Laser-based induction of the two-way memory effect into shape memory alloy components

Due to special material properties, among others their two-way memory effect (TWME), shape memory alloys (SMA) are finding increasing attention in micro system technology. However, only slow and quite complicated training methods are available to induce the TWME. At the Laser Zentrum Hannover e.V., investigations are being carried out to realize the induction of the TWME into SMA components using laser radiation. By precisely heating SMA components with laser radiation, local tensions remain near the component surface. Concerning the shape memory effect (SME), these tensions can be used to make the components execute complicated movements. Compared to conventional training methods to induce the TWME, this procedure is faster and easier. Further, higher numbers of thermal cycling are expected because of the low dislocation density in the main part of the component. Results regarding the dependence of the laser induced TWME on material and machining parameters will be presented.