Applications of Shape Memory Effects

Abstract
In this paper a series of new medical applications for specific behaviour of shape memory alloys is presented. Several properties are well known, like the superelasticity and the shape memory effect, but there are some other interesting features that are used very scarcely. Examples are given of the use of the extraordinary shapeability of the martensitic material, in some cases in combination with high tensile strength, which makes memory metal a very special engineering material. For applications of superelasticity a new alloy was found, that exhibiths improved stiffness and an upper plateau stress as high as 1000 MPa. Single crystals show perfect constant plateau stresses, which give a well defined force in medical tools. Examples are given of instruments and medical implants using memory metals for functions as distraction, adjustability for customization, measuring, steerability and locking/unlocking of devices.