Assessment of Moisture Content and Its Influence on Laser Beam Melting Feedstock

Additive Manufacturing (AM) techniques are known for building functional parts by adding layers of material. This layer-wise fabrication of metal parts yields freedom of design, weight reduction and product customization. Most of the metal AM processes use powder as feedstock, as small particles give freedom to the process to create all kind of complex structures with high tolerances. However, their (relatively) large surface can be affected by environmental conditions, such as moisture and elevated temperature, and by contamination. In the present research, Laser Beam Melting (LBM) powders are investigated to determine and quantify (i) the typical moisture content in an as-received batch, (ii) how to prevent this kind of contamination by proposing pre-treatments for the powders and (iii) its impact on the LBM process and products. In general, avoiding contamination during the production leads to a better quality and prolongs the product lifetime.