TY - PAT
T1 - Polycrystalline Foams Exhibiting Giant Magnetic-Field-Induced Deformation and Methods of Making and Using Same
AU - Dunand, David
N1 - filingdate: 2010-7-20
issueddate: 2013-11-19
Status: published
attorneydocketnumber: 2009-109-02
PY - 2011/3/17
Y1 - 2011/3/17
N2 - Magnetic Shape-Memory Foams for Actuators and Other Industrial Purposes
NU 2009-109
Inventors
Xuexi Zhang
David C. Dunand*
Peter Mullner
Markus Chmielus
Cassie Witherspoon
Short Description
Polycrystal memory foam for less expensive, more stable actuators
Abstract
Magnetic shape memory alloys (MSMAs) are a field of active materials that enable fast, large-strain actuators. Single crystal shape-memory alloys have thus far been utilized; very high (~10%) magnetic-field-induced strains (MFIS) for single-crystal nickel-manganese-gallium (Ni-Mn-Ga) alloys have been measured. However, Ni-Mn-Ga single crystals are brittle and difficult to prepare, thus limiting their commercial potential. Randomly textured, fine-grained, polycrystalline Ni-Mn-Ga alloys are easier to manufacture, but result in near-zero MFIS. Northwestern inventors have overcome these performance limitations by synthesizing the alloy as a polycrystalline foam structure. The foam permits single crystallinity deformation to extend over longer distances, resulting in greater field induced strain (2-4%) - i.e., the foam changes shape in strong magnetic field. This development will allow for the manufacture of actuators using polycrystals, which are less restrictive to produce than the single-crystal variety.
Applications
o Long-stroke actuators (aerospace, automotive, and
biomedical devices)
o Sensors
o Magnetic cooling systems
o Energy devices
Advantages
o Inexpensive casting process
o Actuation stroke 100 times that of piezoelectric actuator materials, but with comparable response time
o Compact, lightweight, and robust
IP Status
Issued US Patent No. 8,586,194
Marketing Contact
Allan Nader, PhD
Invention Manager
(e) [email protected]
(p) 847.491.4456
AB - Magnetic Shape-Memory Foams for Actuators and Other Industrial Purposes
NU 2009-109
Inventors
Xuexi Zhang
David C. Dunand*
Peter Mullner
Markus Chmielus
Cassie Witherspoon
Short Description
Polycrystal memory foam for less expensive, more stable actuators
Abstract
Magnetic shape memory alloys (MSMAs) are a field of active materials that enable fast, large-strain actuators. Single crystal shape-memory alloys have thus far been utilized; very high (~10%) magnetic-field-induced strains (MFIS) for single-crystal nickel-manganese-gallium (Ni-Mn-Ga) alloys have been measured. However, Ni-Mn-Ga single crystals are brittle and difficult to prepare, thus limiting their commercial potential. Randomly textured, fine-grained, polycrystalline Ni-Mn-Ga alloys are easier to manufacture, but result in near-zero MFIS. Northwestern inventors have overcome these performance limitations by synthesizing the alloy as a polycrystalline foam structure. The foam permits single crystallinity deformation to extend over longer distances, resulting in greater field induced strain (2-4%) - i.e., the foam changes shape in strong magnetic field. This development will allow for the manufacture of actuators using polycrystals, which are less restrictive to produce than the single-crystal variety.
Applications
o Long-stroke actuators (aerospace, automotive, and
biomedical devices)
o Sensors
o Magnetic cooling systems
o Energy devices
Advantages
o Inexpensive casting process
o Actuation stroke 100 times that of piezoelectric actuator materials, but with comparable response time
o Compact, lightweight, and robust
IP Status
Issued US Patent No. 8,586,194
Marketing Contact
Allan Nader, PhD
Invention Manager
(e) [email protected]
(p) 847.491.4456
M3 - Patent
M1 - 8586194
ER -