Investigating how water temperature affects the rotational dynamics of a nitinol engine

Nitinol is an alloy of nickel and titanium. It is a shape memory alloy that is malleable when cooled, but returns to its original shape when heated. Nitinol undergoes phase transformation between martensite and austenite. The transformation of phases creates motion. The aim of this experiment is to investigate how changing the temperature of the water heating the wire affects the rotational dynamics of a pulley system with a Nitinol wire. We analysed video recordings of the rotation at different temperatures. Higher water temperatures resulted in higher rotational speeds (RPM) of the wheel.