Publications associées à Embedded Shape-Memory Alloy Wires for Improved Performance of Self-Healing Polymers

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

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

CRACK SHIELDING MECHANISMS OF INTERLAYERED EPOXY MATERIALS UNDER QUASI-STATIC AND FATIGUE LOADING

Anastasios Vassilopoulos, Dharun Vadugappatty Srinivasan

This research explores the capability of PEI and PVDF thermoplastic interlayers to arrest cracks in epoxy materials modified with short-glass fibers and core-shell rubber particles. It also investigates the effect of interlayer position, the number of inte ...

Queen's University Belfast2023

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

Experimental behavior of iron-based shape memory alloys under cyclic loading histories

Elyas Ghafoori, Albano António De Abreu E Presa De Castro E Sousa, Diego Isidoro Heredia Rosa, Masoud Motavalli, Dimitrios Lignos, Alexander Riley Hartloper

The present paper investigates the behavior of iron-based shape memory alloys (Fe-SMAs) subjected to cyclic inelastic straining by means of uniaxial coupon experiments. The tests feature round bar coupons subjected to a broad range of uniaxial cyclic strai ...

2021

Stiff, Strong, Tough, and Highly Stretchable Hydrogels Based on Dual Stimuli-Responsive Semicrystalline Poly(urethane–urea) Copolymers

Pascal Alexander Schouwink, Nicolas Candau, Adrien Julien Demongeot, Oguzhan Oguz

There has been a considerable interest in developing stiff, strong, tough, and highly stretchable hydrogels in various fields of science and technology including biomedical and sensing applications. However, simultaneous optimization of stiffness, strength ...

2021

Behavior of iron-based Shape Memory Alloys under Cyclic Loading Histories

Albano António De Abreu E Presa De Castro E Sousa, Diego Isidoro Heredia Rosa, Masoud Motavalli, Dimitrios Lignos, Alexander Riley Hartloper

Shape memory alloys (SMAs) have gained considerable attention in a broad range of engineering applications. In particular, iron-based SMAs (Fe-SMAs) have been recently developed and used as a cost-effect method for prestressed-strengthening of civil struct ...

2019

Shape memory alloys in fibre-reinforced polymer composites

Véronique Michaud, Amaël Maximilien Cohades

This article reviews the current state-of-the-art in the applications of shape memory alloy (SMA) wires into high performance fibre reinforced polymer composite materials (FRPs). SMAs have been investigated to date to address four main areas of properties ...

2018

Stitched shape memory alloy wires enhance damage recovery in self-healing fibre-reinforced polymer composites

Véronique Michaud, Amaël Maximilien Cohades, Nathan Klaus Hostettler

A major issue in composite technology is matrix micro-cracking due to low-velocity impact damage, which may severely limit service lifetimes of composite parts. In a novel approach, remarkable levels of healing of impact damage are obtained using shape mem ...

2018

Functional composites with damage control and repair

Amaël Maximilien Cohades

Fibre Reinforced Polymer (FRP) composite structures are subjected during service to low energy impacts or unexpected loads, leading to damage. Microcracks are generally first formed in the matrix and can reach up to several hundred microns in thickness. In ...

EPFL2018

Strength and fracture of silicon second-phase particles in aluminium casting alloys

Martin Guillermo Mueller

The mechanical behaviour of metallic materials that have a microstructure composed of a brittle phase embedded in a ductile matrix is dictated by a complex interplay of factors such as local phase properties, cohesive properties, geometrical characteristic ...

EPFL2017

Thermal and damping behaviour of magnetic shape memory alloy composites

Véronique Michaud, Susanne Glock

Single crystals of ferromagnetic shape memory alloys (MSMA) exhibit magnetic field and stress induced strains via energy dissipating twinning. Embedding single crystalline MSMA particles into a polymer matrix could thus produce composites with enhanced ene ...

2015

Evaluation of the interfacial shear strength between pseudoplastic NiTi shape memory alloy wires and epoxy by the pull-out method

Yves Leterrier, Véronique Michaud, Edgars Sparnins

The interfacial shear strength (IFSS) between nickel-titanium (NiTi) shape memory alloy wires, characterized by a nonlinear stress-strain behavior, and epoxy matrix was determined by pull-out tests. Tests were carried out at several temperatures and levels ...

Institute of Physics2015

Fracture Toughness Healing in Epoxy Containing Both Epoxy and Amine Loaded Capsules

Véronique Michaud, Sam Neuser

The feasibility of self-healing epoxy matrices using the same chemistry as the matrix material, namely a standard epoxy-amine system, is demonstrated. The two-component self-healing system is encapsulated in core-shell structures using standard in situ cur ...

Wiley-V C H Verlag Gmbh2014

Tailored Capsule Based Self-Healing for Epoxy Matrix Composites

Sam Neuser

Self-healing materials are a novel class of materials able to repair structural or, more generally, functional damage to a part. They hence have the potential to improve reliability and cost effectiveness, because failure or loss of functionality may be po ...

EPFL2013

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

Internal Friction Phenomena at Polymeric and Metallic Shape Memory Materials. Experimental and Theoretical Results

Maria-Alexandra Paun

The internal friction phenomenon in metallic and polymeric shape memory materials is analyzed. The experimental results permit validation of a theoretical model which describes qualitatively the temperature dependence of the internal friction for the inves ...

2010

Tailored processing of epoxy with embedded shape memory alloy (SMA) wires

Véronique Michaud, Eva Kirkby, Julie O'Keane

We present the development of a low-temperature liquid composite moulding cure schedule that is compatible with the fabrication of shape memory alloy (SMA)–epoxy composite materials. With this process, the SMA wires do not need to be maintained in place wi ...

2009

Performance of self-healing epoxy with microencapsulated healing agent and shape memory alloy wires

Véronique Michaud, Eva Kirkby

We report the first measurements of a self-healing polymer that combines a microencapsulated liquid healing agent and shape memory alloy (SMA) wires. When a propagating crack ruptures the embedded microcapsules, the liquid healing agent is automatically re ...

2009

Active sensing and repair composites

Eva Kirkby

This thesis describes the development of a smart carbon fibre polymer composite that is capable of sensing its own damage and self-healing. Structural composites are used in the aerospace and marine industries, for example. During their lifetime impact eve ...

EPFL2009

Low temperature moulding of adaptive composites with embedded shape memory alloy wires

Véronique Michaud, Eva Kirkby, Julie O'Keane

The feasibility of using a low temperature liquid composite molding technique to produce smart composites with embedded shape memory alloys was investigated. The epoxy system of EPON 828 resin and DETA hardener was evaluated, with embedded NiTiCu shape mem ...

2008