Publications associées à Brazing

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials Part-III: Experimental verification of conversion products and infiltration depth by infiltration of Si-Zr alloy into mixed SiC/ graphite preforms

Ludger Weber, Annapaola Parrilli, Caroline Hain, Alberto Ortona, Manoj Kondibhau Naikade

Porous carbonaceous preforms, made from graphite and silicon carbide (SiC) powders, with varying graphite powder mass fractions and particle sizes, were infiltrated at 1500 degrees C and 1700 degrees C by Si-8 at. pct Zr alloy to produce dense Si-Zr-SiC co ...

ELSEVIER SCI LTD2023

Improved Waste Heat Management and Energy Integration in an Aluminum Annealing Continuous Furnace Using a Machine Learning Approach

François Maréchal, Daniel Alexander Florez Orrego, Réginald Germanier, Mohammad Andayesh, Manuele Gatti

Annealing furnaces are critical for achieving the desired material properties in the production of high-quality aluminum products. In addition, energy efficiency has become more and more important in industrial processes due to increasing decarbonization r ...

2023

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

Micro-addition of Fe in highly alloyed Cu-Ti alloys to improve both formability and strength

Roland Logé, Cyril Cayron, Baptiste Thomas Jean Rouxel

Cu-Be alloys provide excellent electrical and mechanical properties, but present serious health hazards during manufacturing. Among alternative alloys, the Cu-Ti system has the highest yield strength; however, Ti cannot be easily solutionized at concentrat ...

ELSEVIER SCI LTD2022

Microstructure Selection in Laser Remelted Fe-C-Si Alloys

Wilfried Kurz, Philippe Gilgien

Laser surface remelting at various velocities has been employed to study the selection of microstructures of high-purity Fe-C-Si alloys containing nominally 3.2 to 4.2 wt.% C and 1 to 3 wt.% Si. The microstructure of the remelted region consisted of metast ...

WALTER DE GRUYTER GMBH2021

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

Mapping Spatial Distribution of Pores in an Additively Manufactured Gold Alloy Using Neutron Microtomography

Roland Logé, Jamasp Jhabvala, Hossein Ghasemi Tabasi, Markus Strobl, Michaël Meyer

A crucial criterion for the quality of the additively manufactured parts is the porosity content for achieving an acceptable final relative density. In addition, for jewelry applications, visible pores are unacceptable at or in the vicinity of the surface. ...

2021

Combining alloy and process modification for micro-crack mitigation in an additively manufactured Ni-base superalloy

Roland Logé, Christian Leinenbach, Jamasp Jhabvala, Xavier Maeder, Hossein Ghasemi Tabasi, Toni Ivas, Rafal Wróbel

The additive manufacturing (AM) of the gamma' precipitation strengthened Ni-base superalloys still remains a challenge due to their susceptibility to micro-cracking. Post-processing, such as HIPing, has been shown to heal the micro-cracks but it remains de ...

ELSEVIER2020

Hydrogen-sieving single-layer graphene membranes obtained by crystallographic and morphological optimization of catalytic copper foil

Kumar Varoon Agrawal, Shiqi Huang, Shaoxian Li

Gas separation membranes based on single-layer-graphene are highly attractive because the size of graphene nanopores can be tuned to separate gases by the size-sieving mechanism. A prerequisite for this, the synthesis of high-quality polycrystalline single ...

2020

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

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

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

Fatigue properties of as-welded and post-weld-treated high-strength steel joints: The influence of constant and variable amplitude loads

Alain Nussbaumer, Halid Can Yildirim, Heikki Tapani Remes

In HSS welded structures, HFMI allows fatigue strength improvement factors by inducing compressive residual stresses, cold-worked surface region and modifying the weld toe shape. According to the literature, the factors are proposed based on failures at CA ...

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

Development of a new family of phosphorous-free Pt-based bulk metallic glasses

Ludger Weber, Maïté Blank, Hamed Kazemi, Cyrill Werner Cattin

New BMGs exhibiting strong glass forming ability combined with high hardness have been developed based on the Pt-Si-B ternary system. The effects of partial substitution of platinum by transition metals of the group iron, cobalt, nickel, and copper, as wel ...

Elsevier2017

Influence of icosahedral short range order on diffusion in liquids: A study on Al-Zn-Cr alloys

Michel Rappaz, Güven Kurtuldu

It has been shown recently that minute additions of Cr in Al-Zn alloys refine the solidified grain structure and induce multiply-twinned grains which can only be explained if the icosahedral symmetry is considered (Kurtuldu et al., 2013). It has been sugge ...

Elsevier2016

Quasi-Instantaneous Bacterial Inactivation on Cu-Ag Nanoparticulate 3D Catheters in the Dark and Under Light: Mechanism and Dynamics

César Pulgarin, Juan Kiwi, Sami Rtimi, Rosendo Sanjines

The first evidence for Cu-Ag (50%/50%) nanoparticulate hybrid coatings is presented leading to a complete and almost instantaneous bacterial inactivation in the dark (

Amer Chemical Soc2016

Microstructure of Cu-Ag Uniform Nanoparticulate Films on Polyurethane 3D Catheters: Surface Properties

César Pulgarin, Juan Kiwi, Sami Rtimi, Rosendo Sanjines

The preparation, characterization, and antibacterial testing of Cu-Ag sputtered polyurethane (PU) catheters are addressed in this study. PU catheters with different atomic ratios Cu:Ag have been sputtered and led to different optical properties as followed ...

Amer Chemical Soc2016

Microstructural stability of ODS steels in cyclic loading

Cécile Hébert

The remarkable microstructural stability of high chromium steels prepared by powder metallurgy and strengthened by dispersion of nanometric yttrium oxides in cyclic loading at high temperatures is reported. Contrary to the continuous cyclic softening and p ...

Wiley-Blackwell2015