The work presented focuses on ideas for improving ATZ ceramics for use as a material for implants in high-load applications, such as knee implants and hip implants for early intervention.
Up to date, Mathys’ ATZ ceramic ceramys® has very good mechanical and tribological properties with a biaxial bending strength up to 1000 MPa, a fracture toughness of 7,9 MPam^(1/2) and wear rates of 0,06 mm³/million cycle in the hip simulator under edge loading conditions. Ceramys® is currently only used for femoral heads and inserts for hip and shoulder arthroplasty. The general challenge with ceramics is their brittle fracture behavior, so that ceramics have so far played a subordinate role in highly stressed applications where complicated or thin-walled geometries are required. Regarding implants, this is the case in the area of the knee joint, as well as in the area of early bone-saving implant technology. Current ceramic implant materials are not yet sufficient in terms of strength and fracture toughness to solve this problem. Systems available on the market are very thick-walled and do not allow a bone-saving solution.
First promising results of a preliminary project for hip implants were continued with a series of experiments by varying the composition and preparation parameters. The results are to be presented. Furthermore, possibilities to modify the ceramic with respect to dopants in order to optimize the mechanical properties and to achieve a very high hydrothermal aging resistance will be discussed.
The results were obtained within the framework of the RUBIN alliance “SAPHIR high-performance ceramics” from the Tridelta Campus Hermsdorf (funded by BMBF, FKZ: 03RU1U161D).