aerospace industry for their high specific strength. The main strengthening contribution in these alloys comes from the formation of theta' precipitates ...

ELSEVIER SCI LTD2020

Deformation mechanisms in a superelastic NiTi alloy: An in-situ high resolution digital image correlation study

Helena Van Swygenhoven, Efthymios Polatidis

An in-situ high resolution digital image correlation investigation during uniaxial tensile deformation reveals the recoverable and the non-recoverable strain mechanisms in a Ni51Ti49 alloy with a mean grain size of 35 mu m. Recoverable strain is due to the ...

2020

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

William Curtin, Helena Van Swygenhoven, 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

Designing high ductility in magnesium alloys

William Curtin, Binglun Yin, Zhaoxuan Wu, Rasool Ahmad

The thermally activated pyramidal-to-basal (PB) transition of (c + a) dislocations, transforming glissile pyramidal dissociated core structures into sessile basal dissociated ones, lies at the origin of low ductility in pure magnesium (Mg). Solute-accelera ...

PERGAMON-ELSEVIER SCIENCE LTD2019