Tuesday, November 3, 2009
Terminology
Thermoelastic martensitic transfomations - interaction between structural state and magnetic subsystem
Heusler Alloy - Ni-Mn-Ga alloy system 1995
Twinning disconnections
Magnostriction - both the spontaneous ferromagnetic ordering and/or externally stimulated magnetization process in solids are always accompanied by volume and shape changes, large magnostriction 1996
What are MSMAs?
Magnetic Shape Memory Alloys or MSMAs are a newly researched memory shape alloys that can have from 10-20% strain when a magnetic field is applied. The visible strain is due to reorientation of the martensitic variants within the alloy's microstructure. The advantage of MSMAs over conventional SMAs is in their ability to be operated over a much broader frequency range rather than just through heat transfer.
Monday, November 2, 2009
Magnetic Shape Memory Alloys Reference List
Research & Applications
http://www.technologyreview.com/business/12484/
(need subscription)
http://www.technologyreview.com/communications/20016/?a=f
(smart foam)
http://smart.tamu.edu/publications/docs/Papers/2005/magnetic_field_induced.pdf
http://engineering.tamu.edu/research/magazine/2006/batteries/
http://www.dpg-verhandlungen.de/2009/dresden/ma26.pdf
http://www.magneticshape.de/
Coordinator of the SPP 1239:
Dr. Sebastian Fähler
IFW Dresden
Helmholtzstraße 20
01069 Dresden
++49 (0351) 4659-588
s.faehler (at the domain) ifw-dresden.de
http://www.nsf.gov/news/news_summ.jsp?cntn_id=110901
http://dunand.northwestern.edu/
David Dunand
847.491.5370
dunand(@northwestern.edu)
Materials Science & Eng
2220 Campus Drive
Evanston, IL 60208
http://coen.boisestate.edu/departments/faculty.asp?ID=44
Peter Müllner , Ph.D.
Professor, co-MSE graduate coordinator
Faculty
Office: MEC 302F
Tel: 208-426-5136
Fax: 208-426-2470
E-mail: petermullner@boisestate.edu
http://spie.org/x648.html?pf=true%0D%0A%09%09%09%09&product_id=598153
http://txikilike.blogspot.com/2008/05/magnetic-shape-memory-alloys.html
http://smart.tamu.edu/publications/docs/Proceedings/2004/spie2004.pdf
http://www.ornl.gov/~jxz/alns/PRB_Stipcich_04_NiMnGa.pdf
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APPLAB000094000016161908000001&idtype=cvips&gifs=yes
http://www.informaworld.com/smpp/content~db=all?content=10.1080/14786430500363858
http://www.ttp.net/0-87849-381-6.html
http://www.scientific.net/AMR.52.221
http://www.sciencecentric.com/news/article.php?q=08051604
http://rdmag.com/News/2009/09/Materials-Smart-Memory-Foam-Made-Smarter/
http://www.reactivereports.com/30/30_3.html
http://www.nsf.gov/news/mmg/mmg_disp.cfm?med_id=65786&from=mn
http://web.mit.edu/bobohand/www/fsma.html
http://www.seas.harvard.edu/vlassak_group/web_v1_Prita.htm
http://www.tkk.fi/Units/AES/projects/prlaser/msm.htm
Companies & Products
http://www.ifw-dresden.de/institutes/imw/sections/21/funct-magn-mat/ferromagnetic-shape-memory-alloys
http://www.ifw-dresden.de/institutes/imw/sections/26/magnetic-films-folder/magnetic-shape-memory-alloy-films
Leibniz Institute for Solid State and Materials Research Dresden
Phone +49 (3 51) 46 59-0
Dr. h. c. Dipl.-Finw. Rolf Pfrengle
Telefon +49 (0)3 51/46 59 200
r.pfrengle@ifw-dresden.de
http://www.mrs.org/s_mrs/doc.asp?CID=11403&DID=202772
Materials Research Society
Manfred Wuttig
Dept. of Materials Science and Engineering
University of Maryland
1110C Chem-Nuc 090
College Park, MD 20742
301-405-5212
Magnetic Shape Memory Alloys Books
Ferromagnetic Shape Memory Alloys: Selected, Peer Reviewed Papers from the International Conference on Ferromagnetic Shape Memory Alloys, Held at S.n.bose ... Basic Scie (Advanced Materials Research,) by Lluis Manosa, S. R. Barman, and P. K. Mukhopadhyay
Advances in Shape Memory Materials: Magnetic Shape Memory Alloys (Materials Science Forum), V. A. Chernenko
Magnetic Shape Memory Alloys (Materials Research Society Symposium Proceedings), Materials Research Society
Shape Memory Effects in Alloys, Jeff Perkins
Thursday, October 22, 2009
Monday, October 19, 2009
Hypothetical Case Study
Imagine spaces that utilize one of our basic principles of physics, magnetism, as a catalyst for environmental interior power, beauty, and comfort.
