Shape Memory Alloy Art (SMA-Art) Shapes

  • Magazine Article
  • TBMG-28562
Published March 01, 2018 by Tech Briefs Media Group in United States
Language:
  • English

Shape memory alloys (SMAs) have the unique ability to recover large deformations in response to thermal, mechanical, and/or magnetic stimuli. This behavior occurs by virtue of a crystallo-graphically reversible martensitic phase transformation between a high-symmetry parent austenite phase and a low-symmetry martensite phase. In general, when the material is deformed in the martensitic condition, the induced deformation can be recovered by applying a stimulus above certain magnitude (e.g., temperature, load, magnetic field), but as long as the critical transition point is not reached, it will retain the deformed condition indefinitely until actuated (e.g., heated). The innovation described herein utilizes the concept of shape setting a desired form that can be deformed and recovered upon the application of a stimulus. In this context, shape setting refers to the method of forming a SMA shape consisting of deforming the material into a form, constraining the material in all dimensions, heating to a certain temperature, holding isothermally for some period of time, and then cooling back to room temperature under the same dimensional constraint.