Applications of industrial computed tomography in the manufacturing process of medical implants made from nitinol

Industrial computed tomography (CT) enables the non-destructive three-dimensional representation and measurement of workpieces. Applying CT technology, internal structures or shape deviations can be measured and material defects can be detected. For this purpose, the emitted X-rays are directed through the workpiece to be examined and detected by a detector on the opposite side. The workpiece rotates and projection images from different angles are recorded. Both, magnification and field of view are mainly determined by the distance between the workpiece and the X-ray source. Subsequently, a three-dimensional volume image is calculated from the radiographs and the object is digitally reconstructed.

CT technology offers interesting opportunities to complement conventional measurement technology in the production of medical implants made from nitinol. In addition to the dimensional inspection at the end of the manufacturing process, opportunities and applications are opened in process and product development. ADMEDES has already successfully adapted CT technology in prototype construction and process development and benefits from accelerated development cycles and increased process expertise. Shape measurements enable the full comparison of the workpiece with the customer specification and optimization of the heat treatment tools for shape setting. CT measurements are also applied for gaining insight into mass removal processes to optimize process parameters e.g. to achieve a consistent wall thickness. In this work, applications of CT technology in the manufacturing process of medical implants made from Nitinol are presented and challenges regarding the use in a production environment are discussed.