The deliverable work typical of the nickel-titanium SMA is one joule per gram per cycle. By contrast, an electrostatic actuator of the same volume might generate 10 -3 microjoule, and a comparable piezoelectric device is limited to approximately 0.1 microjoule per cycle. Because of the phase transformation the actuation takes place in a small temperature range. Heating by electric current can take much less than one millisecond. The use of thin film SMA's as microactuators can improve the performance of micromechanical devices by several orders of magnitude.
Heat treatment can significantly modify the mechanical characteristics.
The present method of making microactuators is by vacuum sputtering. Parameters for sputter deposition need refinement. Alternative methods of deposition should be investigated. For automotive use, in which ambient temperatures may exceed this range, available alloys are not suitable. The transition temperature of titanium-nickel alloys can be raised by substitution of Au, Pt, Pd for Ni or Zr and Hf for Ti.