Magnetic Shape-Memory Foam With Large Magnetic-Field-Induced Deformation
- 技术优势
- Shape-memorySignificantlyhigher magnetoplastic strain Use of foamstructures to diminish internal crystal constraints to dislocationLess expensivethan leading nonmagnetoplastic magnetorestrictive materialsMagnetically induced strain about 50 times larger than reported for nonporous, fine-grained Ni-Mn-Ga materials.
- 详细技术说明
- Polycrystalline Ni-Mn-Ga foam magnetic shape-memory alloys exhibiting significant reversible magnetic field-induced strain.#materials #manufacturing #MEMS #actuator
- *Abstract
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Northwestern researchers have developed a polycrystalline Ni-Mn-Ga foammagnetic shape-memory alloy exhibiting magnetically induced strain about 50times larger than reported for nonporous, fine-grained Ni-Mn-Ga materials. While magnetic shape-memory alloys enablerapid, large-strain actuation upon the application of a magnetic field, thereare a number of limitations to large magnetoplastic strains. The growth of Ni-Mn0Ga single crystals isslow and leads to several segregation which affects local composition, crystalstructure and magnetoplastic strain. This invention overcomes these constraints by creating foam structureswith pores that significantly reduce internal crystal constraints todislocation, in the presence of a magnetic field. The foam structures are comparable in strainand response time to leading nonmagnetoplastic magnetorestrictive materialssuch as Terfenol D, which requires a bias stress for full strain potential, andcontains the more expensive Tb and Dy metals.
- *Inventors
- Yuttanant BoonyongmaneeratDavid Dunand*Peter MullnerMarkus Chmielus
- 国家/地区
- 美国
