Publications associées à Characterisation of Laser Welds, between Nitinol and Stainless Steel Wires

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

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

EBSD study of variant reorientation, texture, and twin formation in a martensitic NiTi alloy deformed in compression

Mathijs Pieter van der Meer, Cyril Cayron, Roland Logé, Junfeng Xiao

Martensitic crystallography plays a vital role in the texture evolution and mechanical properties in Nickel-Titanium (NiTi) shape memory alloys when subjected to deformation. However, their microstructural changes during deformation are not well known and ...

Pergamon-Elsevier Science Ltd2023

Experimental Investigation of Instability-Free Welded Moment Connections With Simplified Weld Details

Dimitrios Lignos, Andronikos Skiadopoulos

In capacity designed steel moment resisting frames, inelastic deformations are mostly concentrated in the steel beams and the column fixed ends of the first story. This design concept limits the participation of the column web’s panel zone in the energy di ...

2023

Simultaneous strength and ductility enhancement of wire-arc directed energy deposited Al-Cu alloy by interlayer laser shock peening

Ke Huang, Yandong Jing

Wire-arc directed energy deposition (wire-arc DED), recognized for its ability to produce large-scale parts, has gained considerable attention. However, a critical issue with this method is the high prevalence of internal porosity defects found in the manu ...

Elsevier Science Sa2023

The influence of lattice misfit on screw and edge dislocation-controlled solid solution strengthening in Mo-Ti alloys

William Curtin, Carolina Baruffi, You Rao

Mo-Ti alloys form solid solutions over a wide range of compositions, with lattice misfit parameters increasing significantly with titanium content. This indicates a strong increase in the critical stress for edge dislocation motion. Here, we probe the tran ...

SPRINGERNATURE2023

Bringing casting to microfabrication: processing and deformation of microcastings

Luciano Borasi

This work extends the range of pathways for the production of metallic microcomponents by downscaling metal casting. This is accomplished by using either of two different molding techniques, namely femtosecond laser micromachining or lithographic silicon m ...

EPFL2023

Multi-scale characterization and modeling of notched strength and translaminar fracture in hybrid thin-ply composites based on different carbon fiber grades

Guillaume Clément Broggi

Owing to their high specific stiffness and strength, Carbon Fiber Reinforced Composites (CFRP) are ideal candidates for the development of lightweight high-performance structures. Within this family, thin-ply composites allow for wider design freedom and p ...

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

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

Strong silicon oxide inclusions in iron

Andreas Mortensen, Léa Deillon, Alejandra Inés Slagter, Joris Pierre Everaerts

Oxide inclusions are ubiquitous in steel and are known to affect, generally in a negative sense, the mechanical performance of steel products. Micromechanical properties of those phases are therefore important, yet they have remained largely unexplored. We ...

2022

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

Cyril Cayron, Roland Logé, 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

Tailored deformation behavior of 304L stainless steel through control of the crystallographic texture with laser-powder bed fusion

Christian Leinenbach, Roland Logé, Efthymios Polatidis, Markus Strobl

Laser-powder bed fusion (L-PBF) has gained significant research interest, not only for its profound advantage of producing near-net shape complex geometries of metallic parts, but also for the possibility of producing tailored microstructures. Here we expl ...

ELSEVIER SCI LTD2022

Thermal Modelling and Experimental Validation in the Perspective of Tool Steel Laser Polishing

Alexandre Masserey, Eric Boillat, Bastian Meylan

Laser polishing (LP) is a process that allows a significant reduction of the surface roughness of a metal workpiece via re-melting a shallow layer of material. However, the practical use of LP is limited due to the difficulty of satisfying the high surface ...

MDPI2022

Thermophysical and thermomechanical properties of basalt-phenolic FRP rebars under high temperature

Thomas Keller, Hongwei Zhu, Ting Li, Jiahui Shen

An experimental investigation was conducted on the thermophysical and thermomechanical properties of phenolic-basalt fiber-reinforced polymer (P-BFRP) rebars subjected to high temperature. As a comparison, vinylBFRP (V-BFRP) and epoxy-BFRP (E-BFRP) rebars ...

ELSEVIER SCI LTD2022

Weakening effect of various pore fluids on the tensile strength of granite

Guanyi Lu

Laboratory three-point bending experiments are carried out to evaluate the effect of various fluids on the tensile strength of granite. The granite specimens were tested under both dry and saturated conditions. The fluids used to saturate the granite inclu ...

SPRINGER HEIDELBERG2022

Giant hardening response in AlMgZn(Cu) alloys

William Curtin, Daniel John Gilles Marchand

This study presents a thermomechanical processing concept which is capable of exploiting the full industrial application potential of recently introduced AlMgZn(Cu) alloys. The beneficial linkage of alloy design and processing allows not only to satisfy th ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Cyclic metal plasticity model parameters with limited information: a constrained optimization approach

Albano António De Abreu E Presa De Castro E Sousa, Dimitrios Lignos, Alexander Riley Hartloper

Tensile test data for structural steels are ubiquitous. Yet, the information monotonic loading provides with respect to the material's characteristics is limited. Notably, features of inelastic response to cyclic loading, such as the Bauschinger eect, can ...

2021

APT/TEM characterization of the element segregation in ferritic/martensitic steels after irradiation in SINQ

Lijuan Cui

Ferritic /martensitic (FM) steels are among the most important materials in various nuclear applications. As radiation-induced segregation (RIS) is one of the major factors for embrittlement of nuclear materials, thereofre it is essential to study the RIS ...

EPFL2021

Atomic scale investigations of fracture in metal alloys

Eleanor Yi Kei Mak

The demand for metal alloys with superior structural performance in industrial applications continues to increase, as does the need for more-energy efficient materials and methods. Many materials that are otherwise attractive for structural applications ar ...

EPFL2021