Investigation of mechanical performance of hybrid design porous structures manufactured from CoCr Alloy

Depending on the developing metal additive manufacturing technology, it has become possible to produce porous structures by creating different designs that are difficult to produce with traditional production methods. Thus, by creating different designs, individual, lightweight and highly biocompatible, porous implants that are suitable for the structure of human bones and allow cell migration can be produced. Since the mechanical responses of porous structures result from the effects of the many independent buttresses that form the cell size and the cell geometry, there is great potential in examining the mechanical behavior of these structures. When the studies in the literature are examined, there are many studies on uniform lattice structures, but hybrid structures have become very popular recently. Thanks to these designs, structures that are designed as hybrids can show higher mechanical strength than non-hybrid types. In this article, double and triple hybrid Cobalt Chromium alloy (CoCr) designed with reference to human bone structure and Cobalt Chromium alloy (CoCr) lattice structures were produced by SLM method. Double and triple hybrid lattice types showing plastic deformation under the applied force were investigated. The effect of missing buttresses due to manufacturing defect on the lattice properties and how the deformation is distributed throughout the lattice were investigated. The porosity ratios, cell model, cell density, shape geometry and printing results of the porous structures were compared. As a result of the mechanical test, hybrid structures showed different mechanical properties from each other because different porosity ratios and unit cells were used in the scaffold structures. In double hybrid scaffold models, the maximum stress belongs to the BDWN + TOL model and is measured as 518.20 MPa, while in triple hybrid scaffold models, the maximum stress belongs to the OT + BDWN + TOL model and is measured as 475.25 MPa.