In the fields of smart materials and nanotechnology research is being conducted in order to someday have structures composed of elements that react as simply as your herb garden through complex genius of design.
Architecture of Tomorrow Components
First it is imperative that we define the smart materials that will be explored for use in this building.
1. Shape Memory Alloy and Magnetic Shape Memory Alloy
This will be used as cladding for both the interior and exterior of the building. The exterior will be of shape memory alloy which is controlled by temperature, as the sun comes up each day the cladding will react by opening up to the sun and exposing the nanowire "farms" growing on the silica substrate(windows) of the bulding exterior. The interior spaces will be lined with magnetic memory shape alloy which, when field induced, will engage the interior spaces walls and power systems. The magnetic charge will memory shape the walls into work mode, as well as be able to power appliances and electronics, charge cell phones and ipods. The room can take on sleeping and waking/working states and its interior will reflect that.
2. Nanowire "Farm"
The nanowire "farm" will be a component "planted" on the windows and allowed to grow and collect solar radiation that will be used to power the buildings larger utilities.Now that the two main smart materials components of the building project have been identified, let us get to the more technical aspects of what these components are and how they function.
Magnetic Shape Memory Alloys
Magnetic shape memory (MSM) alloys have the capability to produce large magnetic field-induced strain of several percent. The large strain can either be caused by a magnetic field-induced structural reorientation (usually by twin boundary motion) or by a magnetic field-induced phase transformation (usually a martensitic phase transformation). The former is mostly referred to as MSM-effect, magnetoplasticity or more precisely as magnetically induced reorientation (MIR). The magnetic field-induced phase transformation is correctly referred to as MSM effect or as magnetically induced martensite/austenite (MIM/MIA). During MIR, twin boundaries move in order to allow those twin variants having a smaller angle between easy magnetization axis and applied field direction to grow, at the expense of unfavourably oriented twin variants.
Structural reorientation gives rise to strain (a), which usually occurs by twin boundary motion, either by an external stress or magnetic field (b).
The most investigated MSM-material so far is the Heusler alloy Ni2MnGa, but also other MSM-alloys and MSM-polymer-composites have been under scrutiny in order to overcome some of the disadvantages of (bulk) Ni2MnGa, e.g. brittleness, difficult preparation and cost. The magnetic field and the stress induced movement of twin boundaries can be exploited for actuators, sensors and, as it is an energy dissipating process, also for vibration damping devices. Our group is working mainly on different, bulk MSM-alloys and MSM-polymer-composites.
Ni-Mn-Ga
Ni-Mn-In-Co
Ni-Fe-Ga-Co
MSM-polymer-composites
Ni-Mn-Ga
The effect of magnetic field induced twin boundary motion was first discovered in 1996 on a Ni-Mn-Ga single crystal. Figure A shows an orientation map (~1x1mm² area) of such a single crystal, imaged by the electron back-scatter diffraction method (EBSD). The structural domains (twin variants) with different crystallographic orientation (represented by different colors) are separated by straight and, most importantly, mobile twin boundaries (thin black lines). Magnetic field-induced twin boundary motion generates typical jumps in magnetic field dependent magnetisation measurements. Such jumps are shown in figure B for a polycrystalline fibre. The fibre consist of several grains along the fibre axis (figure C). Magnetic field-induced twin boundary motion was proven in the polycrystalline fibre by EBSD (figure D, URL).
Ni-Mn-Ga: EBSD orientation map of a single crystal (A). Magnetisation vs. magnetic field curves (B) of a polycrystalline fibre. SEM image and EBSD orientation map of a polycrystalline fibre (C). Proof of magnetic field-induced twin boundary motion in polycrystalline fibre by EBSD (D).
Take MR fluids, for instance. Under normal conditions, magneto-rheological fluids are free-flowing with a viscosity akin to motor oil. In the presence of a magnetic field, the fluid can become a near-solid in milliseconds. It can return instantly to its fluid state when the magnetic field is withdrawn.Jacob Rabinow invented MR fluid while he was at the National Bureau of Standards in the 1940s. An early picture of a demonstration of the material's capabilities showed an MR fluid device supporting a 117-pound woman suspended on a swing. For decades, until the technical infrastructure grew up around it, MR fluid did not get past the point of novelty.