Instruments and methods for measuring a property of a shape memory alloy
are provided. The instrument includes a base plate, a non-contact movable mass,
a force gauge, an actuator, a biasing spring, a heater for heating the shape memory
alloy, and a non-contact displacement detector. The biasing spring and the shape
memory alloy are disposed whereby a force applied thereby is applied substantially
through a center of stiffness of the movable mass. The displacement detector measures
a displacement of the movable mass in a colinear direction with a direction of
movement of the movable mass and with a direction of the force applied by the biasing
spring and the shape memory alloy. The linear motion stage comprises a housing
and at least one guide bar, and wherein a calculated axial expansion of the guide
bar is substantially equal to a calculated axial expansion of the base plate.
