Functionality of laser-sintered shape memory micro-actuators

NiTi shape memory alloys are considered to be difficult to machine. Dimensional accuracy can hardly be met especially in micro-machining. Being a non-contact tool and therefore independent from machining forces, the laser is a promising alternative for manufacturing NiTi micro-parts. This paper presents research results on powder bedbased laser sintering of fine NiTi powders. Structures with a minimum width of approximately 50 μm can be generated without losing the special shape memory properties. The structures “remember” the shape which was set in the laser process. We show that phase transformation temperature can be influenced by process parameters.