Skip to main content
  • DE
  • EN
  • FR
Paul Scherrer Institut (PSI) Paul Scherrer Institut (PSI)
Suche
Paul Scherrer Institut (PSI) Paul Scherrer Institut (PSI)

Hauptnavigation

  • Labs & User ServicesOpen mainmenu item
    • Overview
    • Research at PSI
    • Research Divisions and Labs
    • Facilities and Instruments
    • Research Initiatives
    • PSI User Labs
    • Scientific Highlights
    • Scientific Events
    • Scientific Career
    • Useroffice
  • VisitorsOpen mainmenu item
    • Overview
    • Contact
    • How to find us
    • Public Events
    • Visitor Centre psi forum
    • Schülerlabor iLab
    • Center for Proton Therapy
  • IndustryOpen mainmenu item
    • Overview
    • Technology Transfer
    • Spin-off Companies
    • PARK innovAARE
  • Our ResearchOpen mainmenu item
    • Current topics from our research
    • Matter and Material
    • Human Health
    • Energy and Environment
    • Large Research Facilities
    • Brochures
    • Films
    • Media Corner
  • Career & Further EducationOpen mainmenu item
    • Job Opportunities
    • Personnel Policy
    • Working at PSI
    • Equal Opportunities, Diversity & Inclusion
    • Training and Further Education
    • Vocational Training
    • PSI Education Centre
    • Support Program "PSI Career Return Program"
    • PSI-FELLOW/COFUND
  • About PSIOpen mainmenu item
    • PSI in brief
    • Strategy
    • Guiding principles
    • Facts and figures
    • Organisational structure
    • Suppliers and customers
    • Customers E-Billing
    • IT and Computing
    • Safety at PSI (in German)

You are here:

  1. PSI Home
  2. Our Research
  3. Current topics from our research
  4. New material with magnetic shape memory

Secondary navigation

Our Research

  • Current topics from our research Expanded submenu item
    • Matter and Material
    • Human Health
    • Energy and Environment
    • ESI Platform
    • Large research facilities
    • Project SLS 2.0
    • Topic Overview
    • Chronological Overview
      • Archiv
  • 5232 – The magazine of the Paul Scherrer Institute
    • Contact
  • Brochures
  • Films
    • Virtual Tour
  • Media corner
    • Media Releases
    • Social Media Newsroom
4 June 2019

New material with magnetic shape memory

Media Releases Matter and Material Materials Research Research Using Synchrotron Light

Researchers at the Paul Scherrer Institute PSI and ETH Zurich have developed a new material whose shape memory is activated by magnetism. It retains a given shape when it is put into a magnetic field. It is a composite material consisting of two components. What is special about the new material is that, unlike previous shape-memory materials, it consists of a polymer and droplets of a so-called magnetorheological fluid embedded in it. Areas of application for this new type of composite material include medicine, aerospace, electronics and robotics. The researchers are now publishing their results in the scientific journal Advanced Materials.

Streifen des neuen Materials im Magnetfeld
Laura Heyderman (left), Paolo Testa (centre) and Eric Dufresne with a strip of the new material in a magnetic field
(Photo: Paul Scherrer Institute/Mahir Dzambegovic)
Paolo Testa mit einem Modell der prinzipiellen Struktur des formerinnernden Materials
Paolo Testa, first author of the study, with a model of the overall structure of the shape-memory material
(Photo: Paul Scherrer Institute/Mahir Dzambegovic)

It looks like a magic trick: A magnet moves away from a black, twisted band and the band relaxes –without any further effect (see video). What looks like magic can be explained by magnetism. The black ribbon consists of a composite of two components: a silicone-based polymer and small droplets of water and glycerine in which tiny particles of carbonyl iron float. The latter provide the magnetic properties of the material and its shape memory. If the composite material is forced into a certain shape with tweezers and then exposed to a magnetic field, this shape is retained even when the tweezers are removed. Only when the magnetic field is also removed does the material return to its original shape.

So far, comparable materials have consisted of a polymer and embedded metal particles. Instead, researchers at PSI and ETH Zurich used droplets of water and glycerine to insert the magnetic particles into the polymer. In this way, they produced a dispersion similar to that found in milk. In milk, tiny fat droplets are finely dispersed in an aqueous solution. These are essentially responsible for the white colour.

Similarly, the droplets of the magnetorheological liquid are finely distributed in the new material. "Since the magnetically sensitive phase dispersed in the polymer is a liquid, the forces generated when a magnetic field is applied are much larger than previously reported", explains Laura Heyderman, head of the Mesoscopic Systems Group at PSI and a professor at ETH Zurich. If a magnetic field acts on the composite material, it stiffens. “This new material concept could only come about through teamwork between groups with expertise from two completely different areas – magnetic and soft materials", says Heyderman.

