Study of the superabrasive machining performance on additive manufactured AlSi10Mg alloy with cBN wheels
摘要
Among Additive Manufacturing (AM) processes, Laser Powder Bed Fusion (PBF-LB) is a well-established technology for the fabrication of advanced engineering components. In particular, components intended for heat transfer applications are typically manufactured from aluminium alloys due to their high thermal conductivity, and are designed with complex geometries to increase the available surface area for heat dissipation. However, the finishing of components manufactured by PBF-LB is far from being a resolved research field, especially when it comes to materials like aluminium alloys due to its strong tendency to adhesion during machining, making those challenging materials to machine. Superabrasive machining (SAM) is presented as a postprocessing solution for finishing AM-ed components because it combines the advantages of using superabrasive grinding tools with milling advances regarding. Moreover, SAM process employs small tools capable of contouring complex shapes as those obtained by PBF-LB process. In this work, the performance of cBN under SAM conditions on AlSi10Mg alloy AM-ed parts is analysed. To reach this goal, the wheel wear mechanisms and power consumption during AlSi10Mg alloy machining were studied. SEM-EDS analyses identified adhesion as the dominant wear mechanism, with aluminium content reaching 32.5 wt% under transient conditions and decreasing to 13.7–19.7 wt% in stable grinding. The force ratio (Fn/Ft) remained stable between 1.5 and 3, confirming an efficient cutting regime with dominant tangential forces and consistent material removal. Combined with the thin and detachable aluminium adhesion layers observed on the wheel surface, these results indicate a self-cleaning effect that maintains cutting efficiency and improves surface integrity (Ra < 5 μm) in the SAM of PBF-LB AlSi10Mg alloys.