Ferromagnetic Shape Memory Alloy
	Overview
	NiMnGa is a type of ferromagnetic shape memory alloys (FSMA) which generates large strains (on the order of several percent) in two distinct mechanisms: 1) phase transformation between low temperature (Martensite) phase to a cubic crystal structure in the high temperature (Austenite) phase. 2) Twin boundary motion due to either mechanical or magnetic loading. The second mechanism has been more heavily researched as strains greater than 10% have been measured at frequencies in the hundreds of hertz. This makes it a potential candidate for use in large stroke, high frequency actuation devices. However, cost and durability issues with the bulk, single crystal material has resulted in significant research towards composite and thin films forms in hopes of bolstering the commercial appeal of this fascinating alloy

	Current Research Projects
	Ferromagnetic Shape Memory Alloy (FSMA) Composites
	Eric Gans
	Research has shown that FSMA’s can be used as viable dampers and actuators due to their significant magnetostrictive effect (> 5%) and large energy absorption (tan delta ~ 1). However, the inherent properties of the material (i.e. brittleness) have made it difficult to apply it in its bulk form. Composite forms allow for the embedded FSMA material to provide the active component with the resin matrix providing the structural support to enhance durability and allow for cyclic actuation. Current research focuses on the manufacturing of various composites to understand the interaction between the active FSMA materials and the surrounding resin matrix. Types of composites fabricated and tested are: planar (2-2), fibrular (1-3), and particulate (0-3).

	Damping in Ni-Mn-Ga
	David Ruggles
	Damping in Ni-Mn-Ga, a Ferromagnetic Shape Memory Alloy, is studied in polycrystalline bulk and thin film form. A Dynamic Mechanical Analyzer is used for bulk testing by varying temperature, frequency, and loading to measure tan delta directly. Thin film fabrication has been complete for an accelerometer design used for response comparison between accelerometers made with and without a damping layer. Possible applications include a phased array antenna and a high frequency high vibration accelerometer.