The video shows how the new material is forced into a loop shape with tweezers. Then a ring-shaped magnet is raised. Even if the tweezers are removed, the material retains its shape in the magnetic field. When the magnet is lowered again and the magnetic field is removed, the material returns to its original shape.
(Video: Paul Scherrer Institute - ETH Zurich/Paolo Testa)

Shape memory through alignment with the magnetic field

The researchers studied the new material with the help of the Swiss Light Source SLS, among other things. With the X-ray tomographic images produced with this light source, they found that the length of the droplets in the polymer increases under the influence of a magnetic field and that the carbonyl iron particles in the liquid align at least partially along the magnetic field lines. These two factors increase the stiffness of the material tested by up to 30 times.

The fact that the shape memory of the new material is activated by magnetic fields offers further advantages in addition to higher force. Most shape-memory materials react to changes in temperature. In medical applications, two problems arise as a result. First, excessive heat damages the body's own cells. Second, it is not always possible to guarantee uniform warming of an object that remembers its shape. Both disadvantages can be avoided by switching on the shape memory with a magnetic field.

Mechanically active materials for medicine and robotics

"With our new composite material, we have taken another important step towards simplifying components in a wide range of applications such as medicine and robotics", says ETH Zurich and PSI materials scientist Paolo Testa, first author of the study. "Our work therefore serves as the starting point for a new class of mechanically active materials."

Numerous applications in medicine, space flight, electronics, and robotics are conceivable for shape-memory materials. For example, catheters that are pushed through blood vessels to the surgical site in the body during minimally invasive operations could change their stiffness. This has the advantage that they only have to solidify when needed and therefore produce fewer side effects such as thromboses – for example when sliding through a blood vessel. In space exploration, shape-memory materials are in demand as a kind of tyres for rover vehicles that inflate or fold up again on their own. In electronics, soft functional materials can be found as flexible power or data cables, for example in so-called wearables, i.e., devices worn in clothing or directly on the body. Shape memory also opens up new possibilities in robotics; for example, shape-memory materials can perform mechanical movements without a motor.

The researchers are now publishing their results in the scientific journal Advanced Materials.

Text: Paul Scherrer Institute/Sebastian Jutzi


About PSI

The Paul Scherrer Institute PSI develops, builds and operates large, complex research facilities and makes them available to the national and international research community. The institute's own key research priorities are in the fields of matter and materials, energy and environment and human health. PSI is committed to the training of future generations. Therefore about one quarter of our staff are post-docs, post-graduates or apprentices. Altogether PSI employs 2100 people, thus being the largest research institute in Switzerland. The annual budget amounts to approximately CHF 407 million. PSI is part of the ETH Domain, with the other members being the two Swiss Federal Institutes of Technology, ETH Zurich and EPFL Lausanne, as well as Eawag (Swiss Federal Institute of Aquatic Science and Technology), Empa (Swiss Federal Laboratories for Materials Science and Technology) and WSL (Swiss Federal Institute for Forest, Snow and Landscape Research). (Last updated in May 2019)

Contact

Prof. Dr. Laura Heyderman
Mesoscopic Systems
ETH Zurich - Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
Telephone: +41 56 310 26 13, e-mail: laura.heyderman@psi.ch [English, German, French]

Paolo Testa
Mesoscopic Systems

ETH Zurich - Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
Telephone: +41 56 310 3391, e-mail: paolo.testa@mat.ethz.ch [English, Italian]

Prof. Dr. Eric. R. Dufresne
Laboratory for Soft and Living Materials, Department of Materials

ETH Zurich, 8093 Zurich, Switzerland
Telephone: +41 44 633 44 84, e-mail: eric.dufresne@mat.ethz.ch [English]

Original Publication

Magnetically Addressable Shape-memory and Stiffening in a Composite Elastomer
Paolo Testa, Robert W. Style, Jizhai Cui, Claire Donnelly, Elena V. Borisova, Peter M. Derlet, Eric R. Dufresne and Laura J. Heyderman

Advanced Materials, 4 June 2019
DOI: 10.1002/adma.201900561

 

Sidebar

5232 Ausgabe 3 2020

5232 — Das Magazin des Paul Scherrer Instituts

03/2020
in German
View in issuu.com
Download

Visitor Centre psi forum

Experience research live


The iLab School Laboratory

Experience Science - Explore Research

top

Footer

Paul Scherrer Institut

Forschungsstrasse 111
5232 Villigen PSI
Switzerland
How to find us

Imprint
Terms and Conditions

Login

Telephone: +41 56 310 21 11
Telefax: +41 56 310 21 99
Contact form

Visitor Centre psi forum
School Lab iLab (in German)
Center for Proton Therapy

Follow us: Twitter (in English) LinkedIn Youtube Issuu RSS

Quicklinks

  • Phone Book/People Search
  • Digital User Office
  • Technology transfer
  • PSI Publications
  • Computing
  • Safety (in German)
  • Job Opportunities
  • Vocational Training (in German)
  • Suppliers
  • Customers E-Billing
  • PSI Guest House
  • PSI Gastronomie (in German)

For the media

  • Media Contact
  • Media Releases
  • Social Media Newsroom
  • Facts and Figures
  • PSI in brief
  • Films
  • DE
  • EN
  • FR