Alumina and YTZP ceramics have been established in joint arthroplasty since the 1970s and 1980s. Zirconia-rich dispersion ceramics of alumina and YTZP have also been known for decades for high strength, high fracture toughness and low wear rates. ATZ (alumina toughened zirconia) is used as joint implant by Mathys since 2007. New efforts were made to use ATZ for production of a surgical cutting tool.

This paper summarizes the initial investigations on standard ceramic manufacturing (CNC) compared to LCM (lithography-based ceramic manufacturing) of a ceramic cutting tool. The product development began with the formulation of clinical requirements and the design suitable for ceramic part and manufacturing process. After defining the requirements for the ATZ-ceramic based on standards (ISO 13356, ISO 6474-2), suited raw materials were defined and the slurry development for the LCM process was started. A debinding process and thermal treatment - sintering and HIP - were elaborated. High purity and elimination of any porosity are mandatory for clinical use. The whole process was accompanied by the determination of properties such as green density, microstructure, density after the thermal processes and geometry. Tests were carried out to create a cavity on artificial bone.

From appropriate raw materials meeting chemical requirements a suitable ATZ slurry was prepared. It was used to produce green parts. By adjusting debinding and thermal processes sinter densities of about 99,00 % theoretical density were reached. The microstructure could be adjusted that grain sizes for Al2O3 in the range between (0.39 - 0.41) µm and for YTZP in the range between (0.38 - 0.46) µm were produced. The cutting tool can create cavities in artificial bone up to 20 pcf density. Optimisation work is required for use in 30 pcf artificial bone.

First cutting tools made of ATZ ceramic were successfully realized with conventional CNC production and LCM.