Publications related to Oxy-fuel welding and cutting

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

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

Di Cui

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

Full-scale testing of European steel beams with reduced beam section under reversed cyclic loading

Dimitrios Lignos, Hiroyuki Inamasu

Steel beams with reduced beam section (RBS) are often used as part of prequalified connections in seismic regions. However, RBS connections are not as common in Europe. Reasons relate to easiness in fabrication, which requires on-site welding, and the seis ...

Springer Nature2022

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

Laser Scanning with Industrial Robot Arm for Raw-wood Fabrication

Yves Weinand, Petras Vestartas

This paper presents an integrated raw-wood fabrication workflow using an industrial robot arm and a laser scanner. The research is situated in a Swiss mountain forestry context where timber in its natural form could be applied locally without relying on la ...

2020

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

Fatigue Strength Upgrading of Cover Plate Ends by Welded Extensions in Existing Steel Bridge Girders

Alain Nussbaumer, Dimitrios Lignos, Vasileios Grigoriou

This paper investigates the fatigue upgrading of typical cover plate joint connections in existing steel bridge girders through cover plate extension. The upgraded detail is created by removing the existing transverse end weld, then welding the extension t ...

2018

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

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

Microfluidic Energy Conversion Devices

Seyyed Mohammad Hosseini Hashemi

Renewable resources of energy are increasing their share in our energy portfolio thanks to the technological advancements and an increasing environmental awareness in society. Although the cost of power generation from these resources has been reduced to r ...

EPFL2017

Proposed modeling approach of welding procedures for heavy steel plates

Dimitrios Lignos

A numerical modeling approach is proposed to assess the effectiveness of automatic submerged arc welding procedures for steel plates with thickness larger than 50 mm. The scope of study includes partial joint penetration butt welds, their numerical analysi ...

Elsevier2016

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

Effect of composite beam action on the hysteretic behavior of fully-restrained beam-to-column connections under cyclic loading

Dimitrios Lignos, Ahmed Mohamed Ahmed Elkady

This paper assesses the composite beam effects on the hysteretic behavior of fully-restrained beam-to-column connections as part of steel moment-resisting frames (MRFs) designed in highly seismic regions. A practical approach is developed based on availabl ...

American Institute of Steel Construction (AISC)2016

Hand Impedance Measurements During Interactive Manual Welding With a Robot

Aude Billard, Mustafa Suphi Erden

This paper presents a study of hand impedance measurements comparatively across ten professional and 14 novice manual welders, when they are performing tungsten inert gas (TIG) welding interactively with the KUKA lightweight robot arm (LWR). The results sh ...

Ieee-Inst Electrical Electronics Engineers Inc2015

Fatigue behaviour and detailing of slotted tubular connection

Alain Nussbaumer, Luís Costa Borges, Cláudio Alexandre Pereira Baptista, Santosh Yadav

Tubular elements are used in steel structures not only for bracing of other members but also as cross girders diaphragms. They are a competitive solution both due to the lightweight and structural efficiency. Slotted tube-to-plate connections are the natur ...

2015

Shape-Dependence of Pd Nanocrystal Carburization during Acetylene Hydrogenation

Lioubov Kiwi, Rocio Micaela Crespo Quesada, Fernando Cardenas Lizana

This interdisciplinary work combines the use of shape- and size-defined Pd nanocrystals (cubes of 10 and 18 nm, and octahedra of 37 nm) with in situ techniques and DFT calculations to unravel the dynamic phenomena with respect to Pd reconstruction taking p ...

Amer Chemical Soc2015

Robotic training for hand movements during manual welding with real-time alarm feedback

Aude Billard, Mustafa Suphi Erden

Purpose - The purpose of this study is to develop a robotic training system for the hand movements during manual welding. The system provides real-time notice-feedback with sound or light alarms, whenever the welding hand vibrates beyond the nominal level ...

Emerald2015

End-point Impedance Measurements at Human Hand during Interactive Manual Welding with Robot

Aude Billard, Mustafa Suphi Erden

This paper presents a study of end-point impedance measurement at human hand, with professional and novice manual welders when they are performing Tungsten Inert Gas (TIG) welding interactively with the KUKA Light Weight Robot Arm (LWR). The welding torch ...

2014

Upscaling of Friction Welding of Wood for structural Applications

Benjamin Hahn

The present work deals with the large-scale application of the friction welding bonding technology on timber. The investigations that are described in the following were carried out on a prototype of a welding machine that was previously developed for the ...

EPFL2014

Experimental and numerical characterisation of heat flow during flame cutting of thick steel plates

Jean-Marie Drezet, Jean-Paul Lebet, Raphaël Thiébaud

Temperatures measurements during flame cutting of a thick steel plate and measurements of the extension of the fusion and heat affected zones and Vickers hardness after cutting have been performed. Additionally, a 3-D thermal model for simulation of flame- ...

Elsevier2014