Selective Laser Melted Porous Ti-6Al-4 V Scaffolds: Modelling, Manufacturing, and Effect of Microstructure on Mechanical Properties

Abstract

Ti-6Al-4 V alloy is widely used in medical implants, particularly in orthopedics application. Additive manufacturing (AM), specifically selective laser melting (SLM) is useful for porous scaffolds fabrication where complex passages facilitaes bone re-growth. This study focused on the modeling, manufacture, and testing of microstructure and mechanical characteristics of seven different scaffolds (Diamond, Cross, Grid, Vinties, Tesseract, Star, and Octet) of 15 mm cube with 65% porosity. Average pore area and strut thickness of scaffolds are measured using Stereo microscope. All these fabricated scaffolds are experimentally tested under compressive loads in INSTRON testing machine. The compressive test results are also compared with the numerical simulation results generated using finite element analysis (ANSYS) software. Maximum load cell capacity of ± 25 kNis used during compression testing in INSTRON. The Grid type scaffold shows maximum ultimate compressive strength of 101.39 MPa and an effective elastic moduli of 10.33 GPa with an average pore area of 2,417,618.517 µm² and strut thickness of 740.249 µm. This variant of the scaffold will be more compatible with the human bone’s elasticity, and it can also mitigate stress-shielding effects during healing.