Abstract

Metal Additive Manufacturing (MAM) is a manufacturing technique that builds solid components layer by layer. In comparison to traditional manufacturing methods, metal additive manufacturing offers advantages by allowing the creation of intricate geometries while reducing the buy-to-fly ratio of components. Understanding how manufacturing parameters affect the mechanical properties of produced components is applicable to the research and development of materials used in aero-engine and biomedical applications.
The study that is the subject of this thesis examines the microstructure of Ti64 samples printed using Electron Beam Melting (EBM) with specific variations in process parameters, such as adjustments in beam current and scan speed intended to achieve varying microstructural properties. The study compares the variations in process parameters with the types of defects and overall sample porosity. Additionally, this research explores the relationship between process parameters, defect production, and the tensile and fatigue properties of the printed samples.
The results of the microstructure examination indicate that individual process parameters significantly influence print porosity for the same Volumetric Energy Density (VED). However, VED alone does not dictate alpha lath thickness or variations in tensile properties. While porosity and defect size do not notably affect tensile properties, they impact the fatigue life of the samples with larger defects leading to a shorter fatigue life. Optical microscopy analysis of print samples provides a local estimation of defect parameters for an initial assessment and prediction of global porosity in larger printed components.