What can directed energy deposition (DED) systems use to prevent metal powders from oxidizing?

Directed energy deposition (DED) systems typically utilize inert shielding gas to prevent metal powders from oxidizing. When metal powders are exposed to air, they can react with oxygen, leading to oxidation, which compromises the integrity and performance of the material. Inert gases, such as argon or nitrogen, are used in the DED process to create a protective environment around the deposition area. These gases do not react with the metal powders and thus effectively inhibit oxidation during the deposition process.

Using inert shielding gas is critical in preserving the quality of the metal being deposited, ensuring better mechanical properties and a consistent microstructure in the final product. High temperature vacuum can also prevent oxidation but is generally more costly and not practical for all DED applications. Natural atmosphere and water vapor, on the other hand, would increase the likelihood of oxidation rather than prevent it, making them unsuitable for DED processes focused on maintaining the integrity of metal powders.