Publications related to Effect of pre-existing immobile dislocations on the evolution of geometrically necessary dislocations during fatigue

DChannel: Accelerating Mobile ApplicationsWith Parallel High-bandwidth and Low-latency Channels

Interactive mobile applications like web browsing and gaming are known to benefit significantly from low latency networking, as applications communicate with cloud servers and other users' devices. Emerging mobile channel standards have not met these needs ...

USENIX ASSOC2023

Strengthening mechanisms in dilute and random solid solution high-entropy BCC alloys

Alireza Ghafarollahi

Tuning the mechanical properties of metals, including strength, through adjusting the type and/or concentration of added solute elements, has been recognized as an effective way to design and produce materials with desired or optimized mechanical propertie ...

EPFL2022

On the structure of (111) twist grain boundaries in diamond: atomistic simulations with Tersoff-type interatomic potentials

Carolina Baruffi

In nanocrystalline diamond thin films, the high grain boundary density and the associated grain boundary properties may dominate the overall material behavior. In the present work, we systematically investigate (111) twist grain boundaries in diamond carbo ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Brittle faulting of ductile rock induced by pore fluid pressure build‐up

Marie Estelle Solange Violay, Corentin Jean-Marie Rémi Noël, François Xavier Thibault Passelègue

Under upper crustal conditions, deformations are primarily brittle (i.e., localized) and accommodated by frictional mechanisms. At greater depth, deformations are ductile (i.e., distributed) and accommodated by crystal plasticity, diffusion mass transfer o ...

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

Concurrent multiscale modeling and theory of solute-strengthening for dilute and complex concentrated alloys

Shankha Nag

Under common processing conditions, both dilute and complex concentrated alloys are often realized as random alloys, with no correlation in the occupancy of lattice sites by the constituent atom types. The current thesis primary addresses two problems in r ...

EPFL2020

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

Large scale 3-dimensional atomistic simulations of screw dislocations interacting with coherent twin boundaries in Al, Cu and Ni under uniaxial and multiaxial loading conditions

Helena Van Swygenhoven, Satish I Rao

Large scale 3D atomistic simulations are performed to study the interaction between a curved dislocation with a dominant screw character and a Coherent Twin Boundary (CTB). Three FCC metals (Al, Cu and Ni) are addressed using 6 embedded-atom method (EAM) p ...

2019

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

Laue microdiffraction characterisation of as-cast and tensile deformed Al microwires

Andreas Mortensen, Helena Van Swygenhoven, Léa Deillon, Steven Van Petegem, Suzanne Godelieve Alphonsine Verheyden

Single-crystalline cast aluminium microwires with a diameter near 15 are characterised by Laue microdiffraction. A microwire in the as-cast condition exhibits a misorientation below over a length of 500 . The measured density of geometrically necessary dis ...

TAYLOR & FRANCIS LTD2019

Deformation-induced martensitic transformation under multiaxial loading

Wei-Neng Hsu

The deformation-induced martensitic transformation observed in specific materials can enhance their mechanical properties or result in functional properties. For example, the transformation induced plasticity (TRIP) effect results in a good combination of ...

EPFL2019

The interplay between deformation mechanisms in austenitic 304 steel during uniaxial and equibiaxial loading

Helena Van Swygenhoven, Wei-Neng Hsu, Efthymios Polatidis

The preferred deformation mechanisms with respect to the load path are studied in a medium stacking fault energy 304 austenitic stainless steel that exhibits both transformation induced plasticity and twinning induced plasticity. In situ neutron diffractio ...

2019

Privacy-Enhancing Technologies for Mobile Applications and Services

Thi Van Anh Pham

Over a third of the world 's population owns a smartphone. As generic computing devices that support a large and heterogeneous collection of mobile applications (apps), smartphones provide a plethora of functionalities and services to billions of users. B ...

EPFL2019

In situ tension-tension strain path changes of cold-rolled Mg AZ31B

Helena Van Swygenhoven, Steven Van Petegem

The mechanical behavior of cold-rolled Mg AZ31B is studied during in-plane multiaxial loading and tension-tension strain path changes performed on cruciform samples using in situ neutron diffraction and EBSD. The results are compared with uniaxial tension ...

2019

Dislocation Cross-Slip in Face-Centered Cubic Solid Solution Alloys

Wolfram Georg Nöhring

The mechanical strength of metals depends on their resistance against various microscopic deformation processes. In ductile metals, the most important process is shearing of the crystal lattice by dislocations. One of the fundamental aspects of dislocation ...

EPFL2018

Thermal Activation, Intermittency and Size Effects in the Plastic Deformation of Cast Aluminium Microwires

Suzanne Godelieve Alphonsine Verheyden

The microcasting process is a scaled-down investment casting process in which molten metal is pressure-infiltrated and directionally solidified in water-soluble moulds. It was previously developed to produce metallic microwires with a diameter (D) between ...

EPFL2018

A New Kinematic Model and Control Strategy for a Mobile Platform for Transporting Lightweight Manipulators

Andres San Millan Rodriguez

This work is concerned with the mechanical design and the description of the different components of a new mobile base for a lightweight mobile manipulator. These kinds of mobile manipulators are normally composed of multiple lightweight links mounted on a ...

MDPI2018

Privacy Preserving and Cost Optimal Mobile Crowdsensing using Smart Contracts on Blockchain

Boi Faltings, Sujit Prakash Gujar, Dimitrios Chatzopoulos

The popularity and applicability of mobile crowdsensing applications are continuously increasing due to the widespread of mobile devices and their sensing and processing capabilities. However, we need to offer appropriate incentives to the mobile users who ...

IEEE2018

Out-of-plane instability of thin reinforced concrete walls under seismic loading

Angelica Rosso

Out of plane instability of reinforced concrete walls is a failure mechanism observed rather recently following the earthquakes in Chile (2010) and New Zealand (2011). Global out of plane instability is a phenomenon that may occur in thin walls, subjected ...

EPFL2018

Atomistic simulations of dislocations in a model BCC multicomponent concentrated solid solution alloy

William Curtin, Céline Varvenne, Satish I Rao

Molecular statics and molecular dynamics simulations are presented for the structure and glide motion of a/2(111) dislocations in a randomly-distributed model-BCC Co16.67Fe36.67Ni16.67Ti30 alloy. Core structure variations along an individual dislocation li ...

Elsevier2017