Biocompatibility of Voronoi porous structure by selective laser melting

Biocompatibility has been a major concern in the field of medical implants, and the “stress shielding” effect can be detrimental to the growth of bone cells. In this work, a parametric irregular porous structure model based on bionics design was established. The influence of different parameters on the elastic modulus, compressive strength, average pore size, and porosity was investigated. An optimization model using the grey relational analysis was established by controlling the irregularity, seed points, and strut diameter. With the goal of meeting biological requirements, the optimization results showed that the elastic modulus decreased by 40.21% and the porosity increased by 17.58%. Irregularity had little effect on the elastic modulus, porosity, and average pore size, and it was negatively correlated with compressive strength. The strut diameter and seed points were positively correlated with the elastic modulus and compressive strength but negatively correlated with the porosity and average pore size, and the seed count had the largest impact. By adjusting these parametric models, the optimization factors were obtained based on the elastic modulus, porosity, average pore size, and compressive strength of human bone. These results provide theoretical guidance for studying the mechanical properties of irregular porous structures fabricated via selective laser melting.