Experimental and numerical investigations for mechanical and microstructural characterization of micro-manufactured AZ91D magnesium alloy disks for biomedical applications

In this study, the microstructure, mechanical and biological properties of the Mg-based implant samples prepared by the combination of micro-manufacturing and powder metallurgy route were investigated. Porous AZ91D Mg alloy disks with smooth and textured surfaces were manufactured under compaction pressures of 25 and 40 MPa at 150 °C and under sintering conditions of 380 °C for 30 and 150 min. The phase changes and microstructure were analyzed using X-ray diffraction (XRD), scanning electron (SEM) and light microcopy. The mechanical properties were characterized using diametral tensile and hardness tests. The relative densities were also calculated by their weights and volumes. As compaction pressure increased, relative densities of the disks increased (0.57-0.67%) as well as the diametral tensile strength (2.55-3.01 MPa) and Vickers micro-hardness values (13.5-84.1 HV2). The validity of relative density measurements was provided by image processing technique and finite element method. It was observed that cells adhered and proliferated more on disks with textured surface of channels than on disks with a smooth surface. Cell culture studies showed that Mg alloy disks were cytocompatible.