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Showing 1 to 12 of 12 for “"Ferromagnetic Shape Memory Alloys"”.
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Orthopaedic applications of ferromagnetic shape memory alloys
Ferromagnetic shape memory alloys (FSMAs) are a new class of magnetic field-actuated active materials with no current commercial applications. By applying a magnetic field of around 0.4 T, they can exert a stress of approximately 1.5 MPa, exhibiting a strain of up to 6%. This thesis evaluates their …
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Acoustic assisted actuation of Ni-Mn-Ga ferromagnetic shape memory alloys
Ferromagnetic shape memory alloys (FSMA) have been shown in recent work to exhibit large magnetic field induced strains. The material generally requires a large threshold field (of order 3-4 kOe) to initiate the strain. Thus, the power requirements are large and actuators based on these materials …
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Dynamic actuation properties of Ni-Mn-Ga ferromagnetic shape memory alloys
… bandwidth of least 500 Hz in Ni48.5Mn29.5Ga21 ferromagnetic shape memory alloys (FMSAs) is achieved. Hardware was designed and constructed to measure frequency bandwidth, magnetic-field-induced strain, stress and magnetization driven from an applied magnetic field. The bandwidth in this …
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Ab initio based Monte Carlo model of phase transformations in ferromagnetic shape memory alloys
… predicting the phase transformation behavior of ferromagnetic shape memory alloys (FSMAs). This framework is intended to aid in the discovery of new FSMAs and optimize desired properties of existing FSMAs for engineering applications such as solid state refrigeration. Predicting the phase …
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An analysis of ferromagnetic shape memory alloys produced by melt spinning, sputtering and pulsed laser deposition.
Ferromagnetic shape memory alloys (FSMA) have recently attracted much interest and research because of their large magnetic-field induced strain. Strains of up to 10% have been reported in single crystals of Ni2MnGa at room temperature. The mechanism of twin boundary motion is understood to be …
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An Investigation of the Structural and Magnetic Transitions in Ni-Fe-Ga Ferromagnetic Shape Memory Alloys
… and magnetic transformations in Ni-Fe-Ga ferromagnetic shape memory alloys are very sensitive to both alloy chemistry and thermal history. A series of Ni-Fe-Ga alloys near the prototype Heusler composition (X2YZ) were fabricated and homogenized at 1423 °K, and a Ni₅₃Fe₁₉Ga₂₈ alloy was …
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Systematic analysis of the crystal structure, chemical ordering, and microstructure of Ni-Mn-Ga ferromagnetic shape memory alloys
Ni-n-Ga based ferromagnetic shape-memory alloys (FSMAs) have shown great promise as an active material that yields a large output strain over a range of actuation frequencies. The maximum strain has been reported to be 6% in the tetragonal martensitic phase and up to 10% in the orthorhombic phase. …
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Pulse-field actuation of collinear magnetic single crystals
Ferromagnetic shape memory alloys (FSMAs) are a class of alloys that exhibits the shape memory effect, as in the alloy nickel-titanium, sometimes known as Nitinol. In FSMAs, though, the shape changes are not brought on just by changes in temperature or mechanical stresses, but can also be driven by …
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Design and characterization of acoustic pulse shape memory alloy actuators
Single crystal Ni-Mn-Ga ferromagnetic shape memory alloys (FSMAs) are active materials which produce strain when a magnetic field is applied. The large saturation strain (6%) of Ni-Mn-Ga, and material energy density comparable to piezoelectric ceramics make Ni- Mn-Ga an interesting active material. …
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Understanding and development of combined acoustic and magnetic actuation of Ni₂MnGa single crystals
Ni-Mn-Ga based ferromagnetic shape memory alloys (FSMAs) have emerged as a promising new class of active materials capable of producing a large (several %) magnetic-field-induced strain (MFIS). FSMAs still have several characteristic shortcomings that may limit their potential applications. A …
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Magneto-mechanical properties and applications of Ni-Mn-Ga ferromagnetic shape memory alloy
Ferromagnetic shape memory alloys (FSMA's) have shown large strains under magnetic field as magnetic variants in the rnartensite rearrange to accommodate the applied field. The theoretical maximum field-induced strain is 6.3% in Ni-Mn-Ga FSMA, and results of 6.1% are presented. These strain …
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Fabrication and characterization of Ni-Mn-Ga ferromagnetic shape-memory alloy composites
Ferromagnetic shape-memory alloys (FSMAs) are a recently-developed class of active materials which show large extensional strains when a magnetic field is applied. Shear strains of 6% have been observed at room temperature in martensitic Ni-Mn-Ga single crystals. The strain effect in Ni-Mn-Ga FSMAs …