Geometric Characteristics of Scaffolds Made by Additive Manufacturing

Additive manufacturing (AM) allows producing objects with functional internal structures; one of their applications is the production of medical implants (scaffolds), which may substitute bone tissue. The aim of this study is to evaluate, by micro computed tomography (mu CT), the geometric accuracy of scaffolds manufactured from Ti-6Al-7Nb alloy by selective laser melting (SLM). Micro-CT is a non-destructive method for investigating internal object structures. Its application in analysis of bone scaffolds allowed obtaining full geometric characterization of manufactured structures as 3D models and evaluation of the conformance of the scaffolds to their CAD designs. The influence of building direction during production of the quality SLM structures was also examined. Scaffold characteristics important for the application in tissue engineering, such as porosity and the actual surface area, were obtained. Validation of the mu CT method, by examining selected cross-sections with a scanning electron microscope (SEM), proved that differences in dimensional characteristics of structures did not exceed 10 micrometers.