Cold Spray Deposition of Aluminium 6061 Decorated with Al2O3 Nanoparticles

Cold Spray Deposition of Aluminium 6061 Decorated with Al₂O₃ Nanoparticles

Among all structural alloys, only limited metal powders are customized for printing techniques such as cold spray. The in-situ alloying can serve as a feasible alternative to developing new materials for printing. We have decorated AA6061 powders with Al₂O₃ nanoparticles as an alternative method for mixing the powders. The AA6061-Al₂O₃ composite was selected as the model material for this study. The SEM microscopy of decorated powder revealed the successful production of composite material. The Flowability of two powders was examined, which demonstrates the decoration process did not dramatically affect the composite powder rheology. Both primary Al6061 and decorated powders were deposited on an AA6061 substrate with a low-pressure cold spray system. The deposition efficiency, bonding mechanism between coatings and the substrate, coating quality and defects, surface roughness, and hardness of deposited materials for composite AA6061-Al₂O₃ and AA6061 coatings were compared. Finally, the microstructural change in the coating after precipitation hardening heat treatment was studied. Results show the proposed decoration has significant benefits.