Development Of A Quality Management Method For The Production Process Of Semi-Finished NiTi-SMA Materials

Shape memory alloys (SMA) are functional materials that can remember a previous defined shape by thermal activation and also show high elastic properties. These effects are based on a reversible, diffusionless transition between the low temperature phase (martensite) and the high temperature phase (austenite).

Despite worldwide research efforts, product solutions based on SMA are only established in few mass-industrial applications. The main reasons for this are the lack of standardization and the absence of applied quality management methods which leads to large variations in industrially manufactured semi-finished SMA-products.

NiTi-SMA reacts sensitively to even small variations in the production process parameters. The investigation of the wire drawing and annealing procedures of Nickel-Titanium (NiTi) SMA shall serve as a basis for the development of a quality management method. Through material tests like tensile tests or activation tests, impacts of parameter variations during the wire-drawing and annealing process shall be analyzed, evaluated and validated methodically. The results of this validation shall be used as a basis for monitoring and quality management methods for the production process to gain a high reproducibility of semi-finished NiTi-SMA materials.

First results of this project are presented within the full paper as well as future prospects regarding SMA applications and industrial standards.