COLLAPSIBLE, SHAPE MEMORY ALLOY STRUCTURES AND METHODS FOR FORMING SAME

摘要

A shape memory alloy structure may include at least two layers formed of shape memory material. Each layer is formed with a plurality of panels having side edges, wherein at least some of the adjacent layers are coupled together via a filler material such as a niobium metal, at selected edges of adjacent panels. The structure is moveable between a contracted position and an extended position and wherein the coupled edges form hinges for moving the structure between the contracted position and the extended position. The layers may form at least two substantially concentric tubular members with each tubular member may be formed of a plurality of scalloped panels separated by peaks forming the edges. The structure can effectively form a variety of medical devices such as, for example, a Nitinol based prosthetic cardiovascular stent, bone anchor, or cardiovascular valve. Methods for forming and fixtures for collapsing same are disclosed.