Ferromagnetic shape memory alloys (MSMAs), such as Ni-Mn-Ga single crystals, can exhibit the shape memory effect due to an applied magnetic field at room temperature. Under a variable magnetic field and a constant bias stress loading, MSMAs have been used for actuation applications. Under variable stress and a constant bias field, MSMAs can be used in power harvesting or sensing devices, e.g. in structural health monitoring applications. This behavior is primarily a result of the approximately tetragonal unit cell whose magnetic easy axis is approximately aligned with the short axis of the unit cell within the Ni-Mn-Ga single crystals. Under an applied field, the magnetic easy axis tends to align with the external field. Similarly, under an applied compressive force, the short side of the unit cell tends to align with the direction of the force. This work introduced a new feature to the existing macro-scale magneto-mechanical model for Ni-Mn-Ga single crystal. This model includes the fact that the magnetic easy axis in the two variants is not exactly perpendicular as observed by D’silva
- NSF-PAR ID:
- 10394773
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Smart Materials and Structures
- Volume:
- 32
- Issue:
- 2
- ISSN:
- 0964-1726
- Page Range / eLocation ID:
- Article No. 025018
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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