Directed Energy Deposition of 316L Steel: Effect of Type of Powders and Gas Related Parameters

Directed Energy Deposition is an additive manufacturing technique for manufacturing or repairing of metallic parts. A number of studies have recently demonstrated that the part quality depends on various process parameters. However, the roles of gas related parameters and type of powder are still not well understood. In the present study, the influence of carrier gas flow rate, shielding gas and type of powder on the porosity and oxide contents of the as-deposited 316L steel, produced with the optimum process parameters, is investigated. The results show that, in order to obtain a rather fully dense component, optimum carrier gas flow rate and proper shielding gas together with as-received powder should be used. Furthermore, the research outcomes indicate that the presence of shielding gas and the type of used powder are an important key point to be considered in minimizing oxides in as-deposited parts.