Finite element analysis of machining damage in manufacturing ceramic implants
Ceramics are popular biomaterials used to manufacture orthopedic implants due to their excellent biomechanical properties. The inherent high hardness and brittleness of ceramics make precision machining of implants very difficult to achieve complex geometry and required surface integrity. Currently, grinding with diamond wheels is the most widely used process to machine ceramics. However, the process mechanics and damage mechanism in ceramic machining are not well understood. This work presents an introduction to ceramic implants, a comprehensive assessment on manufacturing of ceramic implants, and a comparison of temperature-dependent mechanical behavior models of Al2O3. Ceramic grinding is often used to machine orthopedic implants, yet a deep understanding of the alumina mechanical behavior, in particular machining damage, is not well established. To have an insight into the process mechanism, a 3D finite element model has been developed for single-grit ceramic grinding using the Johnson–Holmquist constitutive model to predict machined groove topography, subsurface damage, and cutting forces. In addition, the model predictions are correlated with the observed experimental phenomena.