Hyperelastic shape setting devices and fabrication methods

1. A dental archwire comprising a hyperelastic, single-crystal shape memory CuAlX alloy, where X is Ni, Mn, Nb, or Be, the dental archwire having a shape-set curved length, two ends that define a longitudinal axis along an arch extending approximately 180 degrees, and either a round diameter of between about 0.013 to about 0.026 inches or a rectangular cross-section with dimensions of between about 0.016 by 0.016 inches and about 0.020 by 0.030 inches, wherein one major axis of the single-crystal is parallel to the longitudinal axis from one end to the other end.

2. The dental archwire of claim 1 , formed by the method of:

heating a wire of single-crystal shape memory CuAlX alloy to a first temperature sufficient for annealing the alloy;

forcing the wire into a dental arch shape while the wire is held at the first temperature, wherein the heating and forcing steps are performed in less than 10 seconds; and

rapidly cooling the alloy to room temperature sufficiently quickly to cause the alloy to remain a single-crystal in the dental arch shape.

3. The dental archwire of claim 1 , formed by the method of:

heating a wire of single-crystal shape memory CuAlX alloy to an annealing temperature sufficient for annealing the alloy;

forcing the heated wire into a dental arch shape by forcing the wire against a mandrel, wherein the steps of heating and forcing the wire against the mandrel are performed in less than 10 seconds; and

rapidly cooling the wire by quenching to a cooling temperature sufficiently quickly to cause the alloy to remain a single-crystal in the dental arch shape.

4. The dental archwire of claim 1 , wherein the arch traverses an arc extending approximately 180 degrees in an unstressed state.

5. The dental archwire of claim 1 , wherein the single-crystal shape memory CuAlX alloy is CuAlNi.

6. The dental archwire of claim 5 , formed by the method of:

heating a wire of CuAlNi alloy to a first temperature sufficient to place the Cu, Al and Ni in solution;

rapidly quenching the alloy to a second temperature to prevent precipitation of the Cu, Al and Ni so that the alloy remains as a single-crystal of CuAlNi;

constraining the alloy into a dental arch shape;

heating the alloy to a third temperature for a first time period, wherein the third temperature and first time period are sufficient to cause the alloy to lose its strength; and

cooling the alloy to a fourth temperature for a second time period, wherein the fourth temperature and second time period are sufficient to cause the alloy to remain a single-crystal in the dental arch shape.

7. The dental archwire of claim 1 , wherein the ends of the dental archwire are in the martensitic phase at body temperature.

8. A dental archwire comprising a hyperelastic shape memory CuAlX alloy of a single-crystal where X is Ni, Mn, Nb, or Be, the single-crystal being defined by a unit cell having an a-axis, a b-axis, and a c-axis,

wherein the dental archwire has two ends that define a longitudinal axis extending approximately 180 degrees in which one of the a-axis, the b-axis, and the c-axis of the single-crystal is parallel to the longitudinal axis along a length of the arch from one end to the other end.

9. The dental archwire of claim 8 , wherein the single-crystal is in an unstressed state.