Machining of NiTi based shape memory alloys

The machinability of NiTi based shape memory alloys has been examined. Starting with turning experiments, cutting parameters were varied within a wide range. In addition, the influence of the cooling lubricant concept was investigated. After reaching acceptable results for turning, the field of investigation was extended to the drilling process. Furthermore, first examinations regarding deep hole drilling of tubes from NiTi shape memory alloy were carried out. The machining process was optimised with respect to environmental and commercial aspects with minimal influence on the characteristics of the shape memory alloys. The machining process was evaluated in terms of tool wear, cutting forces and machining quality. The tool wear was analysed with a scanning electron microscope and the influence of the machining on the subsurface zone was investigated by micro hardness measurements.