Simulation of the production of Inconel 718 and Ti6Al4V biomedical parts with different relative densities by selective laser melting (SLM) method

Abstract

Inconel 718 and Ti6Al4V which are the most widely used alloys in metal additive manufacturing, are preferred in applications in many fields such as automotive, aerospace and biomedical. As it is known, functional lightweight parts attract the attention of researchers due to their high specific strength despite their light weight. As a result of the increasing interest, the idea of producing lightweight parts with superior properties such as homogeneous distribution of the load and good absorption with additive manufacturing (AM) technology has come to the fore. Although AM methods such as selective laser melting (SLE) have many advantages over traditional manufacturing methods, residual stresses and distortions occur in the part during production, and their measurements in cellular structures are experimentally very difficult and time consuming. In this study, cellular structures used as scaffold and implant core structure in the biomedical field were designed with 100%, 73.4% and 42.6% infill rates. The residual stresses (sigma(x), sigma(y), and sigma(z)), distortions, plastic strains and maximum temperature values that occur during the production of these cellular structures from Inconel 718 and Ti6Al4V materials by SLM method were determined by the Amphyon 2021 AM simulation program. According to the obtained results, plastic strains, which provide a prediction of crack formation, were localized in the corner regions between the support structure and the main part. In addition, after a critical manufacturing height, higher maximum temperature values were observed in the cellular structures than the full structure.