Publications associées à Cold working

Dislocation Hardening in a New Manufacturing Route of Ferritic Oxide Dispersion-Strengthened Fe-14Cr Cladding Tube

The microstructure evolution associated with the cold forming sequence of an Fe-14Cr-1W-0.3Ti-0.3Y2O3 grade ferritic stainless steel strengthened by dispersion of nano oxides (ODS) was investigated. The material, initially hot extruded at 1100 degrees C an ...

MDPI2024

Laser powder bed fusion of Fe-based shape memory alloys for novel structural metamaterials and "smart" structures

Irene Ferretto

Laser powder bed fusion (LPBF) is a powder-based additive manufacturing (AM) technique, which shows great potential in the production of complex-shaped parts with unprecedented design freedom. In addition, it allows for an active manipulation of the micros ...

EPFL2023

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

Influence of Joule Effect Heating on Recrystallization Phenomena in Inconel 718

Roland Logé, Mathijs Pieter van der Meer

In this article, the Joule effect heating influence on recrystallization phenomena in the Inconel 718 nickel-based superalloy is investigated in details. On the one hand, static recrystallization kinetic studies at 1020 degrees C after cold deformation up ...

SPRINGER2021

In situ characterization of work hardening and springback in grade 2 alpha-titanium under tensile load

Helena Van Swygenhoven

Plastic effects during sheet metal forming can lead to undesirable distortions in formed components. Here, the three-stage work hardening and plastic strain recovery ("springback") in a cold-rolled, alpha-phase commercially pure titanium is examined. Inter ...

2019

The surprising influence of continuous alternating electric current on recrystallization behaviour of a cold-rolled Aluminium alloy

Cyril Cayron, Roland Logé, Ke Huang

Pronounced acceleration of recrystallization in cold worked metals is generally observed during annealing with additional high density electric current pulses. In this work, continuous alternating current of low density was applied to heat cold-rolled samp ...

Elsevier2017

Influence of geometrical imperfections and flaws at welds of steel liners on fatigue behavior of pressure tunnels and shafts in anisotropic rock

Alexandre Jean Pachoud

The recent development of high-strength (HSS) weldable steels has enlarged the range of design alternatives for the optimization of high-head steel-lined pressure tunnels and shafts (SLPT&S) in the hydropower industry. With the liberalization of the Europe ...

EPFL2017

Very high cycle fatigue tests with quenched and self-tempered reinforcement steel bars

Eugen Brühwiler, Alain Nussbaumer, Marina Rocha Pinto Portela Nunes

Investigations on the fatigue strength of steel reinforcement bars (rebars) mainly involves fatigue tests with hot rolled (HR) and cold worked (CW) steels. However, in the last few decades, HR and CW rebars were replaced by quenched and selftempered (QST) ...

Springer Verlag2016

On the sluggish recrystallization of a cold-rolled Al–Mn–Fe–Si alloy

Roland Logé, Ke Huang

Annealing of supersaturated AA3xxx alloys at low temperatures usually results in sluggish recrystallization kinetics. This is due to the joint effect of the following factors: low nucleation rate, reduced grain boundary mobility, and large amount of fine p ...

Springer Verlag2016

Numerical Modeling of Tube Forming by HPTR Cold Pilgering Process

Roland Logé

For new fast-neutron sodium-cooled Generation IV nuclear reactors, the candidate cladding materials for the very strong burn-up are ferritic and martensitic oxide dispersion strengthened grades. Classically, the cladding tube is cold formed by a sequence o ...

Springer Verlag2016

The Influence of Processing Conditions on Microchemistry and the Softening Behavior of Cold Rolled Al-Mn-Fe-Si Alloys

Ke Huang, Ning Wang

Using different homogenization treatments, different initial microchemistry conditions in terms of solid solution levels of Mn, and number densities and sizes of constituents and dispersoids were achieved in an Al-Mn-Fe-Si model alloy. For each homogenized ...

2016

Mean field modelling of dynamic and post-dynamic recrystallization during hot deformation of Inconel 718 in the absence of δ phase particles

Roland Logé

Dynamic and post-dynamic recrystallization kinetics were investigated during hot-working of Inconel 718 as a function of temperature,strain and strain rate in the single phase domain.The post-dynamic evolution was found to be extremely fast and impacting s ...

Elsevier2016

Évolution microstructurale et propriétés mécaniques d'un alliage Co-Ni-Cr

Raffaele Cosimati

This study concerns the evolution of the thermomechanical properties of new high-performance materials. In particular, we focus on the relationship between the microstructure and the mechanical properties of a superalloy based on Co-Ni-Cr. Superalloys are ...

EPFL2016

Comparative study and quantification of cementite decomposition in heavily drawn pearlitic steel wires

Daniele Mari, Aude Marie Agnès Lamontagne

Heavily cold-drawing was performed on a pearlitic steel wire and on an ultra-low carbon (ULC) steel wire in order to highlight and quantify the microstructural changes caused by this type of deformation. Both global techniques (thermoelectric power, electr ...

Elsevier Science Sa2015

Geometrical and material characterisation of quenched and self-tempered steel reinforcement bars

Eugen Brühwiler, Alain Nussbaumer, Marina Rocha Pinto Portela Nunes

Quenched and self-tempered (QST) steel reinforcement bars (rebars) are manufactured by Thermex or Tempcore processes. Characterization studies of QST rebars are mostly limited to reveal the hardened outer layer and some improved mechanical properties compa ...

Asce-Amer Soc Civil Engineers2016

Microstructural influence on the scatter in the fatigue life of steel reinforcement bars

Eugen Brühwiler, Alain Nussbaumer, Marina Rocha Pinto Portela Nunes

Fatigue damage accumulation and failure of steel reinforcement bars (rebars) is a stochastic process. Scatter can be influenced by the sensitivity of the short crack growth to the microstructural features, especially near the fatigue limit. This work inves ...

Elsevier2015

Effect of heterogeneously distributed pre-existing dispersoids on the recrystallization behavior of a cold-rolled Al–Mn–Fe–Si alloy

Ke Huang

It is well known that strong concurrent precipitation, mainly located along grain/subgrain boundaries, results in a coarse and elongated grain structure, and unusual sharp P {011} and/or M {113} texture components during annealing of supersatur ...

Elsevier2015

Magnesium interatomic potential for simulating plasticity and fracture phenomena

William Curtin, Michael Frederick Francis

Magnesium has multiple dislocation and twinning systems with starkly different properties, which make its plastic deformation strongly anisotropic and highly complex. Existing empirical interatomic potentials fail to capture the full scope of these propert ...

Institute of Physics2015

Quantitative analysis of deformation in hollow cylinder tests on anisotropic clay formations

Vincent Labiouse, Gioacchino Viggiani, Shuang You

A series of triaxial laboratory experiments are performed on thick-walled hollow cylindrical samples of boom clay. The aim of this testing program is to better understand the anisotropic deformation during the excavation. The testing conditions are similar ...

2015

Fatigue behaviour prediction of steel reinforcement bars using an adapted Navarro and De Los Rios model

Eugen Brühwiler, Alain Nussbaumer, Marina Rocha Pinto Portela Nunes

Fatigue cracks tend to initiate on the rebar surface and therefore, the surface conditions may control their fatigue behaviour. This study investigates the influence of surface microstructure and roughness dispersion on the scatter and fatigue life of hot ...

Elsevier Sci Ltd2015