Metal additive manufacturing by laser-powder bed fusion:Guidelines for process optimisation

Additive manufacturing is growing rapidly in the last decades due to the significant development in the laser technology and metal powder manufacturing. It offers a way to rapidly create near-net-shape engineered parts starting from a digital CAD file without the need for dies or molding. It also offers the ability to manufacture parts designed in a complex geometry and made of metals which are difficult to produce by using the traditional methods. One of the main obstacles in Laser-Powder Bed Fusion (L-PBF) for example is the dissimilarity in the produced parts' properties. The main reason behind this is the non-stationary nature due to the turbulence formation above the melt-pool area accompanied by weld fumes, metal evaporation, plasma and sparks formation. These effects increase within the individual printer as the fumes suspending and circulating with the inert gas increasing with the time. Also, these effects differ from one printer to another depending on the build chamber size and gas flow arrangement. This article is focused on exploring the (L-PBF) process in a step-by-step principle and present it to the researchers, technicians and even manufacturers especially those who have novice or lack of information about this technology. The study puts the main issues which must be considered and learned in a successful Additive Manufacturing (AM) lab to produce a functioning metal part.