Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003 · 18 citations · 0 references
Natural SciencesMaterials SciencePhysicsMagnetic MaterialsMaterials PhysicsMechanical Behavior Of MaterialsFerromagnetismMagnetic ActuationMagnetic Properties Of SolidsMagnetic Recording MaterialsMagnetism In SolidsShape Memory Alloy ActuatorsActuation StrainCompressionField-induced StrainMagnetic AlloysMagnetic Shape Memory AlloysRelative PhaseShape Memory Alloy Magnetic ActuatorsShape-memory Alloys
Magnetic-field-induced strain in single crystals of Ni-Mn-Ga magnetic shape memory alloys were studied under cyclic field conditions using a compression spring to reset the sample as H→0. Low frequency actuation strain of 2.5% degraded to about 1.5% at an actuation frequency of 500 Hz. Two resonant-like features appear in the ε(f) data, which appear to correspond to a broad test system resonance (100-200Hz) and a sample longitudinal resonance near 350 Hz. The relative phase of field and strain support the assignment of the 350 Hz resonance to the sample.