Shape-Memory Wire Returns

Wire returns toward its trained shape. Ask students to predict what will happen. Bend wire cool, then warm it. Key idea: A reversible crystal-structure change makes the alloy remember a high-temperature form. Ask: How can metal 'remember' a shape? Safety and cleanup: Use warm—not boiling—water; ends rounded. https://instructional-resources.physics.uiowa.edu/4c4515-nitinol-wire