Effect of Process Gas and Powder Quality on Aluminum Alloys Processed by Laser Based Powder Bed Melting Process

The production of parts and components by Additive Layer Manufacturing (ALM) offers potential cost benefits for aeronautic applications. Laser Based Powder Bed Melting Process offers design flexibility while enabling weight reduction due to topological optimization by substitute conventional design and manufacturing routes. Especially aluminum alloys are highly sensitive to oxygen and hydrogen impurity during the process. Due to this, it is mandatory to control precisely and hold a low oxygen level while processing. Hereby it is possible to avoid any negative impact on the final mechanical properties as tensile strength and fatigue resistance. For the investigations, aluminum powder (Al-Si-Mg) is used. This paper will present the influence of the oxygen level during processing on the final mechanical properties of the part. Even if pure Argon is commonly used to inert the chamber, different sources of oxygen like powder, equipment and gas supply have a negative impact and will be investigated. [1]–[4]