Flex bending fatigue testing of wires, foils, and ribbons

Medical devices, such as guide wires, valves, needles, and stents are often subjected to cyclic loading conditions in service, while there is also an increasing demand for smaller devices made with materials that are difficult to machine. Fatigue testing of such structures is complicated by their small dimensions, particularly under fully reversed loading conditions. This paper summarizes our recent work on a variety of different materials (e.g. 316LVM, Cu-15Ni-8Sn, Nitinol, amorphous metals) where flex bending fatigue has been utilized to develop fatigue-life curves of as-received materials (e.g. wire, foil, sheet) under fully reversed conditions.