Publications associées à Solder

Control of intermetallics in the interface in directed energy deposition of titanium on stainless steel 316L

Application of a single metal or alloy is often restricted by its properties from optimal combination of performance and cost. Therefore, there is a vast need of joining dissimilar metals for various applications in biomedical, aerospace, automobile and ma ...

EPFL2023

Machine learning for metallurgy IV: A neural network potential for Al-Cu-Mg and Al-Cu-Mg-Zn

William Curtin, Daniel John Gilles Marchand

Most metallurgical properties, e.g., dislocation propagation, precipitate formation, can only be fully understood atomistically but most phenomena and quantities of interest cannot be measured experimentally. Accurate simulation methods are essential but f ...

2022

Solar reduction of carbon dioxide on copper-tin electrocatalysts with energy conversion efficiency near 20%

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jing Gao, Meng Xia, Yuhang Liu, Dan Ren, Jun Li

Solar-driven carbon dioxide reduction has witnessed a renaissance in the past decades, but the system suffers from low reaction rates. Here the authors develop a copper/tin-oxide electrocatalyst, achieving a new benchmark solar-to-CO energy conversion effi ...

Nature Portfolio2022

Development of High-Strength Aluminum Alloys for Additive Manufacturing

Marvin Lennard Schuster

Metal additive manufacturing (AM) offers the possibility to rapidly produce complex geometries that are not achievable with conventional manufacturing methods. The two most common technologies, Laser Powder Bed Fusion (LPBF) and Direct Metal Deposition (DM ...

EPFL2022

Surface energy contributions to the work of infiltration in metal matrix composite processing

Andreas Mortensen, Gionata Schneider

The work needed to mechanically drive molten metal into a porous solid preform when producing a composite material by infiltration can significantly exceed the energy change required for thermodynamically reversible infiltration. We measure, by quantitativ ...

2021

Numerical Model of Rapidly Solidified Droplets of Al-33 Wt Pct Cu Eutectic Growth

Michel Rappaz, Jonas Valloton

Rapid solidification of Al-Cu droplets of eutectic composition was carried out using Impulse Atomization (a type of drop tube). Two distinct morphologies were observed: an irregular undulated eutectic assumed to form during recalescence, followed by a regu ...

SPRINGER2022

Study and characterization of silicon metal alloys systems for the reactive infiltration process of ceramic matrix composites

Manoj Kondibhau Naikade

Silicon infiltrated silicon carbide (SiSiC) is one of the most promising and economical non-oxide ceramic matrix composites for high-temperature structural applications. In recent years infiltration by Si-alloys instead of pure Si has become popular to avo ...

EPFL2021

Influence of Minor Cr Additions on Crystal Growth in Rapidly Solidified Al-20Zn Alloys

Michel Rappaz

It has been discovered quite recently that Icosahedral Short-Range Order (ISRO) of atoms in the liquid phase of metallic alloys surrounding some trace elements added to the melt can influence both the nucleation and growth of the primary phase. In this wor ...

2020

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

Influence of thermo-mechanical processing on ordering kinetics in 18 karat red gold alloy

Marina Garcia Gonzalez

The aim of this project is to understand the correlation between alloy composition and the build-up of internal stresses in 18 carat Au-Ag-Cu alloys under thermo-mechanical loads. The copper rich end of this ternary system exhibits order-hardening of the e ...

EPFL2020

Design guidelines for Al-12%Si latent heat storage encapsulations to optimize performance and mitigate degradation

Sophia Haussener, Selmar Rudolf Binder

We provide detailed insight into the growth kinetics of intermetallic layers formed at the interface of molten Al-12%Si with cylindrical encapsulations of 316L stainless steel. This knowledge is relevant for the design and operation of high-temperature lat ...

ELSEVIER2020

Tribological behaviour of galvanic gold coatings reinforced with silica nanoparticles

Stefano Mischler, Anna Neus Igual Muñoz

Electroplated composite Au/SiO2 coatings on a nickel substrate have been produced by dispersing an emulsion of silica nanoparticles (20 nm in diameter) in an industrial hard-gold bath. The tribological behaviour of the Au/SiO2 coatings with different SiO2 ...

2020

Synthesis of metal oxide photoanodes for water splitting using nanocrystals as precursors

Chethana Janardhana Gadiyar

Photoelectrochemical (PEC) water splitting devices are envisioned to play a key role in the societal transition towards sustainable energy sources. In this context, multinary metal oxide semiconductors are the most promising candidates for the role of phot ...

EPFL2020

First principles study of the effect of hydrogen in austenitic stainless steels and high entropy alloys

William Curtin, Xiao Zhou

Hydrogen (H) embrittlement in multicomponent austenitic alloys is a serious limitation to their application in many environments. Recent experiments show that the High-Entropy Alloy (HEA) CoCrFeMnNi absorbs more H than 304 Stainless Steel but is less prone ...

2020

A Study on the Characteristics of Cu-Mn-Dy Alloy Resistive Thin Films

Ho-Yun Lee

Cu-Mn-Dy resistive thin films were prepared on glass and Al2O3 substrates, which was achieved by co-sputtering the Cu-Mn alloy and dysprosium targets. The effects of the addition of dysprosium on the electrical properties and microstructures of annealed Cu ...

2019

Dynamic wetting in pressure-infiltration of ceramic particle preforms by molten metal

Gionata Schneider

This thesis investigates the interaction between mechanically induced flow of a liquid metal into a porous solid, and kinetic effects at the triple line. The approach is experimental and focuses on metal-ceramic systems for which the literature gives value ...

EPFL2019

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

Preliminary Tests of Soldered and Diffusion-Bonded Splices Between Nb3Sn Rutherford Cables for Graded High-Field Accelerator Magnets

Pierluigi Bruzzone, Davide Uglietti, Mithlesh Kumar, Vincenzo D'Auria

High-field accelerator magnets of the next generation will require coil grading in order to decrease the amount of superconductor and hence the magnet cost. The joints between Nb3Sn conductor grades must have low electrical resistance (

IEEE Institute of Electrical and Electronics Engineers2019

Appearance of polished 18 karat gold surfaces: linking aesthetics to surface features

Leili Batooli

Impeccable appearance of surfaces is a key constraint in high-end jewelry and watch manufacturing. Based on long tradition in the industry, appearance of products is assessed by trained individuals through visual inspection in designated intervals on the p ...

EPFL2019

Influence of Ir Additions and Icosahedral Short Range Order (ISRO) on Nucleation and Growth Kinetics in Au-20.5Wt Pct Cu-4.5Wt PctAg Alloy

Michel Rappaz

Based on detailed EBSD analyses, Kurtuldu et al. (Acta Mater. 70:240-248, 2014) have explained the grain refinement of Au-12.5 wt pctCu-12.5 wt pctAg (yellow gold) by the addition of minute amounts of Ir in terms of icosahedral quasicrystal (iQC)-mediated ...

SPRINGER2019