Publications associées à Soudage laser

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

Geometric tolerances of welded connections with inelastic panel zones

Dimitrios Lignos, Andronikos Skiadopoulos, Ce Wen

Prequalified beam-to-column connections in steel moment resisting frames usually concentrate inelastic deformations in the steel beam ends. As such, nonlinear geo-metric instabilities (i.e., local buckling) may occur in these regions at modest lateral drif ...

Ernst & Sohn2023

Hysteretic behaviour of welded connections with highly inelastic panel zones

Dimitrios Lignos, Andronikos Skiadopoulos

The current practice in capacity-designed steel moment resisting frames (MRFs) worldwide allows for limitedshear yielding in the column web panel zone. As such, inelastic deformations concentrate near the beam ends, thereby leading to flexural stre ...

Ernst & Sohn2023

Adaptive Laser Welding Control: A Reinforcement Learning Approach

Silvio Zanoli, Giulio Masinelli

Despite extensive research efforts in the field of laser welding, the imperfect repeatability of the weld quality still represents an open topic. Indeed, the inherent complexity of the underlying physical phenomena prevents the implementation of an effecti ...

2020

Recommendations for Improved Welding Procedures for Thick Steel Plates Through Thermo-Mechanical Analysis

Dimitrios Lignos

Welding of steel plates is accompanied by residual stresses that increase as the constraint provided by the welded components becomes greater. Consequently, crack initiation has been reported after welding thick plates due to the high residual stresses dev ...

2019

Multiaxial ultra low cycle fatigue in welded high strength steel structural components

Alain Nussbaumer, Albano António De Abreu E Presa De Castro E Sousa

Extreme events often subject regions of structural steel components to large inelastic strains. In conditions such as earthquakes, exceptional winds gusts or tides the loading scenario is cyclical, variable amplitude and frequently multiaxial in nature, an ...

2019

Residual stresses of friction melt bonded aluminum/steel joints determined by neutron diffraction

Jean-Marie Drezet

Near interfacial residual stresses are investigated in a joint composed of aluminum alloy and dual phase steel. A small step neutron diffraction scan was initially performed to determine the weld interface position along the measured transverse cross secti ...

ELSEVIER SCIENCE SA2019

Method and device for fabrication of 3d multi - material (composite) parts by selective laser melting combined with laser welding and cutting

Roland Logé, Nikola Kalentics

The method of manufacturing objects made of a first primary material such as ceramic, metallic or polymer materials on at least one workstation by selective laser melting (SLM) comprises the addition of at least a secondary material different from the prim ...

2017

Stress intensity factors for axial semi-elliptical surface cracks and embedded elliptical cracks at longitudinal butt welded joints of steel-lined pressure tunnels and shafts considering weld shape

Anton Schleiss, Pedro Filipe De Almeida Manso, Alexandre Jean Pachoud

When for steel liners of pressure tunnels and shafts high-strength steels are used, welded joints are subject to the risk of hydrogen induced cold-cracking in the base material. Longitudinal butt welded joints are critical regions as they are loaded transv ...

Elsevier2017

Design guidelines for remote laser welding in automotive assembly lines

Ian Anthony Stroud, Jumyung Um

Remote laser welding which has benefits for both productivity and energy saving is receiving increased attention for automotive assembly lines. Introducing this innovative equipment requires a redesign process for assembly elements, for example to substitu ...

Springer London Ltd2017

Study on the mixed dynamic recrystallization mechanism during the globularization process of laser-welded TA15 Ti-alloy joint under hot tensile deformation

Ke Huang, Gang Liu, Jie Zhao

In this article, the hot deformation mechanism of a laser-welded near a TA15 Ti-alloy joint was studied by hot tensile tests conducted at temperatures ranging from 800 degrees C to 900 degrees C with strain rates ranging from 1.0 x 10(-1) s(-1) to 1.0 x 10 ...

Elsevier2017

Robotic Assistance by Impedance Compensation for Hand Movements While Manual Welding

Aude Billard, Mustafa Suphi Erden

In this paper, we present a robotic assistance scheme which allows for impedance compensation with stiffness, damping, and mass parameters for hand manipulation tasks and we apply it to manual welding. The impedance compensation does not assume a preprogra ...

Institute of Electrical and Electronics Engineers2016

New parametric equations to estimate notch stress concentration factors at butt welded joints modeling the weld profile with splines

Anton Schleiss, Pedro Filipe De Almeida Manso, Alexandre Jean Pachoud

For fatigue life estimation as well as for fatigue testing analysis of welded structures by local stresses approaches, the stress concentration factor (SCF) at the weld must be known. Full penetration butt welded joints are extensively used in steel struct ...

Elsevier2016

Study and Modelling of the Melt Pool Dynamics during Selective Laser Sintering and Melting

Tatiana Polivnikova

Selective laser sintering (SLS) and Selective Laser Melting (SLM) are parent layer manufacturing processes that allow generating complex 3D parts by consolidating layers of powder material on top of each other. Consolidation is obtained by processing the s ...

EPFL2015

Three-dimensional chemical analysis of laser-welded NiTi–stainless steel wires using a dual-beam FIB

Michel Rappaz, Aïcha Hessler-Wyser, Marco Cantoni, Pierre Burdet, Jonas Vannod

The biomedical industry has an increasing demand for processes to join dissimilar metals, such as laser welding of NiTi and stainless steel wires. A region of the weld close to the NiTi interface, which previously was shown to be prone to cracking, was fur ...

Elsevier2013

Total energy estimation model for remote laser welding process

Ian Anthony Stroud, Jumyung Um

The issues in the energy-efficiency process have much interest in the automotive industry. The energy criteria are also important in machine selection as well as productivity when new equipment is introduced on a shop floor. Remote laser welding having ben ...

Elsevier Science Bv2013

Three Dimensional Microanalysis by Energy Dispersive Spectrometry : Improved Data Processing

Pierre Burdet

This thesis is focused on a combined microscopy technique: energy dispersive spectrometry (EDS) is extended to a three dimensional (3D) microanalysis using a so-called "dual-beam microscope": a scanning electron microscope (SEM) equipped with a focused ion ...

EPFL2012

Laser Welding of Nickel-Titanium and Stainless Steel Wires : Processing, Metallurgy and Properties

Jonas Vannod

The biomedical industry has an increasing demand for dissimilar metal joining processes, which are used for complex configuration designs, such as guidewires and other intravascular interventional devices. Their production becomes more and more challenging ...

EPFL2011

Intergranular penetration of liquid gold into stainless steel

Michel Rappaz, Léa Deillon, Jean-Daniel Wagnière, Denis Favez

Intergranular penetration of liquid 18 K gold into a superaustenitic stainless steel, which occurs during laser welding of these two materials, has been studied using a C-ring device which can be put under tensile stresses by a screw. It is shown that liqu ...

Elsevier2011

Au-Fe alloy solidification and solid-state transformations

Michel Rappaz, Jean-Daniel Wagnière

In order to better understand the microstructure that forms during laser welding of an 18 carat gold and an austenitic stainless steel, solidification of the Au-Fe binary analog has been studied using thermal analysis and interrupted Bridgman experiments. ...

Elsevier2010