Processability of Aluminium Composite Alloys by Laser Powder Bed Fusion

Additive manufacturing (AM) techniques are garnering a lot of attention across many industrial fields thanks to several advantages. Among them, the ability to produce complex shaped components with a great freedom of design can lead to the creation of light weight parts, which is particularly crucial for the industrial development of AM techniques. The use of laser powder bed fusion (LPBF) technology, which involves the melting of selected powder bed regions with a laser beam to create metallic components using a layer-by-layer strategy, has gained attention in recent years. The part quality of the LPBF products can be controlled trough the building parameters. Aluminium is the second most globally used structural material after steel; it shows low density, high corrosion resistance, and excellent combination of physical and mechanical properties. However, despite this material has a wide application range, it is hardly processable by L-PBF because of a severe solidification cracking. This thesis is focused on 2618 aluminium alloy, which was developed to raise the temperature limit of conventional 2000 series. Today, aerospace industries are working to create lightweight materials with higher specific strength. The lack of in-depth studies on this specific alloy in AM increases the need to investigate its characteristics. The first stage in defining an LPBF process for new alloys or systems is parameter optimization. In this study, single scan track (SST) approach is used for the preliminary parameter screening. Test samples were printed by LPBF process with the aim of finding ranges of laser power and scan speed values for massive production. The processability of five different powder configurations including pure 2618 alloy and the latter reinforced with TiB2 particles using different strategies was investigated. Both visual and geometrical aspects of each track were studied using on-top and cross section analyses.