Alloying AlSi10Mg and Cu powders in laser Single Scan Tracks, melt spinning, and Laser Powder Bed Fusion

The material palette available for Laser Powder Bed Fusion (LPBF) process is still limited. The mixing of different powders, here AlSi10Mg + Cu, and alloy synthesis by Single Scan Tracks (SSTs) and Melt Spinning (MS) were performed in this work for fast testing the new composition and reducing the building time and amount of powder employed. Then LPBF massive samples were manufactured to verify the outcome of the procedure. In all three cases an AlSi10Mg + Cu alloy was obtained, some residual inhomogeneity in Cu distribution being found in the SST sample. Microstructural features of the LPBF sample are intermediate with respect to SST and MS ones in terms of cell size of primary Al, while the eutectic morphology of Si is close to that of the ribbons. Nanoindentation tests showed an increase in hardness of the Cu-added samples with respect to that of the base AlSi10Mg alloy. XRD results indicated the occurrence of supersaturation of both Si and Cu in the as quenched samples and DSC analyses provided information on temperature and enthalpy of exothermal signals due to precipitation.