Publications related to Shape-memory alloy

Near-Zero Parasitic Shift Flexure Pivots Based on Coupled n-RRR Planar Parallel Mechanisms

Simon Nessim Henein, Florent Cosandier, Loïc Benoît Tissot-Daguette, Etienne Frédéric Gabriel Thalmann

Flexure pivots, which are widely used for precision mechanisms, generally have the drawback of presenting parasitic shifts accompanying their rotation. The known solutions for canceling these undesirable parasitic translations usually induce a loss in radi ...

2024

Fabrication and Characterization of the Kirigami-Inspired SMA-Powered Actuator

Yves Perriard, Thomas Guillaume Martinez, Marjan Ghorbani, Sean Thomas, Guilain Lionel Germain Lang

This paper presents an innovative approach to creating Shape Memory Alloys (SMA)-based actuators that are lightweight, compact, and capable of providing large strokes. Inspired by the Kirigami structure, an SMA actuator is designed using the Ω -pattern, wh ...

2023

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

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

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

The General Crack Component Model for reversed cyclic shear

David Michael Volpe Ruggiero

A growing body of research has shown that reversed cyclic shear loading of reinforced concrete (RC) causes effects that are not accounted for in monotonic behavioral models. Notable among these effects are a reduction in shear strength and significant plas ...

2023

Modelling of metal alloys in realistic conditions with machine learning

Nataliya Lopanitsyna

Computer simulations based on statistical methods have emerged as a powerful tool for studying structure-property relationships at the atomistic level. However, to provide reliable insights into materials in realistic conditions, it is essential to accurat ...

EPFL2023

Zero Parasitic Shift Pivoting Kinematic Structures Based On Coupled N-RRR Planar Parallel Mechanisms For Flexure Pivot Design

Simon Nessim Henein, Florent Cosandier, Loïc Benoît Tissot-Daguette, Etienne Frédéric Gabriel Thalmann

Flexure pivots, which are widely used for precision mechanisms, generally have the drawback of presenting parasitic shifts accompanying their rotation. The known solutions for canceling these undesirable parasitic translations usually induce a loss in radi ...

ASME Amer Soc Mechanical Engineers2023

Electrode Impact on the Electrical Breakdown of Dielectric Elastomer Thin Films

Herbert Shea, Fabio Beco Albuquerque

Dielectric Elastomer Actuators (DEAs) enable the realization of energy-efficient and compact actuator systems. DEAs operate at the kilovolt range with typically microampere-level currents and hence minimize thermal losses in comparison to low voltage/high ...

MDPI2023

Modeling and analysis of miniaturized magnetorheological valve for fluidic actuation

Sofia Lydia Ntella

Fluidic actuation enables movement in a wide range of mechanical systems, from simple laboratory devices to more complex industrial machinery. Fluids are used to generate motion of mechanical pieces. The term "fluids" encompasses two types of technologies: ...

EPFL2023

Crystalline or amorphous? A critical evaluation of phenomenological phase selection rules

Johann Michler, Caroline Hain, Ashish Sharma

In this work, we reviewed the available phase selection rules comprising atomic size and topological aspects, entropies, enthalpies, melting points, valence and itinerant electron concentrations, as well as electronegativity, and validated them using a car ...

ELSEVIER SCI LTD2023

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

Micromechanics of oxide inclusions in ferrous alloys

Alejandra Inés Slagter

Oxide inclusions are inevitably present in steel as a direct consequence of the steelmaking process; as a result, a cubic centimetre of modern steel will generally contain about a million of these hard and brittle micrometre-sized ceramic particles. Inclus ...

EPFL2023

A multi-material robotic finger with integrated proprioceptive and tactile capabilities produced with a circular process

Josephine Anna Eleanor Hughes, Kai Christian Junge, Antonia Georgopoulou Papadonikolaki

When developing or designing biomimetic robotic fingers with rigid and soft components and integrated sensors, fabrication is often a bottle-neck when assembling and casting processing techniques are used. This study introduces a thermoplastic multi-materi ...

IEEE2023

Synthesis of Novel Integrated Actuators Powered by Shape Memory Alloys

Sean Thomas

In the modern age of miniaturisation, Smart Materials, a type of material that reacts mechanically to a certain stimulus, have become an integral part of this revolution. Among these materials, Shape Memory Alloys (SMAs), which have the highest volumetric ...

EPFL2022

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

Effect of post-heat treatment conditions on shape memory property in 4D printed Fe-17Mn-5Si-10Cr-4Ni shape memory alloy

Christian Leinenbach, Irene Ferretto

The influence of post-heat treatment on the microstructure and properties of 4D printed Fe-17Mn-5Si-10Cr-4Ni (wt. %) shape memory alloy (SMA) produced via a laser powder bed fusion process is investigated in this study. It is shown that heat-treatment temp ...

2022

Lifetime of dielectric elastomer actuators under DC electric fields

Fabio Beco Albuquerque

Dielectric elastomer actuators (DEAs) are interesting soft actuators compared to other actuation technologies owing to large achievable actuation strains, high energy density and fast actuation. However, because DEAs need to be operated under high electric ...

EPFL2022

A Low-Temperature Annealing Method for Alloy Nanostructures and Metasurfaces: Unlocking a Novel Degree of Freedom

Olivier Martin, Christian Santschi, Hsiang-Chu Wang, Jeonghyeon Kim, Debdatta Ray

The material and exact shape of a nanostructure determine its optical response, which is especially strong for plasmonic metals. Unfortunately, only a few plasmonic metals are available, which limits the spectral range where these strong optical effects ca ...

Wiley-V C H Verlag Gmbh2022

Non-Linear Behaviors In The Dynamics Of Complex Systems Through A Multifractal Hydrodynamic Model

Maria-Alexandra Paun

Some non-linear behaviors in the dynamics of complex systems using the Scale Relativity Theory in the form of Multifractal Hydrodynamic Model are analyzed. By assimilating any complex system to a mathematical multifractal-type object, it is shown that the ...

UNIV POLITEHNICA BUCHAREST, SCI BULL2022

Processability, microstructure and precipitation of a Zr-modified 2618 aluminium alloy fabricated by laser powder bed fusion

Christian Leinenbach, Xavier Maeder

Additive manufacturing offers the opportunity to produce complex geometries from novel alloys with improved properties. Adapting conventional alloys to the process-specific properties can facilitate rapid implementation of these materials in industrial pra ...

2022