Review of defects and their sources in as-built Ti6Al4V manufactured via powder bed fusion

Additive manufactured Ti6Al4V printed via powder bed fusion (laser or electron beam melting) is one of the most researched alloys for AM applications. However, even under optimized printer conditions, defects can still exist. This paper provides a brief review from industry literature on PBF printed Ti6Al4V microstructure, the powders used in the printing process, defects associated with the process, and unwanted microstructural conditions. The review is intended to provide general information and targets those new to the PBF process. Defects such as porosity, contamination, chemistry variances, balling, sputtering, cracks, lack of fusion, surface roughness, residual stresses, and their reported sources are discussed. Brief notes on defect influences on fatigue, and multi-laser related defects were provided for general awareness.