Which outcome is seen when a shape-memory alloy (SMA) wire, pre-strained at low temperature, is heated past its austenite transition temperature?

💡 Explanation

The SMA returns to its original shape due to a martensite-austenite phase transformation. Crystal structure shift triggers reverse shape change under load because the crystalline structure rearranges; therefore, shrinking is the answer, rather than yielding, maintaining coercivity, or resistance change.

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