The aim of the DFG Research Unit 5250 is the development and validation of an integrated solution for the manufacturing, characterization, and simulation-based design of additively manufactured implants in maxillofacial surgery, taking into account physiological conditions of the individual bone situation. Within the project, the microscopic and mechanical deformation and damage behavior under cyclic loading as well as corrosive exposure of additively manufactured (AM) Ti-6Al-4V lattice structures is investigated. The aim is to establish an extensive understanding of the mechanical and corrosive properties for the simplified 2D geometry which will then be transferred to 3D lattice structures.
In the investigations, as-built AM bulk Ti-6Al-4V material was first characterized. Novel approaches were implemented to detect the process-induced surface roughness, as well as the effective bearing cross-section, by micro-computed tomography (µCT). As next, the damage mechanisms within a single unit cell plane (2D) were analyzed. To detect material reactions during fatigue loading, various measurement equipment consisting of digital image correlation (DIC), direct current potential drop system (DCPD) and infrared thermography (IRT) was adapted. Thereby, measurement quantities could be clearly correlated with material reactions. The findings were then transferred to 3D lattice structures consisting of several linked unit cells and the present damage progress was deeply analyzed. Examples are presented to reveal the potential to enhance the reliability of AM lattice structures and component design based on comprehensive defect-microstructure-property relationships to be integrated into robust modeling approaches.