Publications associées à Impact of in situ nanomechanics on physical metallurgy

Design for demise applied to spacecraft structural panels and experiments for ClearSpace One platform

With growing awareness of the vulnerability of the near-Earth space region and the anticipated surge in satellite objects, efforts are underway to assess and implement various mitigation strategies. These aim to minimize the impact of space activities and ...

EPFL2024

Spinel Protective Coatings for Solid Oxide Cell (SOC) Interconnects (ICs)

Samaneh Daviran

Abstract The degradation of metal interconnects (ICs) in Solid Oxide Cells (SOCs) primarily results from chromium (Cr) oxide scale growth on stainless-steel substrates, causing ohmic loss and air-side electrode poisoning by Cr. This thesis addresses these ...

EPFL2024

Evaluation of Interface and Residual Strain of NiTi Layer Deposited on NiTiX Substrate by Laser Powder Bed Fusion

Elyas Ghafoori, Christian Leinenbach, Irene Ferretto, Mahbod Golrang, Mahshid Memarian

This study investigates the microstructure and properties of functionally graded NiTi alloy bilayers. The NiTi layer is printed by laser powder bed fusion on a NiTiX (where X is Hf or Cu) substrate prepared by vacuum arc remelting. Specimens produced with ...

Wiley-V C H Verlag Gmbh2024

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

Origin of the enhanced pseudo-elasticity of additively manufactured Fe-17Mn-5Si-4Ni-10Cr-(V, C) shape memory alloy fabricated by laser powder bed fusion

Christian Leinenbach, Irene Ferretto

This study investigated the origin of the enhanced pseudo-elasticity of additively manufactured vanadium carbide-containing Fe-based shape memory alloys. The aged samples with two different starting microstructures, as-built and solution-treated, showed co ...

Elsevier Science Sa2023

Tensile and creep-rupture response of additively manufactured nickel-based superalloy CM247LC

Christian Leinenbach, Rafal Wróbel

Tensile and creep rupture properties of crack-free CM247LC alloy, processed via laser powder bed fusion, have been characterised in this work at temperatures up to 1000 & DEG;C. The subject alloy matches or even exceeds the tensile performance of its direc ...

ELSEVIER2023

Vacancy segregation and intrinsic coordination defects at (111) twist grain boundaries in diamond

Christian Brandl, Carolina Baruffi

High radiation damage resistance has become increasingly important for applications of functional materials in harsh environments. The high radiation damage resistance diamond cubic carbon is a unique material which is considered for radiation environments ...

Pergamon-Elsevier Science Ltd2023

Rapid grain boundary diffusion in foraminifera tests biases paleotemperature records

Lukas Baumgartner, Anders Meibom, Jaroslaw Hubert Stolarski, Arthur Adams, Deyanira Graciela Cisneros Lazaro, Jinming Guo

The paleoseawater temperature record from the oxygen isotope compositions of fossil foraminifera tests may be biased by up to about 1 degrees C due to grain-boundary diffusion alone, according to isotope exchange experiments on foraminifera tests. The oxyg ...

2023

Simple shear extrusion versus equal channel angular pressing: A comparative study on the microstructure and mechanical properties of an Mg alloy

Cyril Cayron, Roland Logé, Aryan Rezaei Rad

Two severe plastic deformation (SPD) techniques of simple shear extrusion (SSE) and equal channel angular pressing (ECAP) were employed to process an extruded Mg -6Gd -3Y -1.5Ag (wt%) alloy at 553 K for 1, 2, 4 and 6 passes. The microstructural evolutions ...

KEAI PUBLISHING LTD2023

Micromechanics of oxide inclusions in ferrous alloys

Alejandra Inés Slagter

Oxide inclusions are inevitably present in steel as a direct consequence of the steelmaking process; as a result, a cubic centimetre of modern steel will generally contain about a million of these hard and brittle micrometre-sized ceramic particles. Inclus ...

EPFL2023

Atomic scale volume and grain boundary diffusion elucidated by in situ STEM

Johann Michler, Amit Sharma, Laszlo Pethö, Xavier Maeder

Diffusion is one of the most important phenomena studied in science ranging from physics to biology and, in abstract form, even in social sciences. In the field of materials science, diffusion in crystalline solids is of particular interest as it plays a p ...

Nature Portfolio2023

Microstructure et usinabilité d'alliages de titane béta-métastable

Loïc Favre

Titanium has become in recent years an interesting material in many applications that require a combination of high mechanical properties and low density. It has the peculiarity of undergoing an allotropic transformation at 882°C. Below this temperature, ...

EPFL2023

Highly Efficient and Air-Stable Inorganic Perovskite Solar Cells Enabled by Polylactic Acid Modification

Feng Liu, Yong Ding

Inorganic perovskite solar cells (PSCs) suffer from serious carrier recombination and open-circuit voltage loss because of surface defects and unfavorable energy level alignment. Herein, a polylactic acid (PLA) modification approach to improve the performa ...

WILEY-V C H VERLAG GMBH2023

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

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

Effect of Y2O3 dispersoids on microstructure and creep properties of Hastelloy X processed by laser powder-bed fusion

Christian Leinenbach

Laser powder bed fusion (LPBF) was used to consolidate powders of a Ni-Cr-Fe-Mo alloy (Hastelloy X) blended with 1 wt% Y2O3 nanometric powders. The nearly-dense, crack-free specimens, with and without oxide dispersion strengthening (ODS), exhibit high-aspe ...

ELSEVIER2022

Three-dimensional in situ imaging of single-grain growth in polycrystalline In2O3:Zr films

Quentin Thomas Jeangros, Michael Elias Stückelberger, Monica Morales Masis

Understanding grain morphology and kinetics of solid-phase crystallization is important for controlling the functional properties of polycrystalline materials. Here, in situ coherent X-ray diffraction imaging and transmission electron microscopy elucidate ...

SPRINGERNATURE2022

Weakening effect of various pore fluids on the tensile strength of granite

Guanyi Lu

Laboratory three-point bending experiments are carried out to evaluate the effect of various fluids on the tensile strength of granite. The granite specimens were tested under both dry and saturated conditions. The fluids used to saturate the granite inclu ...

SPRINGER HEIDELBERG2022

Revealing Morphology Evolution of Lithium Dendrites by Large-Scale Simulation Based on Machine Learning Force Field

Mouyi Weng, Wentao Zhang

Solving the dendrite growth problem is critical for the development of lithium metal anode for high-capacity batteries. In this work, a machine learning force field model in combination with a self-consistent continuum solvation model is used to simulate t ...

WILEY-V C H VERLAG GMBH2022

Demonstrating and Unraveling a Controlled Nanometer-Scale Expansion of the Vacancy Defects in Graphene by CO2

Kumar Varoon Agrawal, Luis Francisco Villalobos Vazquez de la Parra, Kuang-Jung Hsu

A controlled manipulation of graphene edges and vacancies is desired for molecular separation, sensing and electronics applications. Unfortunately, available etching methods always lead to vacancy nucleation making it challenging to control etching. Herein ...

Wiley-VCH Verlag GmbH